Science.gov

Sample records for stainless steel plate

  1. Plating on stainless steel alloys

    SciTech Connect

    Dini, J.W.; Johnson, H.R.

    1981-09-11

    Quantitative adhesion data are presented for a variety of electroplated stainless steel type alloys. Results show that excellent adhesion can be obtained by using a Wood's nickel strike or a sulfamate nickel strike prior to final plating. Specimens plated after Wood's nickel striking failed in the deposit rather than at the interface between the substrate and the coating. Flyer plate quantitative tests showed that use of anodic treatment in sulfuric acid prior to Wood's nickel striking even further improved adhesion. In contrast activation of stainless steels by immersion or cathodic treatment in hydrochloric acid resulted in very reduced bond strengths with failure always occurring at the interface between the coating and substrate.

  2. Nickel release from nickel-plated metals and stainless steels.

    PubMed

    Haudrechy, P; Foussereau, J; Mantout, B; Baroux, B

    1994-10-01

    Nickel release from nickel-plated metals often induces allergic contact dermatitis, but, for nickel-containing stainless steels, the effect is not well-known. In this paper, AISI 304, 316L, 303 and 430 type stainless steels, nickel and nickel-plated materials were investigated. 4 tests were performed: patch tests, leaching experiments, dimethylglyoxime (DMG) spot tests and electrochemical tests. Patch tests showed that 96% of the patients were intolerant to Ni-plated samples, and 14% to a high-sulfur stainless steel (303), while nickel-containing stainless steels with a low sulfur content elicited no reactions. Leaching experiments confirmed the patch tests: in acidic artificial sweat, Ni-plated samples released about 100 micrograms/cm2/week of nickel, while low-sulfur stainless steels released less than 0.03 microgram/cm2/week of nickel, and AISI 303 about 1.5 micrograms/cm2/week. Attention is drawn to the irrelevance of the DMG spot test, which reveals Ni present in the metal bulk but not its dissolution rate. Electrochemical experiments showed that 304 and 316 grades remain passive in the environments tested, while Ni-plated steels and AISI 303 can suffer significant cation dissolution. Thus, Ni-containing 304 and 316 steels should not induce contact dermatitis, while 303 should be avoided. A reliable nitric acid spot test is proposed to distinguish this grade from other stainless steels. PMID:7842681

  3. Electroless nickel plating on stainless steels and aluminum

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Procedures for applying an adherent electroless nickel plating on 303 SE, 304, and 17-7 PH stainless steels, and 7075 aluminum alloy was developed. When heat treated, the electroless nickel plating provides a hard surface coating on a high strength, corrosion resistant substrate.

  4. Surface modified stainless steels for PEM fuel cell bipolar plates

    DOEpatents

    Brady, Michael P [Oak Ridge, TN; Wang, Heli [Littleton, CO; Turner, John A [Littleton, CO

    2007-07-24

    A nitridation treated stainless steel article (such as a bipolar plate for a proton exchange membrane fuel cell) having lower interfacial contact electrical resistance and better corrosion resistance than an untreated stainless steel article is disclosed. The treated stainless steel article has a surface layer including nitrogen-modified chromium-base oxide and precipitates of chromium nitride formed during nitridation wherein oxygen is present in the surface layer at a greater concentration than nitrogen. The surface layer may further include precipitates of titanium nitride and/or aluminum oxide. The surface layer in the treated article is chemically heterogeneous surface rather than a uniform or semi-uniform surface layer exclusively rich in chromium, titanium or aluminum. The precipitates of titanium nitride and/or aluminum oxide are formed by the nitriding treatment wherein titanium and/or aluminum in the stainless steel are segregated to the surface layer in forms that exhibit a low contact resistance and good corrosion resistance.

  5. 76 FR 31588 - Stainless Steel Plate in Coils From Belgium: Rescission of Countervailing Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ... International Trade Administration Stainless Steel Plate in Coils From Belgium: Rescission of Countervailing... countervailing duty (``CVD'') order on stainless steel plate in coils from Belgium. See Antidumping or... FR 23236 (May 3, 2010). On May 28, 2010, we received a request for revocation of this order from...

  6. 75 FR 64709 - Stainless Steel Plate in Coils From Belgium: Notice of Rescission of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... International Trade Administration Stainless Steel Plate in Coils From Belgium: Notice of Rescission of... ``Opportunity to Request Administrative Review'' of the antidumping duty order on stainless steel plate in coils... Administrative Review, 75 FR 23236, (May 3, 2010). On June 1, 2009, in accordance with 19 CFR 351.213(b),...

  7. Evaluation of silver-coated stainless steel bipolar plates for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Huang, Ing-Bang

    In this study, computer-aided design and manufacturing (CAD/CAM) technology were applied to develop and produce stainless steel bipolar plates for DMFC (direct methanol fuel cell). Effect of surface modification on the cell performance of DMFC was investigated. Surface modifications of the stainless steel bipolar plates were made by the electroless plating method. A DMFC consisting of silver coated stainless steel as anode and uncoated stainless steel as cathode was assembled and evaluated. The methanol crossover rate (R c) of the proton exchange membrane (PEM) was decreased by about 52.8%, the efficiency (E f) of DMFC increased about 7.1% and amounts of methanol electro-oxidation at the cathode side (M co) were decreased by about 28.6%, as compared to uncoated anode polar plates. These measurements were determined by the transient current and mathematical analysis.

  8. 77 FR 73013 - Stainless Steel Plate in Coils From Belgium: Antidumping Duty Administrative Review, 2010-2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-07

    ... International Trade Administration Stainless Steel Plate in Coils From Belgium: Antidumping Duty Administrative... results of the antidumping duty order on stainless steel plate in coils (steel plate) from Belgium.\\1... Review, 77 FR 32517 (June 1, 2012) (Preliminary Results). Based on our analysis of the comments...

  9. Stainless Steel Bipolar Plates Deposited with Multilayer Films for PEMFC Applications

    NASA Astrophysics Data System (ADS)

    Cho, Hyun; Yun, Young-Hoon

    2013-08-01

    A chromium nitride (CrN, Cr2N)/chromium (Cr)/indium-tin-oxide (ITO) system and a gold (Au)/titanium (Ti) system were separately deposited using a sputtering method and an E-beam method, respectively, onto stainless steel 316 and 304 plates. The XRD patterns of the deposited stainless steel plates showed the crystalline phase of typical indium-tin oxide and of metallic phases, such as chromium, gold, and the metal substrate, as well as those of external chromium nitride films. The nitride films were composed of two metal nitride phases that consisted of CrN and Cr2N compounds. The surface morphologies of the modified stainless steel bipolar plates were observed using atomic force microscopy and FE-SEM. The chromium nitride (CrN, Cr2N)/chromium (Cr)/indium-tin-oxide (ITO) multilayer that was formed on the stainless steel plates had a surface microstructural morphology that consisted of fine columnar grains 10 nm in diameter and 60 nm in length. The external gold films that were formed on the stainless steel plates had a grain microstructure approximately 100 nm in diameter. The grain size of the external surface of the stainless steel plates with the gold (Au)/titanium (Ti) system increased with increasing gold film thickness. The electrical resistances and water contact angles of the stainless steel bipolar plates that were covered with the multilayer films were examined as a function of the thickness of the ITO film or of the external gold film. In the corrosion test, ICP-MS results indicated that the gold (Au)/titanium (Ti) films showed relatively excellent chemical stability after exposure to H2SO4 solution with pH 3 at 80 °C.

  10. 75 FR 59744 - Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-28

    ... Commission found that the domestic interested party group response to its notice of institution (75 FR 30434... Plate From Belgium, Italy, Korea, South Africa, and Taiwan AGENCY: United States International Trade... countervailing duty orders on stainless steel plate from Belgium and South Africa and the antidumping duty...

  11. 75 FR 62103 - Stainless Steel Plate in Coils From South Africa: Final Results of Expedited Sunset Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... the Act. See Initiation of Five-Year (``Sunset'') Reviews, 75 FR 30777 (June 2, 2010). The Department... International Trade Administration Stainless Steel Plate in Coils From South Africa: Final Results of Expedited... review of the countervailing duty order (``CVD'') on stainless steel plate in coils from South...

  12. 77 FR 32517 - Stainless Steel Plate in Coils From Belgium: Notice of Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ...The Department of Commerce (the Department) is conducting an administrative review of the antidumping duty order on stainless steel plate in coils (steel plate) from Belgium covering the period of review (POR) May 1, 2010, through April 30, 2011. This review covers one producer/exporter of subject merchandise, Aperam Stainless Belgium N.V. (AS Belgium).\\1\\......

  13. Microstructure and Mechanical Properties of Plasma Arc Brazed AISI 304L Stainless Steel and Galvanized Steel Plates

    NASA Astrophysics Data System (ADS)

    Jin, Yajuan; Li, Ruifeng; Yu, Zhishui; Wang, Yu

    2016-04-01

    Plasma arc brazing is used to join the AISI 304L stainless steel and galvanized steel plate butt joints with the CuSi3Mn1 filler wire. The effect of parameters on weld surface appearance, interfacial microstructure, and composition distribution in the joint was studied. The microhardness and mechanical tests were conducted to determine the mechanical properties of the welded specimens. The results indicated that good appearance, bead shape, and sufficient metallurgical bonding could be obtained when the brazing process was performed with a wire feeding speed of 0.8 m/min, plasma gas flow rate of 3.0 l/min, welding current of 100 A, and welding speed of 27 cm/min. During plasma arc brazing process, the top corner of the stainless steel and galvanized steel plate were heated and melted, and the melted quantity of stainless steel was much more than that of the galvanized steel due to the thermal conductivity coefficient difference between the dissimilar materials. The microhardness test results shows that the microhardness value gradually increased from the side of the galvanized steel to the stainless steel in the joint, and it is good for improving the mechanical properties of joint. The tensile strength was a little higher than that of the brazing filler, and the fracture position of weld joint was at the base metal of galvanized steel plate.

  14. Design parameters of stainless steel plates for maximizing high frequency ultrasound wave transmission.

    PubMed

    Michaud, Mark; Leong, Thomas; Swiergon, Piotr; Juliano, Pablo; Knoerzer, Kai

    2015-09-01

    This work validated, in a higher frequency range, the theoretical predictions made by Boyle around 1930, which state that the optimal transmission of sound pressure through a metal plate occurs when the plate thickness equals a multiple of half the wavelength of the sound wave. Several reactor design parameters influencing the transmission of high frequency ultrasonic waves through a stainless steel plate were examined. The transmission properties of steel plates of various thicknesses (1-7 mm) were studied for frequencies ranging from 400 kHz to 2 MHz and at different distances between plates and transducers. It was shown that transmission of sound pressure through a steel plate showed high dependence of the thickness of the plate to the frequency of the sound wave (thickness ratio). Maximum sound pressure transmission of ∼ 60% of the incident pressure was observed when the ratio of the plate thickness to the applied frequency was a multiple of a half wavelength (2 MHz, 6mm stainless steel plate). In contrast, minimal sound pressure transmission (∼ 10-20%) was measured for thickness ratios that were not a multiple of a half wavelength. Furthermore, the attenuation of the sound pressure in the transmission region was also investigated. As expected, it was confirmed that higher frequencies have more pronounced sound pressure attenuation than lower frequencies. The spatial distribution of the sound pressure transmitted through the plate characterized by sonochemiluminescence measurements using luminol emission, supports the validity of the pressure measurements in this study. PMID:25637292

  15. 76 FR 50495 - Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-15

    ..., 2010 (75 FR 30434) and determined on September 7, 2010 that it would conduct full reviews (75 FR 59744... 27, 2010 (75 FR 81309). The hearing was held in Washington, DC, on May 26, 2011, and all persons who... COMMISSION Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan Determinations On...

  16. 76 FR 53882 - Continuation of Antidumping and Countervailing Duty Orders: Stainless Steel Plate in Coils From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ..., South Africa, and Taiwan, 76 FR 50495 (Aug. 15, 2011), and Stainless Steel Plate in Coils from Belgium... Five-Year (``Sunset'') Review, 75 FR 30777 (June 2, 2010). As a result of its reviews, the Department...: Final Results of the Expedited Sunset Reviews of the Antidumping Duty Orders, 75 FR 61699 (Oct. 6,...

  17. 78 FR 79662 - Stainless Steel Plate in Coils From Belgium: Final Results of Antidumping Duty Administrative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-31

    ... Value: Stainless Steel Plate in Coils from Belgium, 64 FR 15476 (March 31, 1999), as amended by...: Preliminary Results of Antidumping Duty Administrative Review; 2011-2012, 78 FR 34644 (June 10, 2013..., Italy, the Republic of Korea, South Africa, and Taiwan, 64 FR 27756 (May 21, 1999); Notice of...

  18. 76 FR 28809 - Stainless Steel Plate From Belgium; Termination of Five-Year Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... review concerning the countervailing duty order on stainless steel plate from Belgium (75 FR 30777 and 75 FR 30434). On May 5, 2011, Commerce published notice in the Federal Register of the final results of... recurrence of a countervailable subsidy. Therefore, Commerce revoked the countervailing duty order (76...

  19. 75 FR 30434 - Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-01

    ...), and part 207, subparts A, D, E, and F (19 CFR part 207), as most recently amended at 74 FR 2847... FR 25288). On May 21, 1999, Commerce issued antidumping duty orders on imports of certain stainless steel plate from Belgium, Canada, Italy, Korea, South Africa, and Taiwan (64 FR 27756). On March...

  20. Protective coatings on stainless steel bipolar plates for proton exchange membrane (PEM) electrolysers

    NASA Astrophysics Data System (ADS)

    Gago, A. S.; Ansar, S. A.; Saruhan, B.; Schulz, U.; Lettenmeier, P.; Cañas, N. A.; Gazdzicki, P.; Morawietz, T.; Hiesgen, R.; Arnold, J.; Friedrich, K. A.

    2016-03-01

    Proton exchange membrane (PEM) electrolysis is a promising technology for large H2 production from surplus electricity from renewable sources. However, the electrolyser stack is costly due to the manufacture of bipolar plates (BPP). Stainless steel can be used as an alternative, but it must be coated. Herein, dense titanium coatings are produced on stainless steel substrates by vacuum plasma spraying (VPS). Further surface modification of the Ti coating with Pt (8 wt% Pt/Ti) deposited by physical vapour deposition (PVD) magnetron sputtering reduces the interfacial contact resistance (ICR). The Ti and Pt/Ti coatings are characterised by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and X-ray photoelectron microscopy (XPS). Subsequently, the coatings are evaluated in simulated and real PEM electrolyser environments, and they managed to fully protect the stainless steel substrate. In contrast, the absence of the thermally sprayed Ti layer between Pt and stainless steel leads to pitting corrosion. The Pt/Ti coating is tested in a PEM electrolyser cell for almost 200 h, exhibiting an average degradation rate of 26.5 μV h-1. The results reported here demonstrate the possibility of using stainless steel as a base material for the stack of a PEM electrolyser.

  1. Material Corrosion and Plate-Out Test of Types 304L and 316L Stainless Steel

    SciTech Connect

    Zapp, P.E.

    2001-02-06

    Corrosion and plate-out tests were performed on 304L and 316L stainless steel in pretreated Envelope B and Envelope C solutions. Flat coupons of the two stainless steels were exposed to 100 degrees C liquid and to 74 degrees C and 88 degrees C vapor above the solutions for 61 days. No significant corrosion was observed either by weight-loss measurements or by microscopic examination. Most coupons had small weight gains due to plate-out of solids, which remained to some extent even after 24-hour immersion in 1 N nitric acid at room temperature. Plate-out was more significant in the Envelope B coupons, with film thickness from less than 0.001 in. to 0.003-inches.

  2. Failure analysis of stainless steel femur fixation plate.

    PubMed

    Hussain, P B; Mohammad, M

    2004-05-01

    Failure analysis was performed to investigate the failure of the femur fixation plate which was previously fixed on the femur of a girl. Radiography, metallography, fractography and mechanical testing were conducted in this study. The results show that the failure was due to the formation of notches on the femur plate. These notches act as stress raisers from where the cracks start to propagate. Finally fracture occurred on the femur plate and subsequently, the plate failed. PMID:15468877

  3. Brazing open cell reticulated copper foam to stainless steel tubing with vacuum furnace brazed gold/indium alloy plating

    DOEpatents

    Howard, Stanley R.; Korinko, Paul S.

    2008-05-27

    A method of fabricating a heat exchanger includes brush electroplating plated layers for a brazing alloy onto a stainless steel tube in thin layers, over a nickel strike having a 1.3 .mu.m thickness. The resultant Au-18 In composition may be applied as a first layer of indium, 1.47 .mu.m thick, and a second layer of gold, 2.54 .mu.m thick. The order of plating helps control brazing erosion. Excessive amounts of brazing material are avoided by controlling the electroplating process. The reticulated copper foam rings are interference fit to the stainless steel tube, and in contact with the plated layers. The copper foam rings, the plated layers for brazing alloy, and the stainless steel tube are heated and cooled in a vacuum furnace at controlled rates, forming a bond of the copper foam rings to the stainless steel tube that improves heat transfer between the tube and the copper foam.

  4. 76 FR 66271 - Stainless Steel Plate in Coils From Belgium: Notice of Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    ..., and Taiwan, 68 FR 11520 (March 11, 2003); Notice of Amended Antidumping Duty Orders; Certain Stainless Steel Plate in Coils From Belgium, Canada, Italy, the Republic of Korea, South Africa, and Taiwan, 68 FR... Steel Plate in Coils From Belgium, Canada, Italy, the Republic of Korea, South Africa, and Taiwan, 68...

  5. Investigation of residual stresses in a multipass weld in 1 in. stainless steel plate

    SciTech Connect

    Spooner, S.; Fernandez Baca, J.A.; David, S.A.; Hubbard, C.R.; Holden, T.M.; Root, J.H.

    1994-06-01

    Residual stresses and strains were measured in two welded 25-mm thick plates of type 304 stainless steel by the neutron diffraction. The filler metal was type 308 stainless steel and the weld zone had a two phase microstructure in which the austenitic phase lattice parameter differs from the base metal. In these circumstances stain-free samples were taken from the weld zone area for analysis of the lattice parameters and ferrite content using neutron powder diffraction. Corrections for lattice parameter variation were applied permitting the calculation of residual strains and stresses in weld zone, heat affected zone (HAZ) and base metal. One of the two welds was examined without stress relief and the other was given a stress relief treatment consisting of vibration at a frequency below the resonant condition dudng welding. In both plates the largest residual stress component (longitudinal) is found in the fusion zone near the boundary between the weld zone and the heat affected zone. This longitudinal component is 400 {plus_minus} 50 MPa in tension. The normal stresses are generally close to zero although large fluctuations are found in the weld zone. The transverse stresses are as high as 200 MPa in the weld zone and decrease to 50 MPa {plus_minus} 40 MPa. The lattice parameter variation was equivalent to 5 {times} l0{minus}4 compressive strain and the ferrite content approached 9 percent at the center of the weld zone. Variations in residual stresses with thickness through the base metal plate were small. The treated plate and untreated plate showed nearly identical patterns of stress distribution. Differences in the measured stresses between vibratory-stress-relief treated and untreated plates fall within error bars of the stress determination in these particular 25 mm thick 300-type stainless steel plates.

  6. Thermal distortion tests of aluminum and stainless steel plates

    SciTech Connect

    Bielick, E.; Fornek, T.; Spinka, H.; Underwood, D.

    1993-06-25

    An important upgrade to the STAR detector at the Brookhaven National Laboratory RHIC accelerator will be an electromagnetic calorimeter. One design being considered for this calorimeter involves cast lead modules covering {Delta}{phi} = 6{degree} and 0 {le} {vert_bar}{eta}{vert_bar} {le} 1. These modules would consist of alternating layers of lead and sheets of plastic scintillator. The gaps for scintillator between the layers of lead would be created by parallel aluminum plates of thickness {approx_equal}6.6 mm = 0.260in. in the mold for the modules. These plates would need to be machined or ground to be reasonably flat, perhaps to {plus_minus}0.003in., and of uniform thickness from plate to plate. These requirements are imposed by the need to remove the plates from the casting after cooling, and to have good uniformity of the lead layer thickness, which gives good performance for the modules as a calorimeter. Aluminum was chosen for the plates because of its high coefficient of thermal expansion. An important cost in this calorimeter design is associated with the machining or grinding of the plates to proper thickness and flatness. In most cost estimates, it has been assumed that the mold parts could be used many times. This note describes a simple test which was conducted to investigate possible distortions in the plates after repeated heating to temperatures at which the lead would be poured into the mold and cooling.

  7. Ultrasonic butt welding of aluminum, aluminum alloy and stainless steel plate specimens.

    PubMed

    Tsujino, Jiromaru; Hidai, Kazuaki; Hasegawa, Atsushi; Kanai, Ryoichi; Matsuura, Hisanori; Matsushima, Kaoru; Ueoka, Tetsugi

    2002-05-01

    Welding characteristics of aluminum, aluminum alloy and stainless steel plate specimens of 6.0 mm thickness by a 15 kHz ultrasonic butt welding system were studied. There are no detailed welding condition data of these specimens although the joining of these materials are required due to anticorrosive and high strength characteristics for not only large specimens but small electronic parts especially. These specimens of 6.0 mm thickness were welded end to end using a 15 kHz ultrasonic butt welding equipment with a vibration source using eight bolt-clamped Langevin type PZT transducers and a 50 kW static induction thyristor power amplifier. The stainless steel plate specimens electrolytically polished were joined with welding strength almost equal to the material strength under rather large vibration amplitude of 25 microm (peak-to-zero value), static pressure 70 MPa and welding time of 1.0-3.0 s. The hardness of stainless steel specimen adjacent to a welding surface increased about 20% by ultrasonic vibration. PMID:12159968

  8. Numerical Analysis of Residual Stress for Copper Base Brazed Stainless Steel Plate-Fin Structure

    NASA Astrophysics Data System (ADS)

    Xie, Qiaoyun; Ling, Xiang

    2010-07-01

    Copper base stainless steel plate-fin structure has been widely used as a heat exchanger in many fields. The nonlinear thermal reaction on the residual stress in brazing process of the plate-fin structure was studied in this paper. A finite element model (FEM) was proposed to simulate the heat transfer and the sequential residual stress generated in the plate-fin and filler metals based on thermal elastic-plastic theory. By the stress distribution in four paths marked in the structure obtained from FEM results, it is found that the maximum residual tensile stress occurs in the brazed joint next to the plate side and a crack would initiate in this region. Also, the first principle stresses of reference nodes were calculated and the conclusion is consistent with the simulation results. These results would provide some constructive instructions in the practical brazing procedure.

  9. Brazing titanium to stainless steel

    NASA Technical Reports Server (NTRS)

    Batista, R. I.

    1980-01-01

    Titanium and stainless-steel members are usually joined mechanically for lack of any other effective method. New approach using different brazing alloy and plating steel member with nickel resolves problem. Process must be carried out in inert atmosphere.

  10. Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates

    NASA Astrophysics Data System (ADS)

    Yang, B.; Brady, M. P.; Wang, H.; Turner, J. A.; More, K. L.; Young, D. J.; Tortorelli, P. F.; Payzant, E. A.; Walker, L. R.

    Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr 2N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, which prevented the internal nitridation typically observed for these alloys, and resulted in external Cr-nitride layer formation. The addition of V to the alloy, which resulted in the initial formation of V 2O 3-Cr 2O 3, was found to enhance this effect, by making the initially formed oxide more amenable to subsequent nitridation. The Cr-nitride surface layer formed on model V-modified Fe-27Cr alloys exhibited excellent corrosion resistance and low interfacial contact resistance under simulated PEMFC bipolar plate conditions.

  11. Quantitative histological evaluation of early fracture healing of cortical bones immobilized by stainless steel and composite plates.

    PubMed

    Akeson, W H; Woo, S L; Coutts, R D; Matthews, J V; Gonsalves, M; Amiel, D

    1975-11-24

    Internal fixation devices of less bending stiffness than conventional plates made of stainless steel or vitallium were compared with conventional plates in a study of fracture healing. The material for this investigation was a fine graphite fiber reinforced methyl methacrylate resin composite with a modulus of elasticity approximately ten times less than that of stainless steel. Osteotomies were performed on canine radii. Internal fixation was accomplished by means of a composite plate on the left side, and a stainless steel plate on the right. Clinical assessment, as well as biomechanical and quantitative histological techniques, were used to compare osteotomy healing of the two sides. At four months, all osteotomies had healed and the bioengineering tests showed radii from the two sides had equivalent strength. However, significantly less cortical porosity was found in the side with the composite plate (6.8 per cent), as compared to that of the stainless steel plated side (14 per cent). These results suggest that a less stiff fixation plate may have some advantage in the treatment of long bone fracture if there is no implant failure, and if union rates are equivalent. PMID:1201463

  12. Residual Stresses in LENS-Deposited AISI 410 Stainless Steel Plates

    SciTech Connect

    Wang, L; Felicellli, S D; Pratt, Phillip R

    2008-01-01

    The residual stress in thin plate components deposited by the laser engineered net shaping (LENS{reg_sign}) process was investigated experimentally and numerically. Neutron diffraction mapping was used to characterize the residual stress in LENS-deposited AISI 410 stainless steel thin wall plates. Using the commercial welding software SYSWELD, a thermo-mechanical three-dimensional finite element model was developed, which considers also the effect of metallurgical phase transformations. The model was employed to predict the temperature history and the residual stress field during the LENS process. Several simulations were performed with the geometry and process parameters that were used to build the experimental samples. The origin of the residual stress distribution is discussed based on the thermal histories of the samples, and the modeling results are compared with measurements obtained by neutron diffraction mapping.

  13. SnO2:F Coated Duplex Stainless Steel for PEM Fuel Cell Bipolar Plates

    SciTech Connect

    Wang, H.; Turner, J. A.

    2008-01-01

    Duplex 2205 stainless steel was deposited with 0.6 {micro}m thick SnO2:F coating; coated steel was characterized for PEMFC bipolar plate application. Compared with bare alloy, interfacial contact resistance (ICR) values of the coated 2205 steel are higher. SnO2:F coating adds its own resistance to the air-formed film on the steel. In a PEMFC anode environment, a current peak of ca. 25 {micro}A/cm2 registered at ca. 30 min for coated 2205 steel. It stabilized at ca. 2.0 {approx} -1.0 {micro}A/cm2. This peak is related to the complicated process of coating dissolution and oxide-layer formation. Anodic-cathodic current transfer occurred at ca. 200 min polarization. In a PEMFC cathode environment, current was stable immediately after polarization. The stable current was ca. 0.5 {approx} 2.0 {micro}A/cm2 during the entire polarization period. AES depth profiles with tested samples and ICP analysis with the tested solutions confirmed the excellent corrosion resistance of the SnO2:F coated 2205 alloy in simulated PEMFC environments.

  14. Effect of grain refinement and electrochemical nitridation on corrosion resistance of the 316L stainless steel for bipolar plates in PEMFCs environment

    NASA Astrophysics Data System (ADS)

    Jinlong, Lv; Tongxiang, Liang; Hongyun, Luo

    2015-10-01

    The stain-induced nanocrystalline α'-martensite was obtained by cryogenic cold rolling at liquid-nitrogen temperature for 316L stainless steel. The electrochemical results showed nanocrystalline 316L stainless steel deteriorated its corrosion resistance in a typical proton exchange membrane fuel cell environment compared with coarse grained one. However, comparing with electrochemically nitrided coarse grained stainless steel, electrochemically nitrided nanocrystalline stainless steel improved significantly corrosion resistance in the same environment, which was supported further by Mott-Shottky analysis. X-ray photoelectron spectroscopy analysis revealed that the nanocrystalline promoted the enrichment of nitrogen and chromium and inhibited form of NH3 on the surface, which could significantly improve the corrosion resistance of the 316L stainless steel. The present study showed that the electrochemically nitrided 316L stainless steel was more suitable for the bipolar plates in proton exchange membrane fuel cell environment than the untreated one, especially for nanocrystalline stainless steel.

  15. 78 FR 30271 - Stainless Steel Plate in Coils From Belgium, South Africa, and Taiwan: Notice of Court Decision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-22

    ... Orders: Stainless Steel Plate in Coils from Belgium, Italy and South Africa, 64 FR 25288 (May 11, 1999... Korea, South Africa, and Taiwan, 64 FR 27756 (May 21, 1999); Notice of Amended Antidumping Duty Orders..., and Taiwan, 68 FR 11520 (March 11, 2003); and Notice of Amended Countervailing Duty Orders;...

  16. 75 FR 81966 - Stainless Steel Plate in Coils From Belgium: Extension of Time Limit for Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ... Countervailing Duty Administrative Reviews and Requests for Revocation in Part, 75 FR 37759, 37763 (June 30, 2010... International Trade Administration Stainless Steel Plate in Coils From Belgium: Extension of Time Limit for.... Statutory Time Limits Section 751(a)(3)(A) of the Tariff Act of 1930, as amended (``the Act''), requires...

  17. 75 FR 67346 - Stainless Steel Plate in Coils from South Korea: Correction to Final Results of the Expedited...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... International Trade Administration Stainless Steel Plate in Coils from South Korea: Correction to Final Results... Co., Ltd. (POSCO), as well as the ``all others'' rate for South Korea. Specifically, the weighted-average margin for POSCO and the ``all others'' rate for South Korea, listed as 16.26 percent, should...

  18. 76 FR 25666 - Stainless Steel Plate in Coils from Belgium: Final Results of Full Sunset Review and Revocation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ... Initiation of Five-Year (``Sunset'') Review, 75 FR 30777 (June 2, 2010). ] Within the deadline specified in... From Belgium: Preliminary Results of Full Sunset Review, 75 FR 81217, 81218 (December 27, 2010... Duty Orders on Certain Stainless Steel Plate in Coils From Belgium, Italy, and South Africa, 70...

  19. 76 FR 45511 - Stainless Steel Plate in Coils From Belgium: Notice of Initiation of Antidumping Duty Changed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-29

    ... Reviews and Request for Revocation in Part 76 FR 37781 (June 28, 2011).\\2\\ \\1\\ See Antidumping Duty Orders..., and Taiwan, 64 FR 27756 (May 21, 1999); Notice of Amended Antidumping Duty Orders; Certain Stainless Steel Plate in Coils From Belgium, Canada, Italy, the Republic of Korea, South Africa, and Taiwan, 68...

  20. Surface temperature distribution of GTA weld pools on thin-plate 304 stainless steel

    SciTech Connect

    Zacharia, T.; David, S.A.; Vitek, J.M.; Kraus, H.G.

    1995-11-01

    A transient multidimensional computational model was utilized to study gas tungsten arc (GTA) welding of thin-plate 304 stainless steel (SS). The model eliminates several of the earlier restrictive assumptions including temperature-independent thermal-physical properties. Consequently, all important thermal-physical properties were considered as temperature dependent throughout the range of temperatures experienced by the weld metal. The computational model was used to predict surface temperature distribution of the GTA weld pools in 1.5-mm-thick AISI 304 SS. The welding parameters were chosen so as to correspond with an earlier experimental study that produced high-resolution surface temperature maps. One of the motivations of the present study was to verify the predictive capability of the computational model. Comparison of the numerical predictions and experimental observations indicate excellent agreement, thereby verifying the model.

  1. Investigation of a fatigue failure in a stainless steel femoral plate.

    PubMed

    Marcomini, J B; Baptista, C A R P; Pascon, J P; Teixeira, R L; Reis, F P

    2014-10-01

    Surgical implants are exposed to severe working conditions and therefore a wide range of failure mechanisms may occur, including fatigue, corrosion, wear, fretting and combinations of them. The mechanical failures of metallic implants may also be influenced by several other factors, including the design, material, manufacturing, installation, postoperative complications and misuse. An 83-year-old patient suffered an oblique femoral shaft fracture due to a fall at home. A stainless steel locking compression plate (LCP) employed in the fracture reduction failed after four months and was sent back to the producer. A second LCP of the same type was implanted and also failed after six months. A failure analysis of the second femoral LCP is performed in this paper. The results demonstrate that poor material quality was decisive to the failure. The chemical analysis revealed a high P content in the steel, which is not in accordance to the standards. A combination of factors lead to LCP fracture and these include: brittle crack initiation due to phosphorus, segregation at grain boundaries, crack propagation due to cyclic loading and final fast fracture favored by the loss of ductility due to cold work. PMID:25023519

  2. Residual stresses in a multi-pass weld in an austenitic stainless steel plate before and after thermal stress relief

    SciTech Connect

    Spooner, S.; Wang, X.L.; Hubbard, C.R.; David, S.A.

    1994-06-01

    Changes in residual stresses due to thermal stress relief were determined in a welded 1/2 in. thick 304 stainless steel plate from two residual stress maps determined with the neutron diffraction technique. The 304 stainless plate was made from two 6 {times} 12 {times} 1/2 in. pieces joined along the length by a gas tungsten arc welding process. Multi-pass welds were made with a semiautomatic welding machine employing cold-wire feed of type 308 stainless steel filler alloy. The thermal stress relief treatment consisted of heating to 1150 F, holding for one hour at temperature and then air cooling. Strain components were measured along the weld direction (longitudinal), perpendicular to the weld line in the plate (transverse), and normal to the plate. Measurements were confined to the plane bisecting the weld at the center of the plate. The strain components were converted to stresses assuming that the measured strains were along the principal axes of the strain tensor. Parameters used in the calculation were E=224 GPa and v=0.25. As-welded longitudinal stresses are compressive in the base metal and become strongly tensile through the heat affected zone and into the fusion zone. The transverse stresses follow the longitudinal trend but with a lower magnitude while the normal stresses are small throughout. The stress relief treatment reduced the magnitudes of all the stresses. In the weld zone the longitudinal stress was lowered by 30% and the spatial range of residual stresses was reduced as well.

  3. Properties of graphite-stainless steel composite in bipolar plates in simulated anode and cathode environments of PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Włodarczyk, Renata

    2014-09-01

    The use of a graphite-stainless steel composite as bipolar plates (BP) in polymer electrolyte membrane fuel cells (PEMFCs) has been evaluated. The study covers measurements of mechanical properties, microstructural examination, analysis of surface profile, wettability, porosity and corrosion resistance of the composite. The corrosion properties of the composite were examined in 0.1 mol·dm-3 H2SO4 + 2 ppm F- saturated with H2 or with O2 and in solutions with different pH: in Na2SO4+ 2 ppm F- (pH = 1.00, 3.00, 5.00) at 80 °C. The performed tests indicate that the graphite modified with stainless steel can be a good choice to be used as a bipolar plate in PEM fuel cells.

  4. 75 FR 61699 - Stainless Steel Plate in Coils From Belgium, Italy, South Africa, South Korea, and Taiwan: Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-06

    ...On June 2, 2010, the Department of Commerce (the Department) initiated sunset reviews of the antidumping duty orders on stainless steel plate in coils (SSPC) from Belgium, Italy, South Africa, South Korea, and Taiwan, pursuant to section 751(c) of the Tariff Act of 1930, as amended (the Act). The Department has conducted expedited (120-day) sunset reviews for these orders pursuant to 19 CFR......

  5. Stainless steel versus titanium volar multi-axial locking plates for fixation of distal radius fractures: a randomised clinical trial

    PubMed Central

    2014-01-01

    Background Distal radius fractures are among the most common fractures seen in the hospital emergency department. Of these, over 40% are considered unstable and require some form of fixation. In recent years with the advent of low profile plating, open reduction and internal fixation (ORIF) using volar plates has become the surgical treatment of choice in many hospitals. However, it is currently unknown which plating system has the lowest complication rate and/or superior clinical and radiological outcomes following surgery. Few studies have compared different types of plates, which may have various features, different plate and screw designs or may be manufactured from different materials (for example, stainless steel or titanium). This study will specifically investigate and compare the clinical and radiological outcomes and complication rates of two commonly used volar plating systems for fixation of distal radius fractures: one made from stainless steel (Trimed™ Volar Plate, Trimed™, California, USA) and the other made from titanium (Medartis® Aptus Volar Plate, Medartis®, Basel, Switzerland). The primary aim of this study is to determine if there is a difference on the Patient Reported Wrist Evaluation six months following ORIF using a volar plate for adult patients with a distal radius fracture. Methods/Design This study will implement a randomized prospective clinical trial study design evaluating the outcomes of two different types of volar plates: one plate manufactured from stainless steel (Trimed™ Volar Plate) and one plate manufactured from titanium (Medartis® Aptus Volar Plate). The surgery will be performed at a major trauma hospital in Brisbane, Australia. Outcome measures including function, adverse events, range of movement, strength, disability, radiological findings and health-related quality of life will be collected at 6 weeks, 3, 6, 12 and 24 months following surgery. A parallel economic analysis will also be performed. This

  6. Electrochemical behaviour and surface conductivity of niobium carbide-modified austenitic stainless steel bipolar plate

    NASA Astrophysics Data System (ADS)

    Wang, Lixia; Sun, Juncai; Kang, Bin; Li, Song; Ji, Shijun; Wen, Zhongsheng; Wang, Xiaochun

    2014-01-01

    A niobium carbide diffusion layer with a cubic NbC phase surface layer (∼6 μm) and a Nb and C diffusion subsurface layer (∼1 μm) is fabricated on the surface of AISI 304 stainless steel (304 SS) bipolar plate in a proton exchange membrane fuel cell (PEMFC) using plasma surface diffusion alloying. The electrochemical behaviour of the niobium carbide diffusion-modified 304 SS (Nb-C 304 SS) is investigated in simulated PEMFC environments (0.5 M H2SO4 and 2 ppm HF solution at 80 °C). Potentiodynamic, potentiostatic polarisation and electrochemical impedance spectroscopy measurements reveal that the niobium carbide diffusion layer considerably improves the corrosion resistance of 304 SS compared with untreated samples. The corrosion current density of Nb-C 304 SS is maintained at 0.058 μA cm-2 and 0.051 μA cm-2 under simulated anodic and cathodic conditions, respectively. The interfacial contact resistance of Nb-C 304 SS is 8.47 mΩ cm2 at a compaction force of 140 N cm-2, which is significantly lower than that of the untreated sample (100.98 mΩ cm2). Moreover, only a minor increase in the ICR of Nb-C 304 SS occurs after 10 h potentiostatic tests in both cathodic and anodic environments.

  7. Multilayer graphene for long-term corrosion protection of stainless steel bipolar plates for polymer electrolyte membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Stoot, Adam C.; Camilli, Luca; Spiegelhauer, Susie-Ann; Yu, Feng; Bøggild, Peter

    2015-10-01

    Motivated by similar investigations recently published (Pu et al., 2015), we report a comparative corrosion study of three sets of samples relevant as bipolar plates for polymer electrolyte fuel cells: stainless steel, stainless steel with a nickel seed layer (Ni/SS) and stainless steel with Ni seed layer coated by a multi-layered graphene thin film (G/Ni/SS). The graphene film, synthesized by chemical vapour deposition (CVD), has a moderate amount of defects according to Raman spectroscopy. Short/medium-term corrosion test shows no significant advantage of using G/Ni/SS rather than Ni/SS, both samples exhibiting a similar trend, thus questioning the short-term positive effect of graphene coatings. However, partial immersion in boiling seawater for three weeks reveals a clear superiority of the graphene coating with respect to steel just protected by Ni. After the test, the graphene film is still intact with unchanged defect density. Our results show that even non-perfect multilayer graphene films can considerably increase the lifetime of future-generation bipolar plates for fuel cells.

  8. Supertough Stainless Bearing Steel

    NASA Technical Reports Server (NTRS)

    Olson, Gregory B.

    1995-01-01

    Composition and processing of supertough stainless bearing steel designed with help of computer-aided thermodynamic modeling. Fracture toughness and hardness of steel exceeds those of other bearing steels like 440C stainless bearing steel. Developed for service in fuel and oxidizer turbopumps on Space Shuttle main engine. Because of strength and toughness, also proves useful in other applications like gears and surgical knives.

  9. Tensile Stress-Strain Results for 304L and 316L Stainless-Steel Plate at Temperature

    SciTech Connect

    R. K. Blandford; D. K. Morton; S. D. Snow; T. E. Rahl

    2007-07-01

    The Idaho National Laboratory (INL) is conducting moderate strain rate (10 to 200 per second) research on stainless steel materials in support of the Department of Energy’s (DOE) National Spent Nuclear Fuel Program (NSNFP). For this research, strain rate effects are characterized by comparison to quasi-static tensile test results. Considerable tensile testing has been conducted resulting in the generation of a large amount of basic material data expressed as engineering and true stress-strain curves. The purpose of this paper is to present the results of quasi-static tensile testing of 304/304L and 316/316L stainless steels in order to add to the existing data pool for these materials and make the data more readily available to other researchers, engineers, and interested parties. Standard tensile testing of round specimens in accordance with ASTM procedure A 370-03a were conducted on 304L and 316L stainless-steel plate materials at temperatures ranging from -20 °F to 600 °F. Two plate thicknesses, eight material heats, and both base and weld metal were tested. Material yield strength, Young’s modulus, ultimate strength, ultimate strain, failure strength and failure strain were determined, engineering and true stress-strain curves to failure were developed, and comparisons to ASME Code minimums were made. The procedures used during testing and the typical results obtained are described in this paper.

  10. Coating stainless steel plates with Ag/TiO2 for chlorpyrifos decontamination

    NASA Astrophysics Data System (ADS)

    Abdel Fattah, Wafa I.; Gobara, Mohammed M.; El-Hotaby, Walid; Mostafa, Sherif F. M.; Ali, Ghareib W.

    2016-05-01

    Spray coatings of either nanosilver (Ag), titanium (TiO2) or nanosilver titanium (Ag/TiO2) on stainless steel substrates prepared by sol–gel process were successfully achieved. The efficiency of the Ag/TiO2 coat onto 316 stainless steel surface towards cloropyrifos degradation as a chemical warfare agent (CWA) was proved. The crystalline structure and morphological characterization, as well as surface roughness measurements, were assessed. X-ray diffraction results proved the crystalline TiO2 anatase phase. The uniform distribution of Ag along with TiO2 nanoparticles was evidenced through transmission electron microscopy and scanning electron microscopy mapping. The hydrophilic nature of individual Ag, TiO2 and Ag/TiO2 coats was proved by contact angle measurements. The loading of Ag nanoparticles influenced positively the Ag/TiO2 coats surface roughness. The photocatalytic cloropyrifos degradation achieved about 50% within one-hour post UV treatment proving, therefore, the promising Ag/TiO2 continued decontamination efficiency. In conclusion, tuning the physical and morphological properties of TiO2 coated on stainless steel surface could be significantly enhanced by Ag nanoparticles incorporation. The developed Ag/TiO2 coat could be conveniently applied as CWA decontaminant.

  11. An electrochemical treatment to improve corrosion and contact resistance of stainless steel bipolar plates used in polymer electrolyte fuel cells

    NASA Astrophysics Data System (ADS)

    Gabreab, Ebrahim M.; Hinds, Gareth; Fearn, Sarah; Hodgson, David; Millichamp, Jason; Shearing, Paul R.; Brett, Daniel J. L.

    2014-01-01

    An electrochemical surface treatment is presented that improves the properties of stainless steel (316SS) used as bipolar plates for polymer electrolyte fuel cells (PEFCs). The process is an anodic treatment, whereby the material is polarised beyond the transpassive region. Potentiodynamic corrosion testing, chemical and morphological surface characterisation and interfacial contact resistance measurements indicate that the improved properties of 316SS are primarily a consequence of an enrichment of Cr at the near-surface of the material. The surface treatment increases the corrosion resistance and significantly reduces interfacial contact resistance.

  12. Graphene grown on stainless steel as a high-performance and ecofriendly anti-corrosion coating for polymer electrolyte membrane fuel cell bipolar plates

    NASA Astrophysics Data System (ADS)

    Pu, Nen-Wen; Shi, Gia-Nan; Liu, Yih-Ming; Sun, Xueliang; Chang, Jeng-Kuei; Sun, Chia-Liang; Ger, Ming-Der; Chen, Chun-Yu; Wang, Po-Chiang; Peng, You-Yu; Wu, Chia-Hung; Lawes, Stephen

    2015-05-01

    In this study, the growth of graphene by chemical vapor deposition (CVD) on SUS304 stainless steel and on a catalyzing Ni/SUS304 double-layered structure was investigated. The results indicated that a thin and multilayered graphene film can be continuously grown across the metal grain boundaries of the Ni/SUS304 stainless steel and significantly enhance its corrosion resistance. A 3.5 wt% saline polarization test demonstrated that the corrosion currents in graphene-covered SUS304 were improved fivefold relative to the corrosion currents in non-graphene-covered SUS304. In addition to enhancing the corrosion resistance of stainless steel, a graphene coating also ameliorates another shortcoming of stainless steel in a corrosive environment: the formation of a passive oxidation layer on the stainless steel surface that decreases conductivity. After a corrosion test, the graphene-covered stainless steel continued to exhibit not only an excellent low interfacial contact resistance (ICR) of 36 mΩ cm2 but also outstanding drainage characteristics. The above results suggest that an extremely thin, lightweight protective coating of graphene on stainless steel can act as the next-generation bipolar plates of fuel cells.

  13. Chromium-Makes stainless steel stainless

    USGS Publications Warehouse

    Kropschot, S.J.; Doebrich, Jeff

    2010-01-01

    Chromium, a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point, is a silvery white, hard, and bright metal plating on steel and other material. Commonly known as chrome, it is one of the most important and indispensable industrial metals because of its hardness and resistance to corrosion. But it is used for more than the production of stainless steel and nonferrous alloys; it is also used to create pigments and chemicals used to process leather.

  14. Elastomer-induced crevice corrosion and stress corrosion cracking of stainless steel heat exchanger plates in sour amine service

    SciTech Connect

    Hay, M.G.; Baron, J.J.; Moffat, T.A.

    1996-08-01

    Types S31600 and S31254 stainless steel heat exchanger plates have suffered crevice corrosion and stress corrosion cracking under gaskets in rich amine service in a sour gas plant. The gasket material, ethylene-propylene-diene monomer (EPDM), has been used successfully for many years at other sour gas plants. Laboratory testing has duplicated the corrosion observed and shown that the mechanism is synergistic sulfide-halide attack. The use of a bromine plus chlorine-activated curing system for the EPDM rubber gaskets provided the necessary halides. Laboratory testing identified some nickel-based superalloys which were resistant to this corrosion and also demonstrated that essentially halogen-free, peroxide-cured EPDM gaskets do not cause attack of S31600 or S31254. The heat exchanger packs were replaced with S31600 plates and peroxide-cured EPDM gaskets having a specified total halogen concentration of 200 ppm maximum. Field operating experience has been excellent.

  15. Pre-oxidized and nitrided stainless steel alloy foil for proton exchange membrane fuel cell bipolar plates. Part 2: Single-cell fuel cell evaluation of stamped plates

    NASA Astrophysics Data System (ADS)

    Toops, Todd J.; Brady, Michael P.; Tortorelli, Peter F.; Pihl, Josh A.; Estevez, Francisco; Connors, Daniel; Garzon, Fernando; Rockward, Tommy; Gervasio, Don; Mylan, William; Kosaraju, Sree Harsha

    Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr 2N, CrN, TiN, V 2N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of proton exchange membrane (PEM) single-cell fuel cell studies of stamped and pre-oxidized/nitrided developmental Fe-20Cr-4V weight percent (wt.%) and commercial type 2205 stainless steel alloy foils. The single-cell fuel cell behavior of the stamped and pre-oxidized/nitrided material was compared to as-stamped (no surface treatment) 904L, 2205, and Fe-20Cr-4V stainless steel alloy foils and machined graphite of similar flow field design. The best fuel cell behavior among the alloys was exhibited by the pre-oxidized/nitrided Fe-20Cr-4V, which exhibited ∼5-20% better peak power output than untreated Fe-20Cr-4V, 2205, and 904L metal stampings. Durability was assessed for pre-oxidized/nitrided Fe-20Cr-4V, 904L metal, and graphite plates by 1000+ h of cyclic single-cell fuel cell testing. All three materials showed good durability with no significant degradation in cell power output. Post-test analysis indicated no metal ion contamination of the membrane electrode assemblies (MEAs) occurred with the pre-oxidized and nitrided Fe-20Cr-4V or graphite plates, and only a minor amount of contamination with the 904L plates.

  16. Corrosive characteristics of surface-modified stainless steel bipolar plate in solid polymer fuel cell

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaowen; Wang, Lixia; Sun, Juncai

    2015-03-01

    In this paper, corrosion behavior of an AISI 304 stainless steel modified by niobium or niobium nitride (denoted as niobized 304 SS and Nb-N 304 SS, respectively) is investigated in simulated solid polymer fuel cell (SPFC) operating conditions. Potentiodynamic polarizations show that the corrosion potentials of surface modified 304 SS shift to positive direction while the corrosion current densities decrease greatly comparing with the bare 304 SS in simulated anodic SPFC environments. The order of corrosive resistance in corrosive potential, corrosive current density and pitting potential is: Nb-N 304 SS > niobized 304 SS > bare 304 SS. In the methanol-fueled SPFC operating conditions, the results show that the corrosion resistance of bare and niobized 304 SS increases with the methanol concentration increasing in the test solutions.

  17. Lanthanum oxide-coated stainless steel for bipolar plates in solid oxide fuel cells (SOFCs)

    NASA Astrophysics Data System (ADS)

    Yoon, Jong Seol; Lee, Jun; Hwang, Hae Jin; Whang, Chin Myung; Moon, Ji-Woong; Kim, Do-Hyeong

    Solid oxide fuel cells typically operate at temperatures of about 1000 °C. At these temperatures only ceramic interconnects such as LaCrO 3 can be employed. The development of intermediate-temperature solid oxide fuel cells (IT-SOFCs) can potentially bring about reduced manufacturing costs as it makes possible the use of an inexpensive ferritic stainless steel (STS) interconnector. However, the STS suffers from Cr 2O 3 scale formation and a peeling-off phenomenon at the IT-SOFC operating temperature in an oxidizing atmosphere. Application of an oxidation protective coating is an effective means of providing oxidation resistance. In this study, we coated an oxidation protective layer on ferritic stainless steel using a precursor solution prepared from lanthanum nitrate, ethylene glycol, and nitric acid. Heating the precursor solution at 80 °C yielded a spinable solution for coating. A gel film was coated on a STS substrate by a dip coating technique. At the early stage of the heat-treatment, lanthanum-containing oxides such as La 2O 3 and La 2CrO 6 formed, and as the heat-treatment temperature was increased, an oxidation protective perovskite-type LaCrO 3 layer was produced by the reaction between the lanthanum-containing oxide and the Cr 2O 3 scale on the SUS substrate. As the concentration of La-containing precursor solution was increased, the amount of La 2O 3 and La 2CrO 6 phases was gradually increased. The coating layer, which was prepared from a precursor solution of 0.8 M, was composed of LaCrO 3 and small amounts of (Mn,Cr)O 4 spinel. A relatively dense coating layer without pin-holes was obtained by heating the gel coating layer at 1073 K for 2 h. Microstructures and oxidation behavior of the La 2O 3-coated STS444 were investigated.

  18. Conductive and corrosion behaviors of silver-doped carbon-coated stainless steel as PEMFC bipolar plates

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Xu, Hong-feng; Fu, Jie; Tian, Ying

    2016-07-01

    Ni-Cr enrichment on stainless steel SS316L resulting from chemical activation enabled the deposition of carbon by spraying a stable suspension of carbon nanoparticles; trace Ag was deposited in situ to prepare a thin continuous Ag-doped carbon film on a porous carbon-coated SS316L substrate. The corrosion resistance of this film in 0.5 mol·L-1 H2SO4 solution containing 5 ppm F- at 80°C was investigated using polarization tests. The results showed that the surface treatment of the SS316L strongly affected the adhesion of the carbon coating to the stainless steel. Compared to the bare SS316L, the Ag-doped carbon-coated SS316L bipolar plate was remarkably more stable in both the anode and cathode environments of proton exchange membrane fuel cell (PEMFC) and the interface contact resistance between the specimen and Toray 060 carbon paper was reduced from 333.0 mΩ·cm2 to 21.6 mΩ·cm2 at a compaction pressure of 1.2 MPa.

  19. Is stainless steel really "stainless"?

    PubMed

    Porteous, Joan

    2011-06-01

    Initial purchase and replacement costs for surgical instrumentation are significant components in today's operating room budgets. OR staff and medical device reprocessing personnel work together as a team to ensure effective management of this valuable commodity. The purpose of this article is to discuss the composition of stainless steel surgical instruments, to identify processes to minimize damage to instruments caused by staining, corrosion, and pitting, and to utilize that information to describe effective measures to manage instrumentation in both the OR and reprocessing areas. PMID:21823503

  20. Improved corrosion resistance and interfacial contact resistance of 316L stainless-steel for proton exchange membrane fuel cell bipolar plates by chromizing surface treatment

    NASA Astrophysics Data System (ADS)

    Lee, S. B.; Cho, K. H.; Lee, W. G.; Jang, H.

    The electrochemical performance and electrical contact resistance of chromized 316 stainless-steel (SS) are investigated under simulated operating condition in a proton-exchange membrane fuel cell (PEMFC). The corrosion resistance of the chromized stainless steel is assessed by potentiodynamic and potentiostatic tests and the interfacial contact resistance (ICR) is examined by measuring the electrical contact resistance as a function of the compaction force. The results show that the chromizing surface treatment improves the corrosion resistance of the stainless steel due to the high-chromium concentration in the diffuse coating layer. On the other hand, the excess Chromium content on the surface increases the contact resistance of the steel plate to a level that is excessively high for commercial applications. This study examines the root cause of the high-contact resistance after chromizing and reports the optimum process to improve the corrosion resistance without sacrificing the ICR by obtaining a chrome carbide on the outer layer.

  1. Torsional moment to failure for carbon fibre polysulphone expandable rivets as compared with stainless steel screws for carbon fibre-reinforced epoxy fracture plate fixation.

    PubMed

    Sell, P J; Prakash, R; Hastings, G W

    1989-04-01

    A method of securing carbon fibre-reinforced epoxy bone plates with carbon fibre polysulphone expanding rivets was investigated. Six carbon fibre-reinforced epoxy bone plates were secured to rods with carbon fibre polysulphone rivets and six were secured with standard cortical stainless steel screws. These constructions were then subjected to pure torsional load to failure. The carbon fibre expandable rivets failed at a greater torsional moment. PMID:2720038

  2. Electroless Ni-Cu-P plating onto open cell stainless steel foam

    NASA Astrophysics Data System (ADS)

    Abdel Aal, A.; Shehata Aly, M.

    2009-04-01

    Metallic foams with a high fraction of porosity, low density and high energy absorption capacity, are a rapidly emerging class of novel ultralightweight materials for various engineering applications. Development of these materials with Ni-Cu-P coatings is expected to widespread their industrial utilizations. This article aims to apply Ni-Cu-P coatings onto open cell stainless steel foams from Ni-P bath containing CuSO 4·5H 2O as a source of Cu ions. Scanning electron microscopy and energy dispersive analysis were used to investigate the microstructure and chemical composition of the deposited coatings, respectively. The influence of CuSO 4·5H 2O addition on the deposition rate, chemical composition and surface morphology of coatings was studied. The corrosion performance of coated foam was examined in 1 M HCl using weight loss technique. The results revealed that wt.% of Cu in deposit increases with CuSO 4·5H 2O concentration, while wt.% of Ni and P is reduced. Better corrosion resistance, finer-grained deposit and lower deposition rate were observed by increasing Cu content into Ni-P matrix.

  3. Articles comprising ferritic stainless steels

    DOEpatents

    Rakowski, James M.

    2016-06-28

    An article of manufacture comprises a ferritic stainless steel that includes a near-surface region depleted of silicon relative to a remainder of the ferritic stainless steel. The article has a reduced tendency to form an electrically resistive silica layer including silicon derived from the steel when the article is subjected to high temperature oxidizing conditions. The ferritic stainless steel is selected from the group comprising AISI Type 430 stainless steel, AISI Type 439 stainless steel, AISI Type 441 stainless steel, AISI Type 444 stainless steel, and E-BRITE.RTM. alloy, also known as UNS 44627 stainless steel. In certain embodiments, the article of manufacture is a fuel cell interconnect for a solid oxide fuel cell.

  4. Solderability study of 63Sn-37Pb on zinc-plated and cadmium-plated stainless steel for the MC4636 lightning arrestor connector.

    SciTech Connect

    Lopez, Edwin Paul; Vianco, Paul Thomas; Rejent, Jerome Andrew; Martin, Joseph J.

    2004-06-01

    Cadmium plating on metal surfaces is commonly used for corrosion protection and to achieve good solderability on the 304L stainless steel shell of the MC4636 lightning arrestor connector (LAC) for the W76-1 system. This study examined the use of zinc as a potential substitute for the cadmium protective surface finish. Tests were performed with an R and RMA flux and test temperatures of 230 C, 245 C, and 260 C. Contact angle, {theta}{sub c}, served as the generalized solderability metric. The wetting rate and wetting time parameters were also collected. The solderability ({theta}{sub c}) of the Erie Plating Cd/Ni coatings was better than that of similar Amphenol coatings. Although the {theta}{sub c} data indicated that both Cd/Ni platings would provide adequate solderability, the wetting rate and wetting time data showed the Amphenol coatings to have better performance. The Zn/Ni coatings exhibited non-wetting under all flux and temperature conditions. Based on the results of these tests, it has been demonstrated that zinc plating is not a viable alternate to cadmium plating for the LAC connectors.

  5. Pre-Oxidized and Nitrided Stainless Steel Foil for Proton Exchange Membrane Fuel Cell Bipolar Plates: Part 1 Corrosion, Interfacial Contact Resistance, and Surface Structure

    SciTech Connect

    Brady, Michael P; Wang, Heli; Turner, John; Meyer III, Harry M; More, Karren Leslie; Tortorelli, Peter F; McCarthy, Brian D

    2010-01-01

    Thermal (gas) nitridation of stainless steels can yield low interfacial contact resistance (ICR), electrically-conductive and corrosion-resistant nitride containing surfaces (Cr2N, CrN, TiN, V2N, VN, etc) of interest for fuel cells, batteries, and sensors. This paper presents the results of scale up studies to determine the feasibility of extending the nitridation approach to thin 0.1 mm stainless steel alloy foils for proton exchange membrane fuel cell (PEMFC) bipolar plates. A major emphasis was placed on selection of alloy foil composition and nitidation conditions potentially capable of meeting the stringent cost goals for automotive PEMFC applications. Developmental Fe-20Cr-4V alloy and type 2205 stainless steel foils were treated by pre-oxidation and nitridation to form low-ICR, corrosion-resistant surfaces. Promising behavior was observed under simulated aggressive anode- and cathode- side bipolar plate conditions for both materials. Variation in ICR values were observed for treated 2205 foil, with lower (better) values generally observed for the treated Fe-20Cr-4V. This behavior was linked to the nature of the pre-oxidized and nitrided surface structure, which contained through surface layer thickness V-nitride particles in the case of Fe-20Cr-4V but near continuous chromia in the case of 2205 stainless steel. The implications of these findings for stamped bipolar plate foils are discussed.

  6. Pre-oxidized and nitrided stainless steel alloy foil for proton exchange membrane fuel cell bipolar plates: Part 1. Corrosion, interfacial contact resistance, and surface structure

    NASA Astrophysics Data System (ADS)

    Brady, M. P.; Wang, H.; Turner, J. A.; Meyer, H. M.; More, K. L.; Tortorelli, P. F.; McCarthy, B. D.

    Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr 2N, CrN, TiN, V 2N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of scale-up studies to determine the feasibility of extending the nitridation approach to thin 0.1 mm stainless steel alloy foils for proton exchange membrane fuel cell (PEMFC) bipolar plates. Developmental Fe-20Cr-4V alloy and type 2205 stainless steel foils were treated by pre-oxidation and nitridation to form low-ICR, corrosion-resistant surfaces. As-treated Fe-20Cr-4V foil exhibited target (low) ICR values, whereas 2205 foil suffered from run-to-run variation in ICR values, ranging up to 2× the target value. Pre-oxidized and nitrided surface structure examination revealed surface-through-layer-thickness V-nitride particles for the treated Fe-20Cr-4V, but near continuous chromia for treated 2205 stainless steel, which was linked to the variation in ICR values. Promising corrosion resistance was observed under simulated aggressive PEMFC anode- and cathode-side bipolar plate conditions for both materials, although ICR values were observed to increase. The implications of these findings for stamped bipolar plate foils are discussed.

  7. Numerical Simulation and Artificial Neural Network Modeling for Predicting Welding-Induced Distortion in Butt-Welded 304L Stainless Steel Plates

    NASA Astrophysics Data System (ADS)

    Narayanareddy, V. V.; Chandrasekhar, N.; Vasudevan, M.; Muthukumaran, S.; Vasantharaja, P.

    2016-02-01

    In the present study, artificial neural network modeling has been employed for predicting welding-induced angular distortions in autogenous butt-welded 304L stainless steel plates. The input data for the neural network have been obtained from a series of three-dimensional finite element simulations of TIG welding for a wide range of plate dimensions. Thermo-elasto-plastic analysis was carried out for 304L stainless steel plates during autogenous TIG welding employing double ellipsoidal heat source. The simulated thermal cycles were validated by measuring thermal cycles using thermocouples at predetermined positions, and the simulated distortion values were validated by measuring distortion using vertical height gauge for three cases. There was a good agreement between the model predictions and the measured values. Then, a multilayer feed-forward back propagation neural network has been developed using the numerically simulated data. Artificial neural network model developed in the present study predicted the angular distortion accurately.

  8. Sensitization of stainless steel

    NASA Technical Reports Server (NTRS)

    Nagy, James P.

    1990-01-01

    The objective of this experiment is to determine the corrosion rates of 18-8 stainless steels that have been sensitized at various temperatures and to show the application of phase diagrams. The laboratory instructor will assign each student a temperature, ranging from 550 C to 1050 C, to which the sample will be heated. Further details of the experimental procedure are detailed.

  9. Nickel release from stainless steels.

    PubMed

    Haudrechy, P; Mantout, B; Frappaz, A; Rousseau, D; Chabeau, G; Faure, M; Claudy, A

    1997-09-01

    In 1994, a study of nickel release and allergic contact dermatitis from nickel-plated metals and stainless steels was published in this journal. It was shown that low-sulfur stainless steel grades like AISI 304, 316L or 430 (S < or = 0.007%) release less than 0.03 microgram/cm2/week of nickel in acid artificial sweat and elicit no reactions in patients already sensitized to nickel. In contrast, nickel-plated samples release around 100 micrograms/cm2/week of Ni and high-sulfur stainless steel (AISI 303-S approximately 0.3%) releases about 1.5 micrograms/cm2/week in this acid artificial sweat. Applied on patients sensitized to nickel, these metals elicit positive reactions in 96% and 14%, respectively, of the patients. The main conclusion was that low-sulfur stainless steels like AISI 304, 316L or 430, even when containing Ni, should not elicit nickel contact dermatitis, while metals having a mean corrosion resistance like a high-sulfur stainless steel (AISI 303) or nickel-plated steel should be avoided. The determining characteristic was in fact the corrosion resistance in chloride media, which, for stainless steels, is connected, among other factors, to the sulfur content. Thus, a question remained concerning the grades with an intermediate sulfur content, around 0.03%, which were not studied. They are the object of the study presented in this paper. 3 tests were performed: leaching experiments, dimethylglyoxime and HNO3 spot tests, and clinical patch tests; however, only stainless steels were tested: a low-sulfur AISI 304 and AISI 303 as references and 3 grades with a sulfur content around 0.03%: AISI 304L, AISI 304L added with Ca, AISI 304L+Cu. Leaching experiments showed that the 4 non-resulfurised grades released less than 0.5 microgram/cm2/week in acid sweat while the reulfurized AISI 303 released around or more than 0.5 microgram/cm2/week. This is explained by the poorer corrosion resistance of the resulfurized grade. Yet all these grades had the same

  10. A metallurgical examination of fractured stainless-steel ASIF tibial plates.

    PubMed

    Richman, M H; Weltman, J K; Cole, A

    1976-08-01

    Between 1970 and 1973 99 tibial fractures were treated by rigid internal fixation with ASIF plates. The fractures were all regarded as sufficiently stable for exercise without weight bearing, thus needing no additional external support during the healing period. Four of the plates broke late in the healing period, after the onset of weight bearing. These fractures had some degree of delayed union with slight resorption of the bone ends, resulting in cyclical bending of the plate. Examination of 2 of the fractured plates by scanning electron microscopy, electron microprobe analysis and optical metallography revealed that the primary cause of plate fracture was fatigue. There was no evidence that corrosion fatigue or inclusion content were factors leading to plate fracture. PMID:1002271

  11. Photon-stimulated desorption yields from stainless steel and copper-plated beam tubes with various pretreatments

    SciTech Connect

    Foerster, C.L.; Halama, H.; Lanni, C. )

    1990-05-01

    Photon-stimulated desorption (PSD) from the walls of electron storage rings and associated beamlines imposes serious limits on their beam quality and beam lifetimes. Stainless steel (SS) is the most used material for beam lines and its use has become more dominant for dedicated light sources. Copper-plated SS beam pipes have been selected for the superconducting super collider (SSC) project. Three-meter-long tubes of 3, 8.8, and 10 cm diameter were prepared using the following pretreatments common in storage rings. The samples were chemically cleaned only, vacuum baked to 200 {degree}C, vacuum fired to 950 {degree}C, and argon--oxygen glow-discharge conditioned. A dedicated beam line at the National Synchrotron Light Source was used to measure PSD from the samples. Desorption was measured as a function of beam current during exposure to white light having a critical energy of 500 MeV. Our results are presented and compared with PSD from previous work on aluminum and SS here and at other laboratories. Glow-discharged SS yields the lowest PSD.

  12. Probing Formability Improvement of Ultra-thin Ferritic Stainless Steel Bipolar Plate of PEMFC in Non-conventional Forming Process

    NASA Astrophysics Data System (ADS)

    Bong, Hyuk Jong; Barlat, Frédéric; Lee, Myoung-Gyu

    2016-08-01

    Formability increase in non-conventional forming profiles programmed in the servo-press was investigated using finite element analysis. As an application, forming experiment on a 0.15-mm-thick ferritic stainless steel sheet for a bipolar plate, a primary component of a proton exchange membrane fuel cell, was conducted. Four different forming profiles were considered to investigate the effects of forming profiles on formability and shape accuracy. The four motions included conventional V motion, holding motion, W motion, and oscillating motion. Among the four motions, the holding motion, in which the slide was held for a certain period at the bottom dead point, led to the best formability. Finite element simulations were conducted to validate the experimental results and to probe the formability improvement in the non-conventional forming profiles. A creep model to address stress relaxation effect along with tool elastic recovery was implemented using a user-material subroutine, CREEP in ABAQUS finite element software. The stress relaxation and variable contact conditions during the holding and oscillating profiles were found to be the main mechanism of formability improvement.

  13. Probing Formability Improvement of Ultra-thin Ferritic Stainless Steel Bipolar Plate of PEMFC in Non-conventional Forming Process

    NASA Astrophysics Data System (ADS)

    Bong, Hyuk Jong; Barlat, Frédéric; Lee, Myoung-Gyu

    2016-05-01

    Formability increase in non-conventional forming profiles programmed in the servo-press was investigated using finite element analysis. As an application, forming experiment on a 0.15-mm-thick ferritic stainless steel sheet for a bipolar plate, a primary component of a proton exchange membrane fuel cell, was conducted. Four different forming profiles were considered to investigate the effects of forming profiles on formability and shape accuracy. The four motions included conventional V motion, holding motion, W motion, and oscillating motion. Among the four motions, the holding motion, in which the slide was held for a certain period at the bottom dead point, led to the best formability. Finite element simulations were conducted to validate the experimental results and to probe the formability improvement in the non-conventional forming profiles. A creep model to address stress relaxation effect along with tool elastic recovery was implemented using a user-material subroutine, CREEP in ABAQUS finite element software. The stress relaxation and variable contact conditions during the holding and oscillating profiles were found to be the main mechanism of formability improvement.

  14. Nickel: makes stainless steel strong

    USGS Publications Warehouse

    Boland, Maeve A.

    2012-01-01

    Nickel is a silvery-white metal that is used mainly to make stainless steel and other alloys stronger and better able to withstand extreme temperatures and corrosive environments. Nickel was first identified as a unique element in 1751 by Baron Axel Fredrik Cronstedt, a Swedish mineralogist and chemist. He originally called the element kupfernickel because it was found in rock that looked like copper (kupfer) ore and because miners thought that "bad spirits" (nickel) in the rock were making it difficult for them to extract copper from it. Approximately 80 percent of the primary (not recycled) nickel consumed in the United States in 2011 was used in alloys, such as stainless steel and superalloys. Because nickel increases an alloy's resistance to corrosion and its ability to withstand extreme temperatures, equipment and parts made of nickel-bearing alloys are often used in harsh environments, such as those in chemical plants, petroleum refineries, jet engines, power generation facilities, and offshore installations. Medical equipment, cookware, and cutlery are often made of stainless steel because it is easy to clean and sterilize. All U.S. circulating coins except the penny are made of alloys that contain nickel. Nickel alloys are increasingly being used in making rechargeable batteries for portable computers, power tools, and hybrid and electric vehicles. Nickel is also plated onto such items as bathroom fixtures to reduce corrosion and provide an attractive finish.

  15. Electroless Plating of Palladium on Stainless Steel Substrates in Hydrazine Solutions: A Study of the Relationships Between Bath Parameters, Deposition Mechanisms, and Deposit Morphologies

    NASA Astrophysics Data System (ADS)

    Davis, Stacy

    Development of a reliable and inexpensive method for producing hydrogen permeable membranes is of intense interest to ongoing fuel cell research. This study investigated electroless plating of palladium onto stainless steel substrates in hydrazine solution as a possible means of membrane production. Following initial research to establish the optimum infiltrant particle size, sensitization time, and activation time, electroless plating experiments were performed to determine the effects of varying hydrazine concentration, agitation, and residence time on the palladium deposit quality and morphology. SEM examination of the experimental products elucidated relationships between specific plating bath parameters or combinations of parameters, the governing deposition mechanisms, and the deposit morphologies. The results indicate that it is possible to produce application-specific deposit layer morphologies by modifying the plating bath parameters at critical stages of the plating cycle.

  16. Stainless steel recycle FY94 progress report

    SciTech Connect

    Imrich, K.J.

    1994-10-28

    The Materials Technology Section (MTS) of the Savannah River Technology Center (SRTC) was asked to demonstrate the practicality of recycling previously contaminated stainless steel components such as reactor heat exchanger heads, process water piping and slug buckets into 208 liters (55 gallon) drums and 2.8 cubic meter (100 ft{sup 3}) storage boxes. Radioactively contaminated stainless steel scrap will be sent to several industrial partners where it will be melted, decontaminated/cast into ingots, and rolled into plate and sheet and fabricated into the drums and boxes. As part of this recycle initiative, MTS was requested to demonstrate that radioactively contaminated Type 304L stainless steel could be remelted and cast to meet the applicable ASTM specification for fabrication of drums and boxes. In addition, MTS was requested to develop the technical basis of melt decontamination and establish practicality of using this approach for value added products. The findings presented in this investigation lead to the following conclusions: recycle of 18 wt% Cr-8 wt% Ni alloy can be achieved by melting Type 304 stainless steel in a air vacuum induction furnace; limited melt decontamination of the contaminated stainless steel was achieved, surface contamination was removed by standard decontamination techniques; carbon uptake in the as-cast ingots resulted from the graphite susceptor used in this experiment and is unavoidable with this furnace configuration. A new furnace optimized for melting stainless steel has been installed and is currently being tested for use in this program.

  17. Photodesorption from stainless steels

    NASA Technical Reports Server (NTRS)

    Mesarwi, A.; Ignatiev, A.

    1988-01-01

    The photodesorption by low-energy photons from three types of stainless steels is examined. For all these systems both CO and CO2 were observed to photodesorb with high yields: about 0.001 molecules/photon for CO2 and about 0.0001 molecules/photon for CO at 250 nm. The observed threshold energies were found to be the same for all systems at E0 = 2.92 eV for CO2 and E0 = 2.92-3.10 eV for CO.

  18. Austenitic stainless steels for cryogenic service

    SciTech Connect

    Dalder, E.N.C.; Juhas, M.C.

    1985-09-19

    Presently available information on austenitic Fe-Cr-Ni stainless steel plate, welds, and castings for service below 77 K are reviewed with the intent (1) of developing systematic relationships between mechanical properties, composition, microstructure, and processing, and (2) of assessing the adequacy of these data bases in the design, fabrication, and operation of engineering systems at 4 K.

  19. Switch to duplex stainless steels

    SciTech Connect

    Quik, J.M.A.; Geudeke, M.

    1994-11-01

    Duplex stainless steels contain approximately equal proportions of ferrite and austenite. These stainless steels have become an established material of construction in the chemical process industries (CPI). Duplexes offer benefits over austenitic stainless steels and carbon steels because of their higher strength, and good toughness and ductility, in combination with equivalent resistance to general corrosion, as well as better resistance to localized corrosion and stress corrosion cracking. Additionally, duplex materials have thermal-conductivity and thermal-expansion coefficients similar to those of ferritic materials, are tough at low (sub-zero) temperatures, and have a high resistance to erosion and abrasion. In some of the highly corrosive environments encountered in the CPI, the super duplex stainless steels offer cost-effective options not possible with the standard austenitic stainless steels. The initial applications were almost exclusively as heat exchanger tubing in water-cooled service. In recent times, duplex stainless steels have been used in the oil, gas, and chemical industries. Examples include service in sweet and mildly sour corrosive environments, on offshore platforms where weight savings can be realized, and as a replacement for standard austenitic stainless steel in chemical-processing plants.

  20. Improved anticorrosion properties and electrical conductivity of 316L stainless steel as bipolar plate for proton exchange membrane fuel cell by lower temperature chromizing treatment

    NASA Astrophysics Data System (ADS)

    Yang, Lijun; Yu, Haijun; Jiang, Lijun; Zhu, Lei; Jian, Xuyu; Wang, Zhong

    The lower temperature chromizing treatment is developed to modify 316L stainless steel (SS 316L) for the application of bipolar plate in proton exchange membrane fuel cell (PEMFC). The treatment is performed to produce a coating, containing mainly Cr-carbide and Cr-nitride, on the substrate to improve the anticorrosion properties and electrical conductivity between the bipolar plate and carbon paper. Shot peening is used as the pretreatment to produce an activated surface on stainless steel to reduce chromizing temperature. Anticorrosion properties and interfacial contact resistance (ICR) are investigated in this study. Results show that the chromized SS 316L exhibits better corrosion resistance and lower ICR value than those of bare SS 316L. The chromized SS 316L shows the passive current density about 3E-7 A cm -2 that is about four orders of magnitude lower than that of bare SS 316L. ICR value of the chromized SS 316L is 13 mΩ cm 2 that is about one-third of bare SS 316L at 200 N cm -2 compaction forces. Therefore, this study clearly states the performance advantages of using chromized SS 316L by lower temperature chromizing treatment as bipolar plate for PEMFC.

  1. Effects of Mo content on microstructure and corrosion resistance of arc ion plated Ti-Mo-N films on 316L stainless steel as bipolar plates for polymer exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Kim, Kwang Ho; Shao, Zhigang; Wang, Feifei; Zhao, Shuang; Suo, Ni

    2014-05-01

    Bipolar plates are one of the most important components in PEMFC stack and have multiple functions, such as separators and current collectors, distributing reactions uniformly, and etc. Stainless steel is ideal candidate for bipolar plates owing to good thermal and electrical conductivity, good mechanical properties etc. However, stainless steel plate still cannot resist the corrosion of working condition. In this work, ternary Ti-Mo-N film was fabricated on 316L stainless steel (SS316L) as a surface modification layer to enhance the corrosion resistance. Effects of Mo content on the microstructure and corrosion resistance of Ti-Mo-N films are systematically investigated by altering sputtering current of the Mo target. XRD results reveal that the preferred orientation changes from [111] to [220] direction as Mo content in the film increases. The synthesized Ti-Mo-N films form a substitutional solid solution of (Ti, Mo)N where larger Mo atoms replace Ti in TiN crystal lattice. The TiN-coated SS316L sample shows the best corrosion resistance. While Mo content in the Ti-Mo-N films increases, the corrosion resistance gradually degrades. Compared with the uncoated samples, all the Ti-Mo-N film coated samples show enhanced corrosion resistance in simulated PEMFC working condition.

  2. Stainless Steel Microstructure and Mechanical Properties Evaluation

    SciTech Connect

    Switzner, Nathan T

    2010-06-01

    A nitrogen strengthened 21-6-9 stainless steel plate was spinformed into hemispherical test shapes. A battery of laboratory tests was used to characterize the hemispheres. The laboratory tests show that near the pole (axis) of a spinformed hemisphere the yield strength is the lowest because this area endures the least “cold-work” strengthening, i.e., the least deformation. The characterization indicated that stress-relief annealing spinformed stainless steel hemispheres does not degrade mechanical properties. Stress-relief annealing reduces residual stresses while maintaining relatively high mechanical properties. Full annealing completely eliminates residual stresses, but reduces yield strength by about 30%.

  3. DETECTION OF BACTERIAL BIOFILM ON STAINLESS STEEL BY HYPERSPECTRAL FLUORESCENCE IMAGING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, hyperspectral fluorescence imaging techniques were investigated for detection of microbial biofilm on stainless steel plates typically used to manufacture food processing equipment. Stainless steel coupons were immersed in bacterium cultures consisting of nonpathogenic E. coli, Pseudo...

  4. Corrosion resistance of stainless steels

    SciTech Connect

    Dillon, C.P.

    1995-12-31

    This book reviews the mechanisms and forms of corrosion and examines the corrosion of stainless steels and similar chromium-bearing nickel containing higher alloys, detailing various corrosive environments including atmospheric and fire-side corrosion, corrosion by water and soil, and corrosion caused by particular industrial processes. It provides information on specific groups and grades of stainless steels; summarizes typical applications for specific stainless alloys; describes common corrosion problems associated with stainless steels; presents the acceptable isocorrosion parameters of concentration and temperature for over 250 chemicals for which stainless steels are the preferred materials of construction; discusses product forms and their availability; elucidates fabrication, welding, and joining techniques; and covers the effects of pickling and passivation.

  5. Stainless Steel Permeability

    SciTech Connect

    Buchenauer, Dean A.; Karnesky, Richard A.

    2015-09-01

    An understanding of the behavior of hydrogen isotopes in materials is critical to predicting tritium transport in structural metals (at high pressure), estimating tritium losses during production (fission environment), and predicting in-vessel inventory for future fusion devices (plasma driven permeation). Current models often assume equilibrium diffusivity and solubility for a class of materials (e.g. stainless steels or aluminum alloys), neglecting trapping effects or, at best, considering a single population of trapping sites. Permeation and trapping studies of the particular castings and forgings enable greater confidence and reduced margins in the models. For FY15, we have continued our investigation of the role of ferrite in permeation for steels of interest to GTS, through measurements of the duplex steel 2507. We also initiated an investigation of the permeability in work hardened materials, to follow up on earlier observations of unusual permeability in a particular region of 304L forgings. Samples were prepared and characterized for ferrite content and coated with palladium to prevent oxidation. Issues with the poor reproducibility of measurements at low permeability were overcome, although the techniques in use are tedious. Funding through TPBAR and GTS were secured for a research grade quadrupole mass spectrometer (QMS) and replacement turbo pumps, which should improve the fidelity and throughput of measurements in FY16.

  6. Ultrasonic Spectroscopy of Stainless Steel Sandwich Panels

    NASA Technical Reports Server (NTRS)

    Cosgriff, Laura M.; Lerch, Bradley A.; Hebsur, Mohan G.; Baaklini, George Y.; Ghosn, Louis J.

    2003-01-01

    Enhanced, lightweight material systems, such as 17-4PH stainless steel sandwich panels are being developed for use as fan blades and fan containment material systems for next generation engines. In order to improve the production for these systems, nondestructive evaluation (NDE) techniques, such as ultrasonic spectroscopy, are being utilized to evaluate the brazing quality between the 17-4PH stainless steel face plates and the 17-4PH stainless steel foam core. Based on NDE data, shear tests are performed on sections representing various levels of brazing quality from an initial batch of these sandwich structures. Metallographic characterization of brazing is done to corroborate NDE findings and the observed shear failure mechanisms.

  7. Explosive Surface Hardening of Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Kovacs-Coskun, T.

    2016-04-01

    In this study, the effects of explosion hardening on the microstructure and the hardness of austenitic stainless steel have been studied. The optimum explosion hardening technology of austenitic stainless steel was researched. In case of the explosive hardening used new idea mean indirect hardening setup. Austenitic stainless steels have high plasticity and can be easily cold formed. However, during cold processing the hardening phenomena always occurs. Upon the explosion impact, the deformation mechanism indicates a plastic deformation and this deformation induces a phase transformation (martensite). The explosion hardening enhances the mechanical properties of the material, includes the wear resistance and hardness. In case of indirect hardening as function of the setup parameters specifically the flayer plate position the hardening increased differently. It was find a relationship between the explosion hardening setup and the hardening level.

  8. Stainless steel display evaluation

    NASA Astrophysics Data System (ADS)

    Hopper, Darrel G.; Meyer, Frederick M.; Longo, Sam J.; Trissell, Terry L.

    2007-04-01

    Active matrix organic light emitting diode (AMOLED) technology is one candidate to become a low power alternative in some applications to the currently dominant, active matrix liquid crystal display (AMLCD), technology. Furthermore, fabrication of the AMOLED on stainless steel (SS) foil rather than the traditional glass substrate, while presenting a set of severe technical challenges, opens up the potential for displays that are both lighter and less breakable. Also, transition to an SS foil substrate may enable rollable displays - large when used but small for stowage within gear already worn or carried or installed. Research has been initiated on AMOLED/SS technology and the first 320 x 240 color pixel 4-in. demonstration device has been evaluated in the AFRL Display Test and Evaluation Laboratory. Results of this evaluation are reported along with a research roadmap.

  9. Welding tritium exposed stainless steel

    SciTech Connect

    Kanne, W.R. Jr.

    1994-11-01

    Stainless steels that are exposed to tritium become unweldable by conventional methods due to buildup of decay helium within the metal matrix. With longer service lives expected for tritium containment systems, methods for welding on tritium exposed material will become important for repair or modification of the systems. Solid-state resistance welding and low-penetration overlay welding have been shown to mitigate helium embrittlement cracking in tritium exposed 304 stainless steel. These processes can also be used on stainless steel containing helium from neutron irradiation, such as occurs in nuclear reactors.

  10. An investigation of the typical corrosion parameters used to test polymer electrolyte fuel cell bipolar plate coatings, with titanium nitride coated stainless steel as a case study

    NASA Astrophysics Data System (ADS)

    Orsi, A.; Kongstein, O. E.; Hamilton, P. J.; Oedegaard, A.; Svenum, I. H.; Cooke, K.

    2015-07-01

    Stainless steel bipolar plates (BPP) for polymer electrolyte membrane fuel cells (PEMFCs) have good manufacturability, durability and low costs, but inadequate corrosion resistance and elevated interfacial contact resistance (ICR) in the fuel cell environment. Thin film coatings of titanium nitride (TiN) of 1 μm in thickness, were deposited by means of physical vapour deposition (PVD) process on to stainless steel (SS) 316L substrates and were evaluated, in a series of tests, for their level of corrosion protection and ICR. In the ex-situ corrosion tests, variables such as applied potential, experimental duration and pH of the sulphate electrolyte at 80 °C were altered. The ICR values were found to increase after exposure to greater applied potentials and electrolytes of a higher pH. In terms of experimental duration, the ICR increased most rapidly at the beginning of each experiment. It was also found that the oxidation of TiN was accelerated after exposure to electrolytes of a higher pH. When coated BPPs were incorporated into an accelerated fuel cell test, the degradation of the fuel cell cathode resembled the plates that were tested at the highest anodic potential (1.4 VSHE).

  11. Why stainless steel corrodes.

    PubMed

    Ryan, Mary P; Williams, David E; Chater, Richard J; Hutton, Bernie M; McPhail, David S

    2002-02-14

    Stainless steels are used in countless diverse applications for their corrosion resistance. Although they have extremely good general resistance, they are nevertheless susceptible to pitting corrosion. This localized dissolution of an oxide-covered metal in specific aggressive environments is one of the most common and catastrophic causes of failure of metallic structures. The pitting process has been described as random, sporadic and stochastic and the prediction of the time and location of events remains extremely difficult. Many contested models of pitting corrosion exist, but one undisputed aspect is that manganese sulphide inclusions play a critical role. Indeed, the vast majority of pitting events are found to occur at, or adjacent to, such second-phase particles. Chemical changes in and around sulphide inclusions have been postulated as a mechanism for pit initiation but such variations have never been measured. Here we use nanometre-scale secondary ion mass spectroscopy to demonstrate a significant reduction in the Cr:Fe ratio of the steel matrix around MnS particles. These chromium-depleted zones are susceptible to high-rate dissolution that 'triggers' pitting. The implications of these results are that materials processing conditions control the likelihood of corrosion failures, and these data provide a basis for optimizing such conditions. PMID:11845203

  12. Manufacturing and Performance Assessment of Stamped, Laser Welded, and Nitrided FeCrV Stainless Steel Bipolar Plates for Proton Exchange Membrane Fuel Cells

    SciTech Connect

    Brady, Michael P; Abdelhamid, Mahmoud; Dadheech, G; Bradley, J; Toops, Todd J; Meyer III, Harry M; Tortorelli, Peter F

    2013-01-01

    A manufacturing and single-cell fuel cell performance study of stamped, laser welded, and gas nitrided ferritic stainless steel foils in an advanced automotive bipolar plate assembly design was performed. Two developmental foil compositions were studied: Fee20Cre4V and Fee23Cre4V wt.%. Foils 0.1 mm thick were stamped and then laser welded together to create single bipolar plate assemblies with cooling channels. The plates were then surface treated by pre-oxidation and nitridation in N2e4H2 based gas mixtures using either a conventional furnace or a short-cycle quartz lamp infrared heating system. Single-cell fuel cell testing was performed at 80 C for 500 h at 0.3 A/cm2 using 100% humidification and a 100%/40% humidification cycle that stresses the membrane and enhances release of the fluoride ion and promotes a more corrosive environment for the bipolar plates. Periodic high frequency resistance potential-current scans during the 500 h fuel cell test and posttest analysis of the membrane indicated no resistance increase of the plates and only trace levels of metal ion contamination.

  13. Standard specification for heat-resisting chromium and chromium-nickel stainless steel plate, sheet, and strip for pressure vessels. ASTM standard

    SciTech Connect

    1998-10-01

    This specification is under the jurisdiction of ASTM Committee A-1 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.17 on Flat Stainless Steel Products. Current edition approved Sep. 10, and Nov. 10, 1997, Apr. 10, and Jun. 10, 1998. Published October 1998. Originally published as A 240-40T. Last previous edition A 240/A 240M-97a.

  14. Multilayered Zr-C/a-C film on stainless steel 316L as bipolar plates for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Bi, Feifei; Peng, Linfa; Yi, Peiyun; Lai, Xinmin

    2016-05-01

    A multilayered zirconium-carbon/amorphous carbon (Zr-C/a-C) coating is synthesized by magnetron sputtering in order to improve the corrosion resistance and interfacial conductivity of stainless steel 316L (SS316L) as bipolar plates for proton exchange membrane fuel cells (PEMFCs). Zr-C/a-C film contains an outmost pure amorphous carbon layer and a sub zirconium containing carbon layer. Interfacial contact resistance (ICR) between carbon paper and coated SS316L decreases to 3.63 mΩ cm2 at 1.4 MPa. Potentiodynamic polarization results reveal that the corrosion potential of Zr-C/a-C coated sample is more positive than pure a-C coated sample and the current density is only 0.49 μA cm-2 at the cathode applied potential 0.6 V. Electrochemical impendence spectroscopy also indicates that multilayered Zr-C/a-C film coated SS316L has much higher charge transfer resistance than the bare sample. After potentiostatic polarization, ICR values are 3.92 mΩ cm2 and 3.82 mΩ cm2 in the simulated PEMFCs cathode and anode environment, respectively. Moreover, XPS analysis of the coated samples before and after potential holding tests shows little difference, which disclose the chemical stability of multilayered Zr-C/a-C film. Therefore, the multilayered Zr-C/a-C coating exhibits excellent performance in various aspects and is preferred for the application of stainless steel bipolar plates.

  15. Corrosion behaviour of austenitic stainless steel as a function of methanol concentration for direct methanol fuel cell bipolar plate

    NASA Astrophysics Data System (ADS)

    Wang, Lixia; Kang, Bin; Gao, Na; Du, Xiao; Jia, Linan; Sun, Juncai

    2014-05-01

    The corrosion behaviour of an AISI 304 stainless steel (304 SS) is investigated in aqueous acid methanol solutions (0.5 M H2SO4 + 2 ppm HF + x M CH3OH, x = 0, 1, 5, 10 and 20) at 50 °C to simulate the varied anodic operating conditions of direct methanol fuel cells. Electrochemical measurements including potentiodynamic polarisation, potentiostatic polarisation and electrochemical impedance spectroscopy tests, are employed to analyse the corrosion behaviour. The results reveal that the corrosion resistance of 304 SS is enhanced in solutions with higher methanol content. Scanning electron microscopy and inductively coupled plasma atomic emission spectrometry data indicate that the surface corrosion on 304 SS is alleviated when the methanol concentration is increased. According to the X-ray photoelectron spectroscopy and Mott-Schottky analyses, the passive films formed on the 304 SS after potentiostatic tests in all the test solutions are composed of a duplex electronic structure with an external n-type semiconductor layer and an internal p-type semiconductor layer. Further analyses of the surface conductivity conducted by measuring the interfacial contact resistance between the 304 SS and carbon paper reveal that the passive film formed in the solution with higher methanol content exhibits lower conductivity.

  16. Corrosion behavior of 2205 duplex stainless steel.

    PubMed

    Platt, J A; Guzman, A; Zuccari, A; Thornburg, D W; Rhodes, B F; Oshida, Y; Moore, B K

    1997-07-01

    The corrosion of 2205 duplex stainless steel was compared with that of AISI type 316L stainless steel. The 2205 stainless steel is a potential orthodontic bracket material with low nickel content (4 to 6 wt%), whereas the 316L stainless steel (nickel content: 10 to 14 wt%) is a currently used bracket material. Both stainless steels were subjected to electrochemical and immersion (crevice) corrosion tests in 37 degrees C, 0.9 wt% sodium chloride solution. Electrochemical testing indicates that 2205 has a longer passivation range than 316L. The corrosion rate of 2205 was 0.416 MPY (milli-inch per year), whereas 316L exhibited 0.647 MPY. When 2205 was coupled to 316L with equal surface area ratio, the corrosion rate of 2205 reduced to 0.260 MPY, indicating that 316L stainless steel behaved like a sacrificial anode. When 316L is coupled with NiTi, TMA, or stainless steel arch wire and was subjected to the immersion corrosion test, it was found that 316L suffered from crevice corrosion. On the other hand, 2205 stainless steel did not show any localized crevice corrosion, although the surface of 2205 was covered with corrosion products, formed when coupled to NiTi and stainless steel wires. This study indicates that considering corrosion resistance, 2205 duplex stainless steel is an improved alternative to 316L for orthodontic bracket fabrication when used in conjunction with titanium, its alloys, or stainless steel arch wires. PMID:9228844

  17. Annealing induced interfacial layers in niobium-clad stainless steel developed as a bipolar plate material for polymer electrolyte membrane fuel cell stacks

    SciTech Connect

    Hong, Sung Tae; Weil, K. Scott; Choi, Jung-Pyung; Bae, In-Tae; Pan, Jwo

    2010-05-01

    Niobium (Nb)-clad 304L stainless steel (SS) manufactured by cold rolling is currently under consideration for use as a bipolar plate material in polymer electrolyte membrane fuel cell (PEMFC) stacks. To make the fabrication of bipolar plates using the Nb-clad SS feasible, annealing may be necessary for the Nb-clad SS to reduce the springback induced by cold rolling. However, the annealing can develop an interfacial layer between the Nb cladding and the SS core and the interfacial layer plays a key role in the failure of the Nb-clad SS as reported earlier [JPS our work]. In this investigation, the Nb-clad SS specimens in as-rolled condition were annealed at different combinations of temperature and time. Based on the results of scanning electron microscope (SEM) analysis, an annealing process map for the Nb-clad SS was obtained. The results of SEM analysis and Transmission Electron Microscope (TEM) analysis also suggest that different interfacial layers occurred based on the given annealing conditions.

  18. Electrochemical behavior of nanocrystalline Ta/TaN multilayer on 316L stainless steel: Novel bipolar plates for proton exchange membrane fuel-cells

    NASA Astrophysics Data System (ADS)

    Alishahi, M.; Mahboubi, F.; Mousavi Khoie, S. M.; Aparicio, M.; Hübner, R.; Soldera, F.; Gago, R.

    2016-08-01

    Insufficient corrosion resistance and surface conductivity are two main issues that plague large-scale application of stainless steel (SS) bipolar plates in proton exchange membrane fuel cells (PEMFCs). This study explores the use of nanocrystalline Ta/TaN multilayer coatings to improve the electrical and electrochemical performance of polished 316L SS bipolar plates. The multilayer coatings have been deposited by (reactive) magnetron sputtering and characterized by X-ray diffraction, field-emission scanning electron microscopy and transmission electron microscopy. The electrochemical behavior of bare and coated substrates has been evaluated in simulated PEMFC working environments by potentiodynamic and potentiostatic polarization tests at ambient temperature and 80 °C. The results show that the Ta/TaN multilayer coating increases the polarization resistance of 316L SS by about 30 and 104 times at ambient and elevated temperatures, respectively. The interfacial contact resistance (ICR) shows a low value of 12 mΩ × cm2 before the potentiostatic test. This ICR is significantly lower than for the bare substrate and remains mostly unchanged after potentiostatic polarization for 14 h. In addition, the high contact angle (92°) with water for coated substrates indicates a hydrophobic character, which can improve the water management within the cell in PEMFC stacks.

  19. Microbial corrosion of stainless steel.

    PubMed

    Ibars, J R; Moreno, D A; Ranninger, C

    1992-11-01

    Stainless steel, developed because of their greater resistance to corrosion in different aggressive environments, have proved to be affected, however, by various processes and types of corrosion. Some of these types of corrosion, mainly pitting, is activated and developed in the presence of microorganisms, which acting in an isolated or symbiotic way, according to their adaptation to the environment, create a favorable situation for the corrosion of these steel. The microorganisms that are involved, mainly bacteria of both the aerobic and anaerobic type, modify the environment where the stainless steel is found, creating crevices, differential aeration zones or a more aggressive environment with the presence of metabolites. In these circumstances, a local break of the passive and passivating layer is produced, which is proper to these types of steel and impedes the repassivation that is more favorable to corrosion. In the study and research of these types of microbiologically influenced corrosion are found electrochemical techniques, since corrosion is fundamentally an electrochemical process, and microbiological techniques for the identification, culture, and evaluation of the microorganisms involved in the process, as well as in the laboratory or field study of microorganism-metal pairs. Microstructural characterization studies of stainless steel have also been considered important, since it is known that the microstructure of steel can substantially modify their behavior when faced with corrosion. As for surface analysis studies, it is known that corrosion is a process that is generated on and progresses from the surface. The ways of dealing with microbiologically influenced corrosion must necessarily include biocides, which are not always usable or successful, the design of industrial equipment or components that do not favor the adherence of microorganisms, using microstructures in steel less sensitive to corrosion, or protecting the materials. PMID:1492953

  20. Development of New Stainless Steel

    SciTech Connect

    Robert F. Buck

    2005-08-30

    A new family of innovative martensitic stainless steels, 521-A, 521-B, and 521-C has been developed by Advanced Steel Technology, LLC (Trafford, PA) as high strength fastener (bolt) materials for use at moderate temperatures in turbine engines, including steam turbines, gas turbines, and aircraft engines. The primary objective of the development program was to create a martensitic stainless steel with high strength at moderate temperatures, and which could replace the expensive nickel-based superalloy IN 718 in some fasteners applications. A secondary objective was to replace conventional 12Cr steels such as AISI 422 used as blades, buckets and shafts that operate at intermediate temperatures in turbine engines with stronger steel. The composition of the new alloys was specifically designed to produce excellent mechanical properties while integrating heat treatment steps into production to reduce energy consumption during manufacturing. As a result, production costs and energy consumption during production of rolled bar products is significantly lower than conventional materials. Successful commercialization of the new alloys would permit the installed cost of certain turbine engines to be reduced without sacrificing high availability or operational flexibility, thereby enhancing the global competitiveness of U.S. turbine engine manufacturers. Moreover, the domestic specialty steel industry would also benefit through increased productivity and reduced operating costs, while increasing their share of the international market for turbine engine fasteners, blades, buckets and shafts.

  1. Compressive Strength of Stainless-Steel Sandwiches at Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Mathauser, Eldon E.; Pride, Richard A.

    1959-01-01

    Experimental results are presented from crippling tests of stainless-steel sandwich specimens in the temperature range from 80 F to 1,200 F. The specimens included resistance-welded 17-7 PH stainless-steel sandwiches with single-corrugated cores, type 301 stainless-steel sandwiches with double-corrugated cores, and brazed 17-7 PH stainless-steel sandwiches with honeycomb cores. The experimental strengths are compared with predicted buckling and crippling strengths. The crippling strengths were predicted from the calculated maximum strength of the individual plate elements of the sandwiches and from a correlation procedure which gives the elevated-temperature crippling strength when the experimental room-temperature crippling strengths are known. Photographs of some of the tested specimens are included to show the modes of failure.

  2. Nano-composite stainless steel

    DOEpatents

    Dehoff, Ryan R.; Blue, Craig A.; Peter, William H.; Chen, Wei; Aprigliano, Louis F.

    2015-07-14

    A composite stainless steel composition is composed essentially of, in terms of wt. % ranges: 25 to 28 Cr; 11 to 13 Ni; 7 to 8 W; 3.5 to 4 Mo; 3 to 3.5 B; 2 to 2.5 Mn; 1 to 1.5 Si; 0.3 to 1.7 C; up to 2 O; balance Fe. The composition has an austenitic matrix phase and a particulate, crystalline dispersed phase.

  3. From flint to stainless steel: observations on surgical instrument composition.

    PubMed Central

    Kirkup, J.

    1993-01-01

    Man's failure to extract deeply embedded thorns and arrowheads, with bare hands and teeth, stimulated 'instrument substitutes' mimicking these appendages. Evidence from primitive communities suggest animal, plant and mineral items were employed, both before and after metal became the standard material of today's armamentarium. Changing surgical instrument composition has mirrored concurrent technology and manufacturing methods both of which are reviewed. Particular significance is accorded flint, bronze, crucible steel, thermal sterilisation, nickel-plate, stainless steel and disposable plastics. The paper is based on an exhibition From Flint to Stainless Steel on display at the College. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:8215156

  4. Fatigue Crack Growth Behavior of Gas Metal Arc Welded AISI 409 Grade Ferritic Stainless Steel Joints

    NASA Astrophysics Data System (ADS)

    Lakshminarayanan, A. K.; Shanmugam, K.; Balasubramanian, V.

    2009-10-01

    The effect of filler metals such as austenitic stainless steel, ferritic stainless steel, and duplex stainless steel on fatigue crack growth behavior of the gas metal arc welded ferritic stainless steel joints was investigated. Rolled plates of 4 mm thickness were used as the base material for preparing single ‘V’ butt welded joints. Center cracked tensile specimens were prepared to evaluate fatigue crack growth behavior. Servo hydraulic controlled fatigue testing machine with a capacity of 100 kN was used to evaluate the fatigue crack growth behavior of the welded joints. From this investigation, it was found that the joints fabricated by duplex stainless steel filler metal showed superior fatigue crack growth resistance compared to the joints fabricated by austenitic and ferritic stainless steel filler metals. Higher yield strength and relatively higher toughness may be the reasons for superior fatigue performance of the joints fabricated by duplex stainless steel filler metal.

  5. 60 Years of duplex stainless steel applications

    SciTech Connect

    Olsson, J.; Liljas, M.

    1994-12-31

    In this paper the history of wrought duplex stainless steel development and applications is described. Ferritic-austenitic stainless steels were introduced only a few decades after stainless steels were developed. The paper gives details from the first duplex stainless steels in the 1930`s to the super duplex stainless steel development during the 1980`s. During the years much effort has been devoted to production and welding metallurgy as well as corrosion research of the duplex stainless steels. Therefore, duplex stainless steels are to-day established in a wide product range. Numerous important applications are exemplified. In most cases the selection of a duplex steel has been a result of the combination high strength excellent corrosion resistance. In the pulp and paper industry the most interesting use is as vessel material in digesters. For chemical process industry, the duplex steels are currently used in heat exchangers. The largest application of duplex steels exists in the oil and gas/offshore industry. Hundreds of kms of pipelines are installed and are still being installed. An increased use of duplex steels is foreseen in areas where the strength is of prime importance.

  6. High-temperature brazing of stainless steel

    NASA Technical Reports Server (NTRS)

    Beuyukian, C. S.; Heisman, R. M.; Mitchell, M. J.

    1978-01-01

    Prevention of iron contamination of platens is eliminated by placing alumina/silica ceramic-fiber blankets between platens and carbon-steel plate. Carbon-steel plates provide rigidity and improve heat transfer.

  7. METHOD FOR JOINING ALUMINUM TO STAINLESS STEEL

    DOEpatents

    Lemon, L.C.

    1960-05-24

    Aluminum may be joined to stainless steel without the use of flux by tinning the aluminum with a tin solder containing 1% silver and 1% lead, tinning the stainless steel with a 50% lead 50% tin solder, and then sweating the tinned surfaces together.

  8. Interaction between stainless steel and plutonium metal

    SciTech Connect

    Dunwoody, John T; Mason, Richard E; Freibert, Franz J; Willson, Stephen P; Veirs, Douglas K; Worl, Laura A; Archuleta, Alonso; Conger, Donald J

    2010-01-01

    Long-term storage of excess plutonium is of great concern in the U.S. as well as abroad. The current accepted configuration involves intimate contact between the stored material and an iron-bearing container such as stainless steel. While many safety scenario studies have been conducted and used in the acceptance of stainless steel containers, little information is available on the physical interaction at elevated temperatures between certain forms of stored material and the container itself. The bulk of the safety studies has focused on the ability of a package to keep the primary stainless steel containment below the plutonium-iron eutectic temperature of approximately 410 C. However, the interactions of plutonium metal with stainless steel have been of continuing interest. This paper reports on a scoping study investigating the interaction between stainless steel and plutonium metal in a pseudo diffusion couple at temperatures above the eutectic melt-point.

  9. The comparison of frictional resistance in titanium, self-ligating stainless steel, and stainless steel brackets using stainless steel and TMA archwires: An in vitro study

    PubMed Central

    Khalid, Syed Altaf; Kumar, Vadivel; Jayaram, Prithviraj

    2012-01-01

    Aim: The aim of the study was to compare the frictional resistance of titanium, self-ligating stainless steel, and conventional stainless steel brackets, using stainless steel and titanium molybdenum alloy (TMA) archwires. Materials and Methods: We compared the frictional resistance in 0.018 slot and 0.022 slot of the three brackets – titanium, self-ligating stainless steel, and conventional stainless steel – using stainless steel archwires and TMA archwires. An in vitro study of simulated canine retraction was undertaken to evaluate the difference in frictional resistance between titanium, self-ligating stainless steel, and stainless steel brackets, using stainless steel and TMA archwires. Results and Conclusion: We compared the frictional resistance of titanium, self-ligating stainless steel, and conventional stainless steel brackets, using stainless steel and TMA archwires, with the help of Instron Universal Testing Machine. One-way analysis of variance (ANOVA), Student's “t” test, and post hoc multiple range test at level of <0.05 showed statistically significant difference in the mean values of all groups. Results demonstrated that the titanium, self-ligating stainless steel, and stainless steel brackets of 0.018-inch and 0.022-inch slot had no significant variations in frictional résistance. The self-ligating bracket with TMA archwires showed relatively less frictional resistance compared with the other groups. The titanium bracket with TMA archwires showed relatively less frictional resistance compared with the stainless steel brackets. PMID:23066253

  10. Carbon fiber reinforced plastic (CFRP) plates versus stainless steel dynamic compression plates in the treatment of fractures of the tibiae in dogs.

    PubMed

    Skirving, A P; Day, R; Macdonald, W; McLaren, R

    1987-11-01

    In a series of 14 dogs, fractures of both tibiae were caused by a "bone-breaker" designed in the authors' department and observed to produce a consistent and realistic canine fracture. One tibia was plated with a carbon fiber reinforced plastic (CFRP) plate and the other with a dynamic compression (DC) plate. Roentgenographic examination demonstrated healing of the CFRP-plated tibiae with abundant callus, and almost total remodeling of the fracture callus between ten and 20 weeks. Biomechanical testing by three-point bending revealed little difference between the strength of union of the fractures at 12-16 weeks. At 20 weeks, although the numbers were too small for statistical confirmation, the CFRP-plated tibiae were consistently stronger than the DC-plated tibiae. PMID:3665229

  11. Simulations and measurements of artificial cracks and pits in flat stainless steel plates using tone burst eddy-current thermography (TBET)

    NASA Astrophysics Data System (ADS)

    Libin, M. N.; Balasubramaniam, Krishnan; Maxfield, B. W.; Krishnamurthy, C. V.

    2013-01-01

    Tone Burst Eddy current Thermography (TBET) is a new hybrid, non-contacting, Non-Destructive Evaluation (NDE) method which employs a combination of Pulsed Eddy current Thermography (PEC) and Thermographic Non-Destructive Evaluation (TNDE). For understanding the influence of cracking and pitting on heat generation and flow within a metallic body, a fundamental knowledge of the detailed induced current density distribution in the component under test is required. This information enables us to calculate the amount of heat produced by the defects and how that heat diffuses to the surface where it is imaged. This paper describes simulation work done for artificial pits and cracks within pits on the far surface of poorly conducting metals like stainless steel. The first phase of this investigation simulates the transient thermal distribution for artificial 2D pit and crack-like defects using the finite element package COMSOL multi-physics with the AC/DC module and general heat transfer. Considering the reflection measurement geometry where thermal excitation and temperature monitoring are on the same surface, pitting reduces the material volume thereby contributing to a larger temperature rise for the same thermal energy input. A crack within a pit gives a further increase in temperature above the pure pit baseline. The tone burst frequency can be changed to obtain approximately uniform heating (low frequency) or heating of a thin region at the observation surface. Although front surface temperature changes due to 10% deep far-side pits in a 6 mm thick plate can be measured, it is not yet clear whether a 20% deep crack within this pit can be discriminated against the background. Both simulations and measurements will be presented. The objective of this work is to determine whether the TBET method is suitable for the detection and characterization of far side pitting, cracking and cracks within those pits.

  12. Corrosion of stainless steel, 2. edition

    SciTech Connect

    Sedriks, A.J.

    1996-10-01

    The book describes corrosion characteristics in all the major and minor groups of stainless steels, namely, in austenitic, ferritic, martensitic, duplex, and precipitation hardenable steels. Several chapters are spent on those special forms of corrosion that are investigated in the great detail in stainless steels, namely, pitting corrosion, crevice corrosion, and stress corrosion cracking. The influences of thermal treatment (heat affected zone cases), composition, and microstructure on corrosion are given good coverage. Corrosive environments include high temperature oxidation, sulfidation as well as acids, alkalis, various different petroleum plant environments, and even human body fluids (stainless steels are commonly used prosthetic materials).

  13. Duplex stainless steels for osteosynthesis devices.

    PubMed

    Cigada, A; Rondelli, G; Vicentini, B; Giacomazzi, M; Roos, A

    1989-09-01

    The austenitic stainless steels used today for the manufacture of osteosynthesis devices are sensitive to crevice corrosion. In this study the corrosion properties of some duplex stainless steels were evaluated and compared to traditional austenitic stainless steels. According to our results the following ranking was established: 23Cr-4Ni less than AISI 316L less than ASTM F138 less than 22Cr-5Ni-3Mo less than 27Cr-31Ni-3.5Mo less than 25Cr-7Ni-4Mo-N. In particular the results showed that the high-performance 25Cr-7Ni-4Mo-N duplex stainless steel, with high molybdenum and nitrogen contents, can be considered not susceptible to crevice corrosion in the human body. The duplex stainless steels have also better mechanical properties at the same degree of cold working compared with austenitic stainless steels. Hence the 25Cr-7Ni-4Mo-N duplex stainless steel can be considered a convenient substitute of ASTM F138 for orthopedic and osteosynthesis devices. PMID:2777835

  14. Tritiated Water Interaction with Stainless Steel

    SciTech Connect

    Glen R. Longhurst

    2007-05-01

    Experiments conducted to study tritium permeation of stainless steel at ambient and elevated temperatures revealed that HT converts relatively quickly to HTO. Further, the HTO partial pressure contributes essentially equally with elemental tritium gas in driving permeation through the stainless steel. Such permeation appears to be due to dissociation of the water molecule on the hot stainless steel surface. There is an equilibrium concentration of HTO vapor above adsorbed gas on the walls of the experimental apparatus evident from freezing transients. The uptake process of tritium from the carrier gas involves both surface adsorption and isotopic exchange with surface bound water.

  15. Precise carbon control of fabricated stainless steel

    DOEpatents

    Nilsen, R.J.

    1975-12-01

    A process is described for controlling the carbon content of fabricated stainless steel components including the steps of heat treating the component in hydrogen atmospheres of varying dewpoints and carbon potentials.

  16. Hydrogen compatibility handbook for stainless steels

    SciTech Connect

    Caskey, G.R. Jr.

    1983-06-01

    This handbook compiles data on the effects of hydrogen on the mechanical properties of stainless steels and discusses this data within the context of current understanding of hydrogen compatibility of metals. All of the tabulated data derives from continuing studies of hydrogen effects on materials that have been conducted at the Savannah River Laboratory over the past fifteen years. Supplementary data from other sources are included in the discussion. Austenitic, ferritic, martensitic, and precipitation hardenable stainless steels have been studied. Damage caused by helium generated from decay of tritium is a distinctive effect that occurs in addition to the hydrogen isotopes protium and deuterium. The handbook defines the scope of our current knowledge of hydrogen effects in stainless steels and serves as a guide to selection of stainless steels for service in hydrogen.

  17. Development of a carburizing stainless steel alloy

    SciTech Connect

    Wert, D.E. )

    1994-06-01

    A new carburizing stainless steel alloy that resists corrosion, heat, and fatigue has been developed for bearing and gear applications. Pyrowear 675 Stainless alloy is vacuum induction melted and vacuum arc remelted (VIM/VAR) for aircraft-quality cleanliness. Test results show that it has corrosion resistance similar to that of AISI Type 440-C stainless, and its rolling fatigue resistance is superior to that of AISI M50 (UNS K88165). In contrast to alloy gear steels and Type 440C, Pyrowear 675 maintains case hardness of HRC 60 at operating temperatures up to 200 C (400 F). Impact and fracture toughness are superior to that of other stainless bearing steels, which typically are relatively brittle and can break under severe service. Toughness is also comparable or superior to conventional noncorrosion-resistant carburizing bearing steels, such as SAE Types 8620 and 9310.

  18. Stainless steel to titanium bimetallic transitions

    NASA Astrophysics Data System (ADS)

    Kaluzny, J. A.; Grimm, C.; Passarelli, D.

    2015-12-01

    In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels and is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented. Operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy.

  19. Stainless Steel to Titanium Bimetallic Transitions

    SciTech Connect

    Kaluzny, J. A.; Grimm, C.; Passarelli, D.

    2015-01-01

    In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels and is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented.

  20. A Duplex Stainless Steel for Chloride Environments

    NASA Astrophysics Data System (ADS)

    Sridhar, N.; Kolts, J.; Flasche, L. H.

    1985-03-01

    This paper examines the effects of microstructural changes on the corrosion, stress corrosion cracking and corrosion fatigue resistance of a duplex stainless steel to chloride environments. The microstructural changes can be precipitation of phases such as sigma and carbides, or changes in the distribution of austenite and ferrite. The former can be important in hot forming operations while the latter is important in welding. The methods of minimizing these deleterious effects can sometimes be different from those used for austenitic stainless steel.

  1. The abrasion-wear resistance of arc sprayed stainless steel and composite stainless steel coatings

    SciTech Connect

    Dallaire, S.; Legoux, J.G.; Levert, H.

    1994-12-31

    Stainless steels are often used to palliate wear problems in various industries. Though they are not wear resistant, they have been used to a limited extent in applications involving both corrosive and abrasive/erosive environments. The protection of industrial components by arc sprayed stainless steel composite coatings could be considered very attractive provided these coatings offer a better wear protection than bulk stainless steel. The wear resistance of stainless steel and composite stainless steel-titanium boride coatings arc sprayed with air and argon was evaluated following the ASTM G-65 Abrasion Wear Test procedures. Wear volume loss measurements show that stainless steel coatings arc sprayed with air were slightly more resistant than bulk stainless steel while those sprayed with argon were slightly less resistant. The abrasion wear resistance of composite stainless steel-titanium diboride coatings is by two or four times beyond the wear resistance of bulk stainless steel depending upon the core wire constitution and the type of gas used for spraying. Microstructural analysis of coatings, microhardness measurements of sprayed lamellae and optical profilometry were used to characterize coatings and wear damages. Spraying with air instead of argon produced much more small particles. These particles, being removed from the metal sheath surface, are individually sprayed without diluting the concentration hard phases within cores. It results in coatings that contain large lamellae with hardnesses sufficient to withstand abrasion. By considering both the wire constitution and the spraying conditions, it was found possible to fabricate composite stainless steel coatings that show a 400% increase in wear resistance over bulk stainless steel.

  2. Cleaning, pickling, and passivation of stainless steels

    SciTech Connect

    Dillon, C.P. )

    1994-05-01

    Stainless steels (SS) are chosen for various services because of their appearance and corrosion resistance and for their freedom from contamination in storage and shipment. However, certain conditions in handling or fabrication may make these alloys susceptible to localized corrosion or unsatisfactory performance. A surface of cleanliness, uniformity, and corrosion resistance is desirable and, in some services, absolutely required. Definitions and procedures for cleaning, pickling, and passivating stainless steels are reviewed. Surface contamination and defects including grinding marks and smut are discussed, as are measures for preventing and correcting them. The cleaning and passivating sequence required for free-machining stainless grades is included.

  3. Ex situ evaluation of nanometer range gold coating on stainless steel substrate for automotive polymer electrolyte membrane fuel cell bipolar plate

    NASA Astrophysics Data System (ADS)

    Kumar, A.; Ricketts, M.; Hirano, S.

    The bipolar plate in polymer electrolyte membrane (PEM) fuel cell helps to feed reactant gases to the membrane electrode assembly (MEA) and collect current from the MEA. To facilitate these functions, the bipolar plate material should exhibit excellent electrical conductivity and corrosion resistance under fuel cell operating conditions, and simultaneously be of low-cost to meet commercialization enabling targets for automotive fuel cells. In the present work, we focus on the benchmarking of 10 nm gold coated SS316L (a.k.a. Au Nanoclad ®) bipolar plate material through ex situ tests, which is provided by Daido Steel (Japan). The use of nanometer range Au coatings help to retain the noble properties of gold while significantly reducing the cost of the bipolar plate. The area specific resistance of the flat sample is 0.9 mΩ cm 2 while that for the formed bipolar plate is 6.3 mΩ cm 2 at compaction force of 60 N cm -2. The corrosion current density was less than 1 μA cm -2 at 0.8 V/NHE with air sparge simulating cathodic conditions. Additionally, gold coated SS316L showed anodic passivation of SS316L, thereby exhibiting robustness towards coating defects including surface scratches that may originate during the manufacturing of the bipolar plate. These series of ex situ tests indicate that 10 nm gold coated SS316L has good potential to be considered for commercial bipolar plates in automotive fuel cell stack.

  4. High Mn austenitic stainless steel

    DOEpatents

    Yamamoto, Yukinori [Oak Ridge, TN; Santella, Michael L [Knoxville, TN; Brady, Michael P [Oak Ridge, TN; Maziasz, Philip J [Oak Ridge, TN; Liu, Chain-tsuan [Knoxville, TN

    2010-07-13

    An austenitic stainless steel alloy includes, in weight percent: >4 to 15 Mn; 8 to 15 Ni; 14 to 16 Cr; 2.4 to 3 Al; 0.4 to 1 total of at least one of Nb and Ta; 0.05 to 0.2 C; 0.01 to 0.02 B; no more than 0.3 of combined Ti+V; up to 3 Mo; up to 3 Co; up to 1W; up to 3 Cu; up to 1 Si; up to 0.05 P; up to 1 total of at least one of Y, La, Ce, Hf, and Zr; less than 0.05 N; and base Fe, wherein the weight percent Fe is greater than the weight percent Ni, and wherein the alloy forms an external continuous scale including alumina, nanometer scale sized particles distributed throughout the microstructure, the particles including at least one of NbC and TaC, and a stable essentially single phase FCC austenitic matrix microstructure that is essentially delta-ferrite-free and essentially BCC-phase-free.

  5. Forming "dynamic" membranes on stainless steel

    NASA Technical Reports Server (NTRS)

    Brandon, C. A.; Gaddis, J. L.

    1979-01-01

    "Dynamic" zirconium polyacrylic membrane is formed directly on stainless steel substrate without excessive corrosion of steel. Membrane is potentially useful in removal of contaminated chemicals from solution through reversed osmosis. Application includes use in filtration and desalination equipment, and in textile industry for separation of dyes from aqueous solvents.

  6. Corrosion behavior of sensitized duplex stainless steel.

    PubMed

    Torres, F J; Panyayong, W; Rogers, W; Velasquez-Plata, D; Oshida, Y; Moore, B K

    1998-01-01

    The present work investigates the corrosion behavior of 2205 duplex stainless steel in 0.9% NaCl solution after various heat-treatments, and compares it to that of 316L austenitic stainless steel. Both stainless steels were heat-treated at 500, 650, and 800 degrees C in air for 1 h, followed by furnace cooling. Each heat-treated sample was examined for their microstructures and Vickers micro-hardness, and subjected to the X-ray diffraction for the phase identification. Using potentiostatic polarization method, each heat-treated sample was corrosion-tested in 37 degrees C 0.9% NaCl solution to estimate its corrosion rate. It was found that simulated sensitization showed an adverse influence on both steels, indicating that corrosion rates increased by increasing the sensitization temperatures. PMID:9713683

  7. Superplastic forming of stainless steel automotive components

    SciTech Connect

    Bridges, B.; Elmer, J.; Carol, L.

    1997-02-06

    Exhaust emission standards are governmentally controlled standards, which are increasingly stringent, forcing alternate strategies to meet these standards. One approach to improve the efficiency of the exhaust emission equipment is to decrease the time required to get the catalytic converter to optimum operating temperature. To accomplish this, automotive manufacturers are using double wall stainless steel exhaust manifolds to reduce heat loss of the exhaust gases to the converter. The current method to manufacture double wall stainless steel exhaust components is to use a low-cost alloy with good forming properties and extensively form, cut, assemble, and weld the pieces. Superplastic forming (SPF) technology along with alloy improvements has potential at making this process more cost effective. Lockheed Martin Energy Systems (LMES), Lawrence Livermore National Laboratory (LLNL) and USCAR Low Emission Partnership (LEP) worked under a Cooperative Research And Development Agreement (CRADA) to evaluate material properties, SPF behavior, and welding behavior of duplex stainless steel alloy for automotive component manufacturing. Battelle Pacific Northwest National Laboratory (PNNL) has a separate CRADA with the LEP to use SPF technology to manufacture a double wall stainless steel exhaust component. As a team these CRADAs developed and demonstrated a technical plan to accomplish making double wall stainless steel exhaust manifolds.

  8. Casting Stainless-Steel Models Around Pressure Tubes

    NASA Technical Reports Server (NTRS)

    Vasquez, Peter; Micol, John R.

    1992-01-01

    Survivability of thin-wall stainless-steel tubing increased to nearly 100 percent. Improves state of art in pressure-model castings and reduces cost associated with machining complete model from stainless-steel blank.

  9. Direct observation of the passive layer on high nitrogen stainless steel used as bipolar plates for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Kumagai, Masanobu; Myung, Seung-Taek; Yashiro, Hitoshi; Katada, Yasuyuki

    2012-07-01

    The purpose of this report is to directly observe the passive layer and concentration behavior of nitrogen interstitially incorporated in Ni-saving high nitrogen stainless steel (HNS) using an aberration corrected scanning transmission electron microscopy-energy dispersive spectroscopy (STEM-EDS) or - electron energy loss spectroscopy (EELS). The thickness of the passive layer barely changed after 1000 h single cell operation, compared with the as-polished state. The observed passive layer was thin (3 nm) and mainly composed of chromium oxide, as confirmed by STEM-EDS. It was confirmed that nitrogen was not present in the passive layer, but was concentrated at the interface between the passive layer and the metal bulk. The concentrated area ranged approximately 2 nm to steel bulk from the interface. With help of the STEM-EDS and EELS, we were able to understand the nature of the passive layer for Ni-saving HNS, which caused remarkable improvement of the cell performance due to superior corrosion resistance.

  10. Measuring secondary phases in duplex stainless steels

    NASA Astrophysics Data System (ADS)

    Calliari, I.; Brunelli, K.; Dabalà, M.; Ramous, E.

    2009-01-01

    The use of duplex stainless steels is limited by their susceptibility to the formation of dangerous intermetallic phases resulting in detrimental effects on impact toughness and corrosion resistance. This precipitation and the quantitative determinations of the phases have received considerable attention and different precipitation sequences (σ phase, χ phase, and carbides) have been suggested. This study investigates the phase transformation during continuous cooling and isothermal treatments in commercial duplex stainless steel grades and the effects on alloy properties, and compares the most common techniques of analysis.

  11. Embrittlement of austenitic stainless steel welds

    SciTech Connect

    David, S.A.; Vitek, J.M.; Alexander, D.J.

    1995-06-01

    To prevent hot-cracking, austenitic stainless steel welds generally contain a small percent of delta ferrite. Although ferrite has been found to effectively prevent hot-cracking, it can lead to embrittlement of welds when exposed to elevated temperatures. The aging behavior of type-308 stainless steel weld has been examined over a range of temperatures 475--850 C for times up to 10,000 hrs. Upon aging, and depending on the temperature range, the unstable ferrite may undergo a variety of solid state transformations. These phase changes creep-rupture and Charpy impact properties.

  12. Dendritic inhomogeneity of stainless maraging steels

    SciTech Connect

    Krasnikova, S.I.; Drobot, A.V.; Shmelev, A.Y.; Vukelich, S.B.

    1986-03-01

    The authors investigated dendritic inhomogeneity in industrial ingots 630 mm (steel I) in diameter and 500 mm (steel II) in diameter. The variation in the degree of dendritic inhomogeneity was investigated over the height of the ingots and across the sections on an MS-46 microprobe. It was established that the elements can be placed in the following order in accordance with the degree of reduction in the liquation factor: titanium, molybdenum, nickel, chromium, and cobalt. Titanium and molybdenum exhibit forward liquation in both steels, and chromium in steel II. The distribution of nickel and chromium in the steel I ingots and cobalt in the steel II ingots is unconventional. Dendritic inhomogeneity, which must be considered in assigning the heat treatment for finished articles, develops during the crystallization of stainless maraging steels.

  13. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Gold or stainless steel cusp. 872.3350 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or...

  14. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Gold or stainless steel cusp. 872.3350 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or...

  15. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Gold or stainless steel cusp. 872.3350 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or...

  16. 21 CFR 878.4495 - Stainless steel suture.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Stainless steel suture. 878.4495 Section 878.4495...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled nonabsorbable surgical suture composed of...

  17. 21 CFR 878.4495 - Stainless steel suture.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Stainless steel suture. 878.4495 Section 878.4495...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled nonabsorbable surgical suture composed of...

  18. 21 CFR 878.4495 - Stainless steel suture.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Stainless steel suture. 878.4495 Section 878.4495...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled nonabsorbable surgical suture composed of...

  19. 21 CFR 878.4495 - Stainless steel suture.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Stainless steel suture. 878.4495 Section 878.4495...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled nonabsorbable surgical suture composed of...

  20. 21 CFR 878.4495 - Stainless steel suture.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Stainless steel suture. 878.4495 Section 878.4495...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled nonabsorbable surgical suture composed of...

  1. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gold or stainless steel cusp. 872.3350 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or...

  2. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gold or stainless steel cusp. 872.3350 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or...

  3. Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing.

    PubMed

    Luecke, William E; Slotwinski, John A

    2014-01-01

    Using uniaxial tensile and hardness testing, we evaluated the variability and anisotropy of the mechanical properties of an austenitic stainless steel, UNS S17400, manufactured by an additive process, selective laser melting. Like wrought materials, the mechanical properties depend on the orientation introduced by the processing. The recommended stress-relief heat treatment increases the tensile strength, reduces the yield strength, and decreases the extent of the discontinuous yielding. The mechanical properties, assessed by hardness, are very uniform across the build plate, but the stress-relief heat treatment introduced a small non-uniformity that had no correlation to position on the build plate. Analysis of the mechanical property behavior resulted in four conclusions. (1) The within-build and build-to-build tensile properties of the UNS S17400 stainless steel are less repeatable than mature engineering structural alloys, but similar to other structural alloys made by additive manufacturing. (2) The anisotropy of the mechanical properties of the UNS S17400 material of this study is larger than that of mature structural alloys, but is similar to other structural alloys made by additive manufacturing. (3) The tensile mechanical properties of the UNS S17400 material fabricated by selective laser melting are very different from those of wrought, heat-treated 17-4PH stainless steel. (4) The large discontinuous yielding strain in all tests resulted from the formation and propagation of Lüders bands. PMID:26601037

  4. Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing

    PubMed Central

    Luecke, William E; Slotwinski, John A

    2014-01-01

    Using uniaxial tensile and hardness testing, we evaluated the variability and anisotropy of the mechanical properties of an austenitic stainless steel, UNS S17400, manufactured by an additive process, selective laser melting. Like wrought materials, the mechanical properties depend on the orientation introduced by the processing. The recommended stress-relief heat treatment increases the tensile strength, reduces the yield strength, and decreases the extent of the discontinuous yielding. The mechanical properties, assessed by hardness, are very uniform across the build plate, but the stress-relief heat treatment introduced a small non-uniformity that had no correlation to position on the build plate. Analysis of the mechanical property behavior resulted in four conclusions. (1) The within-build and build-to-build tensile properties of the UNS S17400 stainless steel are less repeatable than mature engineering structural alloys, but similar to other structural alloys made by additive manufacturing. (2) The anisotropy of the mechanical properties of the UNS S17400 material of this study is larger than that of mature structural alloys, but is similar to other structural alloys made by additive manufacturing. (3) The tensile mechanical properties of the UNS S17400 material fabricated by selective laser melting are very different from those of wrought, heat-treated 17-4PH stainless steel. (4) The large discontinuous yielding strain in all tests resulted from the formation and propagation of Lüders bands. PMID:26601037

  5. A role of {delta}-ferrite in edge-crack formation during hot-rolling of austenitic stainless steels

    SciTech Connect

    Czerwinski, F.; Brodtka, A.; Cho, J.Y.; Szpunar, J.A.; Zielinska-Lipiec, A.; Sunwoo, J.H.

    1997-10-15

    Austenitic stainless steels are substantially harder during hot-rolling than either ferritic or mild steels. The objective of this study is to verify the possible correlation between the edge-crack formation during hot-rolling and the presence of {delta} ferrite in austenitic stainless steel. Hot-rolled plates of austenitic stainless steels, examined at room temperatures, contain up to 9% of {delta} ferrite in austenitic matrix. The distribution of ferrite in steel plate is inhomogeneous: the highest ferrite content is located in the vicinity of the plate edge. Moreover, the content of {delta} ferrite changes irregularly across the plate thickness. The results obtained from analysis of several plates suggest a correlation between the maximum content of {delta} ferrite in steel microstructure and the length of the edge-crack formed during hot-rolling: the higher the volume fraction of ferrite, the longer the edge-crack.

  6. Technique to eliminate helium induced weld cracking in stainless steels

    SciTech Connect

    Chin-An Wang; Chin, B.A.; Grossbeck, M.L.

    1992-12-31

    Experiments have shown that Type 316 stainless steel is susceptible to heat-affected-zone (HAZ) cracking upon cooling when welded using the gas tungsten arc (GTA) process under lateral constraint. The cracking has been hypothesized to be caused by stress-assisted helium bubble growth and rupture at grain boundaries. This study utilized an experimental welding setup which enabled different compressive stresses to be applied to the plates during welding. Autogenous GTA welds were produced in Type 316 stainless steel doped with 256 appm helium. The application of a compressive stress, 55 Mpa, during welding suppressed the previously observed catastrophic cracking. Detailed examinations conducted after welding showed a dramatic change in helium bubble morphology. Grain boundary bubble growth along directions parallel to the weld was suppressed. Results suggest that stress-modified welding techniques may be used to suppress or eliminate helium-induced cracking during joining of irradiated materials.

  7. Glow discharge cleaning of carbon fiber composite and stainless steel

    NASA Astrophysics Data System (ADS)

    Airapetov, A.; Begrambekov, L.; Brémond, S.; Douai, D.; Kuzmin, A.; Sadovsky, Ya.; Shigin, P.; Vergasov, S.

    2011-08-01

    The paper experimentally investigates and analyses the features and mechanisms of both of oxygen removal by deuterium glow discharge from CFC, pyrolytic graphite and stainless steel subjected to irradiation in oxygen contaminated plasma. It is shown that oxygen implanted in pyrolytic graphite (PG) perpendicular to basal plates is removed after sputtering the layer slightly thicker than oxygen stopping zone (≈2 nm). Fast deuterium ions penetrating into CFC during GDC transfer the trapped oxygen atoms into the bulk. Thus, much thicker surface layer has to be removed (500-1000 nm) for oxygen release. Irradiation of stainless steel in plasma leads to formation of a barrier layer with thickness (2-4 nm) equal, or slightly higher than stopping range of oxygen ions. The layer accumulates the main fraction of implanted oxygen and prevents its penetration into the bulk. After barrier layer sputtering oxygen spreads into the bulk. Parameters and conditions of optimum GDC are discussed.

  8. Emissivity of sodium wetted and oxidized Type 304 stainless steel

    SciTech Connect

    Haines, N.L.; Craig, R.E.; Forsyth, D.R.; Novendstern, E.H.

    1980-01-01

    The emissivity of sodium wetted and oxidized Type 304 stainless steel was determined to provide data for calculating the heat flow through Liquid Metal Fast Breeder Reactor (LMFBR) reflector plates, located above the sodium pool, to the reactor closure head. An emissivity experiment using a Type 304 stainless steel specimen was performed in an inerted glovebox. Relatively high oxygen concentrations of 10,000 and 50 vppm were used in the argon/oxygen mixtures to reduce reaction time. Following wetting and oxidation, the specimen was heated to a maximum temperature of 450/sup 0/C and the emissivity of the oxidized coating was calculated. Results indicate that the emissivity of the coating ranged from 0.55 to 0.92.

  9. Long-Term Underground Corrosion of Stainless Steels

    SciTech Connect

    M. K. Adler Flitton; T. S. Yoder

    2007-03-01

    In 1970, the National Institute of Standards and Technology (NIST) implemented the most ambitious and comprehensive long-term corrosion behavior test to date for stainless steels in soil environments. Over thirty years later, one of the six test sites was targeted to research subsurface contamination and transport processes in the vadose and saturated zones. This research directly applies to environmental management operational corrosion issues and long term stewardship scientific needs for understanding the behavior of waste forms and their near-field contaminant transport of chemical and radiological contaminants at nuclear disposal sites. This paper briefly describes the ongoing research and the corrosion analysis results of the stainless steel plate specimens recovered from the partial recovery of the first test site.

  10. ASTM update for stainless steels II

    SciTech Connect

    Davison, R.M.

    1999-10-01

    Specifiers and users of stainless steel (SS) should be aware that the American Society for Testing and Materials (ASTM) has revised several of its SS specifications. These changes affect grades commonly used in process and other industries. These changes are discussed.

  11. Proof Testing Of Stainless-Steel Bolts

    NASA Technical Reports Server (NTRS)

    Hsieh, Cheng H.; Hendrickson, James A.; Bamford, Robert M.

    1992-01-01

    Report describes study of development of method for nondestructive proof testing of bolts made of A286 stainless steel. Based on concept that the higher load bolt survives, the smaller the largest flaw and, therefore, the longer its fatigue life after test. Calculations and experiments increase confidence in nondestructive proof tests.

  12. Materials data handbooks on stainless steels

    NASA Technical Reports Server (NTRS)

    Muraca, R. F.; Whittick, J. S.

    1973-01-01

    Two handbooks which summarize latest available data have been published. Two types of stainless steels, alloy A-286 and Type 301, are described. Each handbook is divided into twelve chapters. Scope of information presented includes physical- and mechanical-property data at cryogenic, ambient, and elevated temperatures.

  13. Materials data handbook: Stainless steel type 301

    NASA Technical Reports Server (NTRS)

    Muraca, R. F.; Whittick, J. S.

    1972-01-01

    A summary of the materials property information for stainless steel type 301 is presented. The scope of the information includes physical and mechanical properties at cryogenic, ambient, and elevated temperatures. Information on material procurement, metallurgy of the alloy, corrosion, environmental effects, fabrication, and bonding is developed.

  14. Fabrication of stainless steel foil utilizing chromized steel strip

    NASA Astrophysics Data System (ADS)

    Loria, Edward A.

    1980-10-01

    Stainless steel foil has properties which are, in many respects, unmatched by alternative thin films. The high strength to weight ratio and resistance to corrosion and oxidation at elevated temperatures are generally advantageous. The aerospace and automotive industries have used Type 430 and 304 foil in turbine engine applications. Foil around 2 mils (5.1 × 10-3 cm) thick has been appropriate for the recuperator or heat exchanger and this product has also been used in honeycomb and truss-core structures. Further, such foil has been employed as a wrap to protect tool steel parts from contamination during heat treating. A large part of the high cost of producing stainless steel foil by rolling is due to the complicated and expensive rolling mill and annealing equipment involved. A method will be described which produces (solid) stainless steel foil from chromized (coated) steel which can be cheaper than the conventional processing stainless steel, such as Type 430, from ingot to foil. Also, the material is more ductile and less work hardenable during processing to foil and consequently intermediate annealing treatments are eliminated and scrap losses minimized.

  15. 77 FR 2032 - Certain Cut-to-Length Carbon-Quality Steel Plate Products From the Republic of Korea: Preliminary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ... as stated in Stainless Steel Sheet and Strip in Coils From Mexico; Preliminary Results of Antidumping Duty Administrative Review, 73 FR 45708, 45714 (August 6, 2008), unchanged in Stainless Steel Sheet and... International Trade Administration Certain Cut-to-Length Carbon-Quality Steel Plate Products From the...

  16. Microstructural characterization in dissimilar friction stir welding between 304 stainless steel and st37 steel

    SciTech Connect

    Jafarzadegan, M.; Feng, A.H.; Abdollah-zadeh, A.; Saeid, T.; Shen, J.; Assadi, H.

    2012-12-15

    In the present study, 3 mm-thick plates of 304 stainless steel and st37 steel were welded together by friction stir welding at a welding speed of 50 mm/min and tool rotational speed of 400 and 800 rpm. X-ray diffraction test was carried out to study the phases which might be formed in the welds. Metallographic examinations, and tensile and microhardness tests were used to analyze the microstructure and mechanical properties of the joint. Four different zones were found in the weld area except the base metals. In the stir zone of the 304 stainless steel, a refined grain structure with some features of dynamic recrystallization was evidenced. A thermomechanically-affected zone was characterized on the 304 steel side with features of dynamic recovery. In the other side of the stir zone, the hot deformation of the st37 steel in the austenite region produced small austenite grains and these grains transformed to fine ferrite and pearlite and some products of displacive transformations such as Widmanstatten ferrite and martensite by cooling the material after friction stir welding. The heat-affected zone in the st37 steel side showed partially and fully refined microstructures like fusion welding processes. The recrystallization in the 304 steel and the transformations in the st37 steel enhanced the hardness of the weld area and therefore, improved the tensile properties of the joint. - Highlights: Black-Right-Pointing-Pointer FSW produced sound welds between st37 low carbon steel and 304 stainless steel. Black-Right-Pointing-Pointer The SZ of the st37 steel contained some products of allotropic transformation. Black-Right-Pointing-Pointer The material in the SZ of the 304 steel showed features of dynamic recrystallization. Black-Right-Pointing-Pointer The finer microstructure in the SZ increased the hardness and tensile strength.

  17. Market Opportunities for Austenitic Stainless Steels in SO2 Scrubbers

    NASA Astrophysics Data System (ADS)

    Michels, Harold T.

    1980-10-01

    Recent U.S. federal legislation has created new opportunities for SO2 scrubbers because all coals, even low-sulfur western coals, will probably require scrubbing to remove SO2 from gaseous combustion products. Scrubbing, the chemical absorption of SO2 by vigorous contact with a slurry—usually lime or limestone—creates an aggressive acid-chloride solution. This presents a promising market for pitting-resistant austenitic stainless steels, but there is active competition from rubber and fiberglass-lined carbon steel. Since the latter are favored on a first-cost basis, stainless steels must be justified on a cost/performance or life-cost basis. Nickel-containing austenitic alloys are favored because of superior field fabricability. Ferritic stainless steels have little utility in this application because of limitations in weldability and resulting poor corrosion resistance. Inco corrosion test spools indicate that molybdenum-containing austenitic alloys are needed. The leanest alloys for this application are 316L and 317L. Low-carbon grades of stainless steel are specified to minimize corrosion in the vicinity of welds. More highly alloyed materials may be required in critical areas. At present, 16,000 MW of scrubber capacity is operational and 17,000 MW is under construction. Another 29,000 MW is planned, bringing the total to 62,000 MW. Some 160,000 MW of scrubber capacity is expected to be placed in service over the next 10 years. This could translate into a total potential market of 80,000 tons of alloy plate for new power industry construction in the next decade. Retrofitting of existing power plants plus scrubbers for other applications such as inert gas generators for oil tankers, smelters, municipal incinerators, coke ovens, the pulp and paper industry, sulfuric acid plants, and fluoride control in phosphoric acid plants will add to this large market.

  18. Fatigue of stainless steel in hydrogen

    NASA Astrophysics Data System (ADS)

    Schuster, G.; Altstetter, C.

    1983-10-01

    The fatigue crack growth rates of two austenitic stainless steel alloys, AISI 301 and 302, were compared in air, argon, and hydrogen environments at atmospheric pressure and room temperature. Under the stresses at the crack tip the austenite in type 301 steel transformed martensitically to a’ to a greater extent than in type 302 steel. The steels were also tested in the cold worked condition under hydrogen or argon. Hydrogen was found to have a deleterious effect on both steels, but the effect was stronger in the unstable than in the stable alloy. Cold work decreased fatigue crack growth rates in argon and hydrogen, but the decrease was less marked in hydrogen than in argon. Metallographic, fractographic, and microhardness surveys in the vicinity of the fatigue crack were used to try to understand the reasons for the observed fatigue behavior.

  19. Standard specification for general requirements for steel plates for pressure vessels. ASTM standard

    SciTech Connect

    1998-11-01

    This specification is under the jurisdiction of ASTM Committee A-1 on Steel, Stainless Steel, and Related Alloys and is the direct responsibility of Subcommittee A01.11 on Steel Plates for Boilers and Pressure Vessels. Current edition approved Sep. 10, 1997. Published November 1998. Originally published as A 20-50T. Last previous edition A 20/A 20M-97a.

  20. Tensile-property characterization of thermally aged cast stainless steels.

    SciTech Connect

    Michaud, W. F.; Toben, P. T.; Soppet, W. K.; Chopra, O. K.; Energy Technology

    1994-03-03

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  1. Tensile-property characterization of thermally aged cast stainless steels

    SciTech Connect

    Michaud, W.F.; Toben, P.T.; Soppet, W.K.; Chopra, O.K.

    1994-02-01

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  2. Corrosion Testing of Stainless Steel Fuel Cell Hardware

    SciTech Connect

    Wilson, M.S.; Zawodzinski, C.; Gottesfeld, S.

    1998-11-01

    Metal hardware is gaining increasing interest in polymer electrolyte fuel cell (PEFC) development as a possible alternative to machined graphite hardware because of its potential for low-cost manufacturing combined with its intrinsic high conductivity, minimal permeability and advantageous mechanical properties. A major barrier to more widespread use of metal hardware has been the susceptibility of various metals to corrosion. Few pure metals can withstand the relatively aggressive environment of a fuel cell and thus the choices for hardware are quite limited. Precious metals such as platinum or gold are prohibitively expensive and so tend to be utilized as coatings on inexpensive substrates such as aluminum or stainless steel. The main challenge with coatings has been to achieve pin-hole free surfaces that will remain so after years of use. Titanium has been used to some extent and though it is very corrosion-resistant, it is also relatively expensive and often still requires some manner of surface coating to prevent the formation of a poorly conducting oxide layer. In contrast, metal alloys may hold promise as potentially low-cost, corrosion-resistant materials for bipolar plates. The dozens of commercially available stainless steel and nickel based alloys have been specifically formulated to offer a particular advantage depending upon their application. In the case of austenitic stainless steels, for example, 316 SS contains molybdenum and a higher chromium content than its more common counterpart, 304 SS, that makes it more noble and increases its corrosion resistance. Likewise, 316L SS contains less carbon than 316 SS to make it easier to weld. A number of promising corrosion-resistant, highly noble alloys such as Hastelloy{trademark} or Duplex{trademark} (a stainless steel developed for seawater service) are available commercially, but are expensive and difficult to obtain in various forms (i.e. wire screen, foil, etc.) or in small amounts for R and D

  3. Growth and adherence on stainless steel by Enterococcus faecium cells.

    PubMed

    Andrade, N J; Ajao, D B; Zottola, E A

    1998-11-01

    Enterococcus faecium isolated from Brazilian raw milk was used in this study. For growth studies, E. faecium was inoculated into 10% RSM (reconstituted skim milk) and MRS both, incubated at 6.5 and 9 degrees C for 10 days and at 30, 42, and 45 degrees C for 48 h. Cells were enumerated after spread-plating onto MRS agar and incubating at 30 degrees C for 48 h. The ability of E. faecium cells to adhere to stainless-steel chips (6 by 6 by 1 mm, AISI 304, finish #4) was investigated. MRS broth containing stainless steel chips was inoculated to an initial concentration of 10(3) or 10(6) CFU/ml of E. faecium. Adherent cells were stained with acridine orange and enumerated by epifluorescence microscopy. E. faecium grew between 6.5 and 42 degrees C in MRS and between 9 and 40 degrees C in RSM. In MRS broth with 10(6) or 10(3) CFU/ml, the g (generation time) values were 0.62 and 0.42 h and R (growth rate) values were 1.6 and 2.4 h-1. Values of R = 2.3 h-1 and g = 0.43 h were determined for E. faecium growing in RSM with 10(3) CFU/ml. In MRS broth, for samples with a starting concentration of 10(6) cells per ml, adherence to stainless-steel chips was first observed at 2 h. However, adherence was first observed at 4 h in samples with an initial concentration of 10(3) cells per ml. After 10 h of exposure the number of adherent cells was similar for all samples regardless of initial inoculum. These results indicate that E. faecium readily adheres to stainless steel. It also underscores the need to control E. faecium by using appropriate low storage temperatures and adequate sanitizing practices in the dairy industry. PMID:9829184

  4. Phase Transformation in Cast Superaustenitic Stainless Steels

    SciTech Connect

    Nathaniel Steven Lee Phillips

    2006-12-12

    Superaustenitic stainless steels constitute a group of Fe-based alloys that are compositionally balanced to have a purely austenitic matrix and exhibit favorable pitting and crevice corrosion resistant properties and mechanical strength. However, intermetallic precipitates such as sigma and Laves can form during casting or exposure to high-temperature processing, which degrade the corrosion and mechanical properties of the material. The goal of this study was to accurately characterize the solid-solid phase transformations seen in cast superaustenitic stainless steels. Heat treatments were performed to understand the time and temperature ranges for intermetallic phase formations in alloys CN3MN and CK3MCuN. Microstructures were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy and wavelength dispersive spectroscopy (EDS, WDS). The equilibrium microstructures, composed primarily of sigma and Laves within purely austenitic matrices, showed slow transformation kinetics. Factors that determine the extent of transformation, including diffusion, nucleation, and growth, are discussed.

  5. Formability of type 304 stainless steel sheet

    SciTech Connect

    Coubrough, G.J.; Matlock, D.K.; VanTyne, C.J.

    1992-09-01

    Punch-stretch tests to determine formability of type 304 stainless steel sheet were conducted using a hemispherical dome test. Sheets of 19.1 mm width and 177.8 mm width were stretched on a 101.6 mm diameter punch at punch rates between 0.042 to 2.12 mm/s with three lubricant systems: a mineral seal oil, thin polytetrafluoroethelyne sheet with mineral seal oil, and silicone rubber with mineral seal oil. The resulting strain distributions were measured and the amount of martensite was determined by magnetic means. Increasing lubricity resulted in more uniform strain distributions while increased punch rates tended to decrease both strain and transformation distributions. High forming limit values were related to the formation of high and uniformly distributed martensite volume fractions during deformation. The results of this study are interpreted with an analysis of the effects of strain and temperature on strain induced martensite formation in metastable austenitic stainless steels.

  6. Formability of type 304 stainless steel sheet

    SciTech Connect

    Coubrough, G.J. . Rocky Flats Plant); Matlock, D.K.; VanTyne, C.J. )

    1992-01-01

    Punch-stretch tests to determine formability of type 304 stainless steel sheet were conducted using a hemispherical dome test. Sheets of 19.1 mm width and 177.8 mm width were stretched on a 101.6 mm diameter punch at punch rates between 0.042 to 2.12 mm/s with three lubricant systems: a mineral seal oil, thin polytetrafluoroethelyne sheet with mineral seal oil, and silicone rubber with mineral seal oil. The resulting strain distributions were measured and the amount of martensite was determined by magnetic means. Increasing lubricity resulted in more uniform strain distributions while increased punch rates tended to decrease both strain and transformation distributions. High forming limit values were related to the formation of high and uniformly distributed martensite volume fractions during deformation. The results of this study are interpreted with an analysis of the effects of strain and temperature on strain induced martensite formation in metastable austenitic stainless steels.

  7. Tritium Depth Profiles in 316 Stainless Steel

    NASA Astrophysics Data System (ADS)

    Torikai, Yuji; Murata, Daiju; Penzhorn, Ralf-Dieter; Akaishi, Kenya; Watanabe, Kuniaki; Matsuyama, Masao

    To investigate the behavior of hydrogen uptake and release by 316 stainless steel (SS316), as-received and finely polished stainless steel specimens were exposed at 573 K to tritium gas diluted with hydrogen. Then tritium concentration in the exposed specimens was measured as a function of depth using a chemical etching method. All the tritium concentration profiles showed a sharp drop in the range of 10 μm from the top surface up to the bulk. The amount of tritium absorbed into the polished specimens was three times larger than that into the as-received specimen. However, the polishing effects disappeared by exposing to the air for a long time.

  8. Instabilities in stabilized austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Ayer, Raghavan; Klein, C. F.; Marzinsky, C. N.

    1992-09-01

    The effect of aging on the precipitation of grain boundary phases in three austenitic stainless steels (AISI 347, 347AP, and an experimental steel stabilized with hafnium) was investigated. Aging was performed both on bulk steels as well as on samples which were subjected to a thermal treatment to simulate the coarse grain region of the heat affected zone (HAZ) during welding. Aging of the bulk steels at 866 K for 8000 hours resulted in the precipitation of Cr23C6 carbides, σ, and Fe2Nb phases; the propensity for precipitation was least for the hafnium-stabilized steel. Weld simulation of the HAZ resulted in dissolution of the phases present in the as-received 347 and 347AP steels, leading to grain coarsening. Subsequent aging caused extensive grain boundary Cr23C6 carbides and inhomogeneous matrix precipitation. In addition, steel 347AP formed a precipitate free zone (PFZ) along the grain boundaries. The steel containing hafnium showed the best microstructural stability to aging and welding.

  9. Water Lubrication of Stainless Steel using Reduced Graphene Oxide Coating

    NASA Astrophysics Data System (ADS)

    Kim, Hae-Jin; Kim, Dae-Eun

    2015-11-01

    Lubrication of mechanical systems using water instead of conventional oil lubricants is extremely attractive from the view of resource conservation and environmental protection. However, insufficient film thickness of water due to low viscosity and chemical reaction of water with metallic materials have been a great obstacle in utilization of water as an effective lubricant. Herein, the friction between a 440 C stainless steel (SS) ball and a 440 C stainless steel (SS) plate in water lubrication could be reduced by as much as 6-times by coating the ball with reduced graphene oxide (rGO). The friction coefficient with rGO coated ball in water lubrication was comparable to the value obtained with the uncoated ball in oil lubrication. Moreover, the wear rate of the SS plate slid against the rGO coated ball in water lubrication was 3-times lower than that of the SS plate slid against the uncoated ball in oil lubrication. These results clearly demonstrated that water can be effectively utilized as a lubricant instead of oil to lower the friction and wear of SS components by coating one side with rGO. Implementation of this technology in mechanical systems is expected to aid in significant reduction of environmental pollution caused by the extensive use of oil lubricants.

  10. Water Lubrication of Stainless Steel using Reduced Graphene Oxide Coating

    PubMed Central

    Kim, Hae-Jin; Kim, Dae-Eun

    2015-01-01

    Lubrication of mechanical systems using water instead of conventional oil lubricants is extremely attractive from the view of resource conservation and environmental protection. However, insufficient film thickness of water due to low viscosity and chemical reaction of water with metallic materials have been a great obstacle in utilization of water as an effective lubricant. Herein, the friction between a 440 C stainless steel (SS) ball and a 440 C stainless steel (SS) plate in water lubrication could be reduced by as much as 6-times by coating the ball with reduced graphene oxide (rGO). The friction coefficient with rGO coated ball in water lubrication was comparable to the value obtained with the uncoated ball in oil lubrication. Moreover, the wear rate of the SS plate slid against the rGO coated ball in water lubrication was 3-times lower than that of the SS plate slid against the uncoated ball in oil lubrication. These results clearly demonstrated that water can be effectively utilized as a lubricant instead of oil to lower the friction and wear of SS components by coating one side with rGO. Implementation of this technology in mechanical systems is expected to aid in significant reduction of environmental pollution caused by the extensive use of oil lubricants. PMID:26593645

  11. Hydrogen induced plastic deformation of stainless steel

    SciTech Connect

    Gadgil, V.J.; Keim, E.G.; Geijselaers, H.J.M.

    1998-12-31

    Hydrogen can influence the behavior of materials significantly. The effects of hydrogen are specially pronounced in high fugacities of hydrogen which can occur at the surface of steels in contact with certain aqueous environments. In this investigation the effect of high fugacity hydrogen on the surface of stainless steel was investigated using electrochemical cathodic charging. Microhardness was measured on the cross section. Transmission electron microscopy was used to investigate the dislocation substructure just below the surface. Computer simulation using finite element method was carried out to estimate the extent and severity of the deformation. The significance of the results are discussed in relation to the loss of ductility due to hydrogen.

  12. Properties of cryogenically worked metals. [stainless steels

    NASA Technical Reports Server (NTRS)

    Schwartzberg, F. R.; Kiefer, T. F.

    1975-01-01

    A program was conducted to determine whether the mechanical properties of cryogenically worked 17-7PH stainless steel are suitable for service from ambient to cryogenic temperatures. It was determined that the stress corrosion resistance of the cryo-worked material is quite adequate for structural service. The tensile properties and fracture toughness at room temperature were comparable to titanium alloy 6Al-4V. However, at cryogenic temperatures, the properties were not sufficient to recommend consideration for structural service.

  13. Pitting corrosion resistant austenite stainless steel

    DOEpatents

    van Rooyen, D.; Bandy, R.

    A pitting corrosion resistant austenite stainless steel comprises 17 to 28 wt. % chromium, 15 to 26 wt. % nickel, 5 to 8 wt. % molybdenum, and 0.3 to 0.5 wt. % nitrogen, the balance being iron, unavoidable impurities, minor additions made in the normal course of melting and casting alloys of this type, and may optionally include up to 10 wt. % of manganese, up to 5 wt. % of silicon, and up to 0.08 wt. % of carbon.

  14. Softened-Stainless-Steel O-Rings

    NASA Technical Reports Server (NTRS)

    Marquis, G. A.; Waters, William I.

    1993-01-01

    In fabrication of O-ring of new type, tube of 304 stainless steel bent around mandril into circle and welded closed into ring. Ring annealed in furnace to make it soft and highly ductile. In this condition, used as crushable, deformable O-ring seal. O-ring replacements used in variety of atmospheres and temperatures, relatively inexpensive, fabricated with minimum amount of work, amenable to one-of-a-kind production, reusable, and environmentally benign.

  15. Effect of ferrite on cast stainless steels

    SciTech Connect

    Nadezhdin, A.; Cooper, K. ); Timbers, G. . Kraft Pulp Division)

    1994-09-01

    Premature failure of stainless steel castings in bleach washing service is attributed to poor casting quality high porosity and to a high ferrite content, which makes the castings susceptible to corrosion by hot acid chloride solutions. A survey of the chemical compositions and ferrite contents of corrosion-resistant castings in bleach plants at three pulp mills found high [delta]-ferrite levels in the austenitic matrix due to the improper balance between austenite and ferrite stabilizers.

  16. Antimicrobial Cu-bearing stainless steel scaffolds.

    PubMed

    Wang, Qiang; Ren, Ling; Li, Xiaopeng; Zhang, Shuyuan; Sercombe, Timothy B; Yang, Ke

    2016-11-01

    Copper-bearing stainless steel scaffolds with two different structures (Body Centered Cubic and Gyroid labyrinth) at two solid fractions (25% and 40%) were fabricated from both 316L powder and a mixture of 316L and elemental Cu powder using selective laser melting, and relative 316L scaffolds were served as control group. After processing, the antimicrobial testing demonstrated that the 316L-Cu scaffolds presented excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, and the cell viability assay indicated that there was no cytotoxic effect of 316L-Cu scaffolds on rat marrow mesenchymal stem cells. As such, these have the potential to reduce implant-associated infections. The Cu was also found to homogeneously distribute within the microstructure by scanning electronic microcopy. The addition of Cu would not significantly affect its strength and stiffness compared to 316L scaffold, and the stiffness of all the scaffolds (3-20GPa) is similar to that of bone and much less than that of bulk stainless steel. Consequently, fabrication of such low stiffness porous structures, especially coupled with the addition of antimicrobial Cu, may provide a new direction for medical stainless steels. PMID:27524049

  17. SRS stainless steel beneficial reuse program

    SciTech Connect

    Boettinger, W.L.

    1997-02-01

    The US Department of Energy`s (DOE) Savannah River Site (SRS) has thousands of tons of stainless steel radioactive scrap metal (RSNI). Much of the metal is volumetrically contaminated. There is no {open_quotes}de minimis{close_quotes} free release level for volumetric material, and therefore no way to recycle the metal into the normal commercial market. If declared waste, the metal would qualify as low level radioactive waste (LLW) and ultimately be dispositioned through shallow land buried at a cost of millions of dollars. The metal however could be recycled in a {open_quotes}controlled release{close_quote} manner, in the form of containers to hold other types of radioactive waste. This form of recycle is generally referred to as {open_quotes}Beneficial Reuse{close_quotes}. Beneficial reuse reduces the amount of disposal space needed and reduces the need for virgin containers which would themselves become contaminated. Stainless steel is particularly suited for long term storage because of its resistance to corrosion. To assess the practicality of stainless steel RSM recycle the SRS Benficial Reuse Program began a demonstration in 1994, funded by the DOE Office of Science and Technology. This paper discusses the experiences gained in this program.

  18. Cast Stainless Steel Ferrite and Grain Structure

    SciTech Connect

    Ruud, Clayton O.; Ramuhalli, Pradeep; Meyer, Ryan M.; Mathews, Royce; Diaz, Aaron A.; Anderson, Michael T.

    2012-09-01

    In-service inspection requirements dictate that piping welds in the primary pressure boundary of light-water reactors be subject to a volumetric examination based on the rules contained within the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI. The purpose of the inspection is the reliable detection and accurate sizing of service-induced degradation and/or material flaws introduced during fabrication. The volumetric inspection is usually carried out using ultrasonic testing (UT) methods. However, the varied metallurgical macrostructures and microstructures of cast austenitic stainless steel piping and fittings, including statically cast stainless steel and centrifugally cast stainless steel (CCSS), introduce significant variations in the propagation and attenuation of ultrasonic energy. These variations complicate interpretation of the UT responses and may compromise the reliability of UT inspection. A review of the literature indicated that a correlation may exist between the microstructure and the delta ferrite content of the casting alloy. This paper discusses the results of a recent study where the goal was to determine if a correlation existed between measured and/or calculated ferrite content and grain structure in CCSS pipe.

  19. Disinfection of preexisting contamination of bacillus cereus on stainless steel when using glycoconjugate solution

    SciTech Connect

    Pavan, Casey; Tarasenko, Olga

    2011-06-10

    Stainless steel is ubiquitous in our modern world, however it can become contaminated. This can endanger our health. The aim of our study is to disinfect stainless steel using Bacillus cereus as a model organism. Bacillus cereus is a microbe that is ubiquitous in nature, specifically soil. B. cereus is known to cause illness in humans. To prevent this, we propose to use a glycoconjugate solution (GS) for disinfection of stainless steel after it is contamination by B. cereus spores. In this study, two GS (9, 10) were tested for disinfection effectiveness on B. cereus spores on the surface of stainless steel foil (AISI-Series 200/300/400, THERMA-FOIL, Dayville, CT 0241). The disinfection rate of each GS was assessed by exposing the steel surface to B. cereus spores first and allowing them to settle for 24 hours. GS was used to treat the contaminated surface. The steel is washed and the resulting solution is plated on tryptic soy agar (TSA) plates. The GS with the fewest colony forming unit (CFU) formed on TSA is determined to be the most efficient during disinfection. Results show that both GS demonstrate a strong ability to disinfect B. cereus spores. Between the two, GS 9 shows the highest disinfection efficacy by killing approximately 99.5% of spores. This is a drastic improvement over the 0-20% disinfection of the control. Based on this we find that studied GS do have the capacity to act as a disinfectant on stainless steel.

  20. Disinfection of Preexisting Contamination of BACILLUS CEREUS on Stainless Steel when Using Glycoconjugate Solution

    NASA Astrophysics Data System (ADS)

    Pavan, Casey; Tarasenko, Olga

    2011-06-01

    Stainless steel is ubiquitous in our modern world, however it can become contaminated. This can endanger our health. The aim of our study is to disinfect stainless steel using Bacillus cereus as a model organism. Bacillus cereus is a microbe that is ubiquitous in nature, specifically soil. B. cereus is known to cause illness in humans. To prevent this, we propose to use a glycoconjugate solution (GS) for disinfection of stainless steel after it is contamination by B. cereus spores. In this study, two GS (9, 10) were tested for disinfection effectiveness on B. cereus spores on the surface of stainless steel foil (AISI-Series 200/300/400, THERMA-FOIL, Dayville, CT 0241). The disinfection rate of each GS was assessed by exposing the steel surface to B. cereus spores first and allowing them to settle for 24 hours. GS was used to treat the contaminated surface. The steel is washed and the resulting solution is plated on tryptic soy agar (TSA) plates. The GS with the fewest colony forming unit (CFU) formed on TSA is determined to be the most efficient during disinfection. Results show that both GS demonstrate a strong ability to disinfect B. cereus spores. Between the two, GS 9 shows the highest disinfection efficacy by killing approximately 99.5% of spores. This is a drastic improvement over the 0-20% disinfection of the control. Based on this we find that studied GS do have the capacity to act as a disinfectant on stainless steel.

  1. Decontaminating and Melt Recycling Tritium Contaminated Stainless Steel

    SciTech Connect

    Clark, E.A.

    1995-04-03

    The Westinghouse Savannah River Company, Idaho National Engineering Laboratory, and several university and industrial partners are evaluating recycling radioactively contaminated stainless steel. The goal of this program is to recycle contaminated stainless steel scrap from US Department of Energy national defense facilities. There is a large quantity of stainless steel at the DOE Savannah River Site from retired heavy water moderated Nuclear material production reactors (for example heat exchangers and process water piping), that will be used in pilot studies of potential recycle processes. These parts are contaminated by fission products, activated species, and tritium generated by neutron irradiation of the primary reactor coolant, which is heavy (deuterated) water. This report reviews current understanding of tritium contamination of stainless steel and previous studies of decontaminating tritium exposed stainless steel. It also outlines stainless steel refining methods, and proposes recommendations based on this review.

  2. Amorphous stainless steel coatings prepared by reactive magnetron-sputtering from austenitic stainless steel targets

    NASA Astrophysics Data System (ADS)

    Cusenza, Salvatore; Schaaf, Peter

    2009-01-01

    Stainless steel films were reactively magnetron sputtered in argon/methane gas flow onto oxidized silicon wafers using austenitic stainless-steel targets. The deposited films of about 200 nm thickness were characterized by conversion electron Mössbauer spectroscopy, magneto-optical Kerr-effect, X-ray diffraction, scanning electron microscopy, Rutherford backscattering spectrometry, atomic force microscopy, corrosion resistance tests, and Raman spectroscopy. These complementary methods were used for a detailed examination of the carburization effects in the sputtered stainless-steel films. The formation of an amorphous and soft ferromagnetic phase in a wide range of the processing parameters was found. Further, the influence of the substrate temperature and of post vacuum-annealing were examined to achieve a comprehensive understanding of the carburization process and phase formation.

  3. Weldment for austenitic stainless steel and method

    DOEpatents

    Bagnall, Christopher; McBride, Marvin A.

    1985-01-01

    For making defect-free welds for joining two austenitic stainless steel mers, using gas tungsten-arc welding, a thin foil-like iron member is placed between the two steel members to be joined, prior to making the weld, with the foil-like iron member having a higher melting point than the stainless steel members. When the weld is formed, there results a weld nugget comprising melted and then solidified portions of the joined members with small portions of the foil-like iron member projecting into the solidified weld nugget. The portions of the weld nugget proximate the small portions of the foil-like iron member which project into the weld nugget are relatively rich in iron. This causes these iron-rich nugget portions to display substantial delta ferrite during solidification of the weld nugget which eliminates weld defects which could otherwise occur. This is especially useful for joining austenitic steel members which, when just below the solidus temperature, include at most only a very minor proportion of delta ferrite.

  4. Superhard Nanocrystalline Homometallic Stainless Steel on Steel for Seamless Coatings

    NASA Technical Reports Server (NTRS)

    Tobin, Eric J.; Hafley, R. (Technical Monitor)

    2002-01-01

    The objective of this work is to deposit nanocrystalline stainless steel onto steel substrates (homometallic) for enhanced wear and corrosion resistance. Homometallic coatings provide superior adhesion, and it has been shown that ultrafine-grained materials exhibit the increased hardness and decreased permeability desired for protective coatings. Nanocrystals will be produced by controlling nucleation and growth and use of an ion beam during deposition by e-beam evaporation or sputtering. Phase I is depositing 31 6L nanocrystalline stainless steel onto 31 6L stainless steel substrates. These coatings exhibit hardnesses comparable to those normally obtained for ceramic coatings such ZrO2, and possess the superior adhesion of seamless, homometallic coatings. Hardening the surface with a similar material also enhances adhesion, by avoiding problems associated with thermal and lattice mismatch. So far we have deposited nanocrystalline homometallic 316L stainless steel coatings by varying the ions and the current density of the ion beams. For all deposition conditions we have produced smooth, uniform, superhard coatings. All coatings exhibit hardness of at least 200% harder than that of bulk materials. Our measurements indicate that there is a direct relationship between nanohardness and the current density of the ion beam. Stress measurements indicate that stress in the films is increasingly proportional to current density of the ion beam. TEM, XPS, and XRD results indicate that the coated layers consist of FCC structure nanocrystallites with a dimension of about 10 to 20 nm. The Ni and Mo concentration of these coating are lower than those of bulk 316L but the concentration of Cr is higher.

  5. Stainless Steel Leaches Nickel and Chromium into Foods During Cooking

    PubMed Central

    Kamerud, Kristin L.; Hobbie, Kevin A.; Anderson, Kim A.

    2014-01-01

    Toxicological studies show that oral doses of nickel and chromium can cause cutaneous adverse reactions such as dermatitis. Additional dietary sources, such as leaching from stainless steel cookware during food preparation, are not well characterized. This study examined stainless steel grades, cooking time, repetitive cooking cycles, and multiple types of tomato sauces for their effects on nickel and chromium leaching. Trials included three types of stainless steels and a stainless steel saucepan; cooking times of 2 to 20 hours, ten consecutive cooking cycles, and four commercial tomato sauces. After a simulated cooking process, samples were analyzed by ICP-MS for Ni and Cr. After six hours of cooking, Ni and Cr concentrations in tomato sauce increased up to 26- and 7-fold respectively, depending on the grade of stainless steel. Longer cooking durations resulted in additional increases in metal leaching, where Ni concentrations increased 34 fold and Cr increased approximately 35 fold from sauces cooked without stainless steel. Cooking with new stainless steel resulted in the largest increases. Metal leaching decreases with sequential cooking cycles and stabilized after the sixth cooking cycle, though significant metal contributions to foods were still observed. The tenth cooking cycle, resulted in an average of 88 μg of Ni and 86 μg of Cr leached per 126 g serving of tomato sauce. Stainless steel cookware can be an overlooked source of nickel and chromium, where the contribution is dependent on stainless steel grade, cooking time, and cookware usage. PMID:23984718

  6. An understanding of HSLA-65 plate steels

    NASA Astrophysics Data System (ADS)

    Sampath, K.

    2006-02-01

    HSLA-65 plate steels can be produced using one of five plate manufacturing techniques: normalizing, controlled rolling (CR), controlled rolling followed by accelerated cooling (CR-AC), direct quenching and tempering (DQT), or conventional quenching and tempering (Q&T). The HSLA-65 steels are characterized by low carbon content and low alloy content, and they exhibit a low carbon equivalent that allows improved plate weldability. These characteristics in turn (a) provide the steel plate with a refined microstructure that ensures high strength and toughness; (b) eliminate or substantially reduce the need for preheating during welding; (c) resist susceptibility to hydrogen-assisted cracking (HAC) in the weld heat affected zone (HAZ) when fusion (arc) welded using low heat-input conditions; and (d) depending on section thickness, facilitate high heat-input welding (about 2 kJ/mm) without significant loss of strength or toughness in the HAZ. However, application of this plate manufacturing process and of these controls produces significant differences in the metallurgical structure and range of mechanical properties of the HSLA-65 plate steels both among themselves and versus conventional higher strength steel (HSS) plates. For example, among the HSLA-65 plate steels, those produced by Q&T exhibit minimal variability in mechanical properties, especially in thicker plates. Besides variability in mechanical properties depending on plate thickness, the CR and CR-AC plate steels exhibit a relatively higher yield strength to ultimate tensile strength (YS/UTS) ratio than do DQT and Q&T steels. Such differences in processing and properties of HSLA-65 plate steels could potentially affect the selection and control of various secondary fabrication practices, including arc welding. Consequently, fabricators must exercise extreme caution when transferring allowable limits of certified secondary fabrication practices from one type of HSLA-65 plate steel to another, even for the

  7. Corrosive effect of carbon-fibre reinforced plastic on stainless-steel screws during implantation into man.

    PubMed

    Tayton, K

    1983-01-01

    The corrosion of stainless-steel screws used to fix carbon-fibre reinforced plastic (CFRP) plates to human fractures was compared with the corrosion on similar screws used to fix stainless-steel AO plates. Corrosive changes were noted in both sets of screws with similar frequency and severity; however, the stainless-steel plates were 'in situ' almost twice as long as the CFRP ones, showing that the corrosive changes occurred more rapidly on screws in contact with CFRP. Nevertheless, over the implantation time necessary for bone healing, corrosion was very mild and there is no clinical contra-indication to the use of stainless-steel and CFRP together in this particular application. PMID:6842566

  8. 3. INTERIOR VIEW OF SMOKEHOUSE UNIT; NOTE STAINLESS STEEL NOZZLES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. INTERIOR VIEW OF SMOKEHOUSE UNIT; NOTE STAINLESS STEEL NOZZLES THAT INTRODUCED SMOKE INTO UNIT; FLOOR IS UNPAINTED STEEL - Rath Packing Company, Smokehouse-Hog Chilling Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  9. Nanostructured nickel-free austenitic stainless steel/hydroxyapatite composites.

    PubMed

    Tulinski, Maciej; Jurczyk, Mieczyslaw

    2012-11-01

    In this work Ni-free austenitic stainless steels with nanostructure and their nanocomposites with hydroxyapatite are presented and characterized by means of X-ray diffraction and optical profiling. The samples were synthesized by mechanical alloying, heat treatment and nitriding of elemental microcrystalline powders with addition of hydroxyapatite (HA). In our work we wanted to introduce into stainless steel hydroxyapatite ceramics that have been intensively studied for bone repair and replacement applications. Such applications were chosen because of their high biocompatibility and ability to bond to bone. Since nickel-free austenitic stainless steels seem to have better mechanical properties, corrosion resistance and biocompatibility compared to 316L stainless steels, it is possible that composite made of this steel and HA could improve properties, as well. Mechanical alloying and nitriding are very effective technologies to improve the corrosion resistance of stainless steel. Similar process in case of nanocomposites of stainless steel with hydroxyapatite helps achieve even better mechanical properties and corrosion resistance. Hence nanocrystalline nickel-free stainless steels and nickel-free stainless steel/hydroxyapatite nanocomposites could be promising bionanomaterials for use as a hard tissue replacement implants, e.g., orthopedic implants. In such application, the surface roughness and more specifically the surface topography influences the proliferation of cells (e.g., osteoblasts). PMID:23421285

  10. Production of Oil-in-Water Microspheres Using a Stainless Steel Microchannel.

    PubMed

    Tong, Jihong; Nakajima, Mitsutoshi; Nabetani, Hiroshi; Kikuchi, Yuji; Maruta, Yasuhiro

    2001-05-15

    From the point of view of practical application of the microchannel (MC) emulsification technique, which can be used to produce super-monodispersed microspheres (MS), we fabricated a stainless steel MC and investigated the production and characterization of oil-in-water (O/W) MS using a stainless steel MC instead of a silicon MC plate. We discovered that a stainless steel MC could not be fabricated precisely at a 1-&mgr;m scale; because of its multicrystal property, it can only be processed mechanically on a 10-&mgr;m scale. O/W-MS ranging from 20 to 210 &mgr;m in average diameter were produced using a stainless steel MC with 10 to 80 &mgr;m in equivalent diameter. The MS produced were monodispersed with a coefficient of variation lower than 3% for each individual channel. This value is smaller than that of normal emulsions obtained by the conventional emulsification techniques by 1 order of magnitude. The average diameter of the MS produced at breakthrough pressure was about 2.6 times the stainless steel MC equivalent diameter. The operation pressure affects the MS formation, causing a size-stable zone, size-expanding zone, and outflow zone observed. Larger stainless steel MC demonstrated difficulties in stably producing monodispersed O/W-MS. The breakthrough pressure was approximately inversely proportional to the MC equivalent diameter. Copyright 2001 Academic Press. PMID:11334539

  11. Gas Atomization of Stainless Steel - Slow Motion

    SciTech Connect

    2011-01-01

    Stainless steel liquid atomized by supersonic argon gas into a spray of droplets at ~1800ºC. Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a black and white high speed video of a liquid metal stream being atomized by high pressure gas. This material was atomized at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov

  12. Characterization of silane layers on modified stainless steel surfaces and related stainless steel-plastic hybrids

    NASA Astrophysics Data System (ADS)

    Honkanen, Mari; Hoikkanen, Maija; Vippola, Minnamari; Vuorinen, Jyrki; Lepistö, Toivo; Jussila, Petri; Ali-Löytty, Harri; Lampimäki, Markus; Valden, Mika

    2011-09-01

    The aim of this work was to characterize silane layers on the modified stainless steel surfaces and relate it to the adhesion in the injection-molded thermoplastic urethane-stainless steel hybrids. The silane layers were characterized with scanning electron microscope and transmission electron microscope, allowing the direct quantization of silane layer thickness and its variation. The surface topographies were characterized with atomic force microscope and chemical analyses were performed with X-ray photoelectron spectroscopy. The mechanical strength of the respective stainless steel-thermoplastic urethane hybrids was determined by peel test. Polishing and oxidation treatment of the steel surface improved the silane layer uniformity compared to the industrially pickled surface and increased the adhesion strength of the hybrids, resulting mainly cohesive failure in TPU. XPS analysis indicated that the improved silane bonding to the modified steel surface was due to clean Fe 2O 3-type surface oxide and stronger interaction with TPU was due to more amino species on the silane layer surface compared to the cleaned, industrially pickled surface. Silane layer thickness affected failure type of the hybrids, with a thick silane layer the hybrids failed mainly in the silane layer and with a thinner layer cohesively in plastic.

  13. 78 FR 21417 - Drawn Stainless Steel Sinks From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ..., Washington, DC, and by publishing the notice in the Federal Register on October 22, 2012 (77 FR 64545). The... COMMISSION Drawn Stainless Steel Sinks From China Determinations On the basis of the record \\1\\ developed in... drawn stainless steel sinks from China, provided for in subheading 7324.10.00 of the Harmonized...

  14. 77 FR 23752 - Drawn Stainless Steel Sinks From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-20

    ... the notice in the Federal Register of March 7, 2012 (77 FR 13631). The conference was held in... COMMISSION Drawn Stainless Steel Sinks From China Determinations On the basis of the record \\1\\ developed in... (April 2012), entitled Drawn Stainless Steel Sinks from China: Investigation Nos. 701-TA-489 and...

  15. New Method For Joining Stainless Steel to Titanium

    NASA Technical Reports Server (NTRS)

    Emanuel, W. H.

    1982-01-01

    In new process, edge of stainless-steel sheet is perforated, and joined to titanium by resistance seam welding. Titanium flows into perforations, forming a strong interlocking joint. Process creates a quasi-metallurgical bond between the thin sheets of stainless steel and titanium.

  16. 6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL FABRICATION. STAINLESS STEEL WAS MACHINED IN SIDE A OF THE BUILDING, BEGINNING IN 1957. (4/24/78) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  17. THE CLEANING OF 303 STAINLESS STEEL

    SciTech Connect

    Shen, T H

    2004-04-20

    The sulfur found on the surfaces of stainless steel 303 (SS303) after nitric acid passivation originated from the MnS inclusions in the steel. The nitric acid attacked and dissolved these MnS inclusions, and redeposited micron-sized elemental sulfur particles back to the surface. To develop an alternative passivation procedure for SS303, citric and phosphoric acids have been evaluated. The experimental results show neither acid causes a significant amount of sulfur deposit. Thus, these two acids can be used as alternatives to nitric acid passivation for NIF applications. For SS303 previously passivated by nitric acid, NaOH soak can be used as a remedial cleaning process to effectively remove the sulfur deposits.

  18. Microstructural characterization of the HAZ in AISI 444 ferritic stainless steel welds

    SciTech Connect

    Silva, Cleiton C. Farias, Jesualdo P.; Miranda, Helio C.; Guimaraes, Rodrigo F.; Menezes, John W.A.; Neto, Moises A.M.

    2008-05-15

    Ferritic stainless steel is used as a coating for equipment in the petroleum refining industry. Welding is the main manufacturing and maintenance process used. However, little information on the metallurgical alterations caused by welding of these steels is found in the literature, prompting this study. In this study the authors evaluated the HAZ microstructure of AISI 444 ferritic stainless steel welded plates, by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results indicated that a weld thermal cycle caused microphase precipitation in the HAZ of the ferritic stainless steel. Also needle-like Laves phase precipitation occurred in the HAZ, near the partially-melted zone. Other secondary phases such as chi and sigma were observed, as well as nitride, carbide and carbonitride precipitates.

  19. PORTABLE HYPERSPECTRAL FLUORESCENCE IMAGING SYSTEM FOR DETECTION OF BIOFILM ON STAINLESS STEEL COUPON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Portable hyperspectral fluorescence imaging, as a rapid nondestructive method, was used to investigate detection of bacterial contamination on the surfaces of food processing equipment. In this study, stainless steel plates typically used to manufacture food processing equipment was utilized to gro...

  20. Citric Acid Passivation of Stainless Steel

    NASA Technical Reports Server (NTRS)

    Yasensky, David; Reali, John; Larson, Chris; Carl, Chad

    2009-01-01

    Passivation is a process for cleaning and providing corrosion protection for stainless steel. Currently, on Kennedy Space Center (KSC), only parts passivated with nitric acid are acceptable for use. KSC disposes of approximately 125gal of concentrated nitric acid per year, and receives many parts from vendors who must also dispose of used nitric acid. Unfortunately, nitric acid presents health and environmental hazards. As a result, several recent industry studies have examined citric acid as an alternative. Implementing a citric acid-based passivation procedure would improve the health and environmental safety aspects of passivation process. However although there is a lack of published studies that conclusively prove citric acid is a technically sound passivation agent. In 2007, NASA's KSC Materials Advisory Working Group requested the evaluation of citric acid in place of nitric acid for passivation of parts at KSC. United Space Alliance Materials & Processes engineers have developed a three-phase test plan to evaluate citric acid as an alternative to nitric acid on three stainless steels commonly used at KSC: UNS S30400, S41000, and S17400. Phases 1 and 2 will produce an optimized citric acid treatment based on results from atmospheric exposure at NASA's Beach Corrosion Facility. Phase 3 will compare the optimized solution(s) with nitric acid treatments. If the results indicate that citric acid passivates as well or better than nitric acid, NASA intends to approve this method for parts used at the Kennedy Space Center.

  1. Embrittlement of austenitic stainless steel welds

    SciTech Connect

    David, S.A.; Vitek, J.M.

    1997-12-31

    The microstructure of type-308 austenitic stainless steel weld metal containing {gamma} and {delta} and ferrite is shown. Typical composition of the weld metal is Cr-20.2, Ni-9.4, Mn-1.7, Si-0.5, C-0.05, N-0.06 and balance Fe (in wt %). Exposure of austenitic stainless steel welds to elevated temperatures can lead to extensive changes in the microstructural features of the weld metal. On exposure to elevated temperatures over a long period of time, a continuous network of M{sub 23}C{sub 6} carbide forms at the austenite/ferrite interface. Upon aging at temperatures between 550--850 C, ferrite in the weld has been found to be unstable and transforms to sigma phase. These changes have been found to influence mechanical behavior of the weld metal, in particular the creep-rupture properties. For aging temperatures below 550 C the ferrite decomposes spinodally into {alpha} and {alpha}{prime} phases. In addition, precipitation of G-phase occurs within the decomposed ferrite. These transformations at temperatures below 550 C lead to embrittlement of the weld metal as revealed by the Charpy impact properties.

  2. Antibacterial polyelectrolyte micelles for coating stainless steel.

    PubMed

    Falentin-Daudré, Céline; Faure, Emilie; Svaldo-Lanero, Tiziana; Farina, Fabrice; Jérôme, Christine; Van De Weerdt, Cécile; Martial, Joseph; Duwez, Anne-Sophie; Detrembleur, Christophe

    2012-05-01

    In this study, we report on the original synthesis and characterization of novel antimicrobial coatings for stainless steel by alternating the deposition of aqueous solutions of positively charged polyelectrolyte micelles doped with silver-based nanoparticles with a polyanion. The micelles are formed by electrostatic interaction between two oppositely charged polymers: a polycation bearing 3,4-dihydroxyphenylalanine units (DOPA, a major component of natural adhesives) and a polyanion (poly(styrene sulfonate), PSS) without using any block copolymer. DOPA units are exploited for their well-known ability to anchor to stainless steel and to form and stabilize biocidal silver nanoparticles (Ag(0)). The chlorine counteranion of the polycation forms and stabilizes biocidal silver chloride nanoparticles (AgCl). We demonstrate that two layers of micelles (alternated by PSS) doped with silver particles are enough to impart to the surface strong antibacterial activity against gram-negative E. coli. Moreover, micelles that are reservoirs of biocidal Ag(+) can be easily reactivated after depletion. This novel water-based approach is convenient, simple, and attractive for industrial applications. PMID:22506542

  3. Cast alumina forming austenitic stainless steels

    DOEpatents

    Muralidharan, Govindarajan; Yamamoto, Yukinori; Brady, Michael P

    2013-04-30

    An austenitic stainless steel alloy consisting essentially of, in terms of weight percent ranges 0.15-0.5C; 8-37Ni; 10-25Cr; 2.5-5Al; greater than 0.6, up to 2.5 total of at least one element selected from the group consisting of Nb and Ta; up to 3Mo; up to 3Co; up to 1W; up to 3Cu; up to 15Mn; up to 2Si; up to 0.15B; up to 0.05P; up to 1 total of at least one element selected from the group consisting of Y, La, Ce, Hf, and Zr; <0.3Ti+V; <0.03N; and, balance Fe, where the weight percent Fe is greater than the weight percent Ni, and wherein the alloy forms an external continuous scale comprising alumina, and a stable essentially single phase FCC austenitic matrix microstructure, the austenitic matrix being essentially delta-ferrite free and essentially BCC-phase-free. A method of making austenitic stainless steel alloys is also disclosed.

  4. Attenuation of shock waves in copper and stainless steel

    SciTech Connect

    Harvey, W.B.

    1986-06-01

    By using shock pins, data were gathered on the trajectories of shock waves in stainless steel (SS-304L) and oxygen-free-high-conductivity copper (OFHC-Cu). Shock pressures were generated in these materials by impacting the appropriate target with thin (approx.1.5 mm) flying plates. The flying plates in these experiments were accelerated to high velocities (approx.4 km/s) by high explosives. Six experiments were conducted, three using SS-304L as the target material and three experiments using OFHC-Cu as the target material. Peak shock pressures generated in the steel experiments were approximately 109, 130, and 147 GPa and in the copper experiments, the peak shock pressures were approximately 111, 132, and 143 GPa. In each experiment, an attenuation of the shock wave by a following release wave was clearly observed. An extensive effort using two characteristic codes (described in this work) to theoretically calculate the attenuation of the shock waves was made. The efficacy of several different constitutive equations to successfully model the experiments was studied by comparing the calculated shock trajectories to the experimental data. Based on such comparisons, the conclusion can be drawn that OFHC-Cu enters a melt phase at about 130 GPa on the principal Hugoniot. There was no sign of phase changes in the stainless-steel experiments. In order to match the observed attenuation of the shock waves in the SS-304L experiments, it was necessary to include strength effects in the calculations. It was found that the values for the parameters in the strength equations were dependent on the equation of state used in the modeling of the experiments. 66 refs., 194 figs., 77 tabs.

  5. Dissimilar Friction Stir Welding Between UNS S31603 Austenitic Stainless Steel and UNS S32750 Superduplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Theodoro, Maria Claudia; Pereira, Victor Ferrinho; Mei, Paulo Roberto; Ramirez, Antonio Jose

    2015-02-01

    In order to verify the viability of dissimilar UNS S31603 austenitic and UNS S32750 superduplex stainless steels joined by friction stir welding, 6-mm-thick plates were welded using a PCBN-WRe tool. The welded joints were performed in position control mode at rotational speeds of 100 to 300 rpm and a feed rate of 100 mm/min. The joints performed with 150 and 200 rpm showed good appearance and no defects. The metallographic analysis of both joints showed no internal defects and that the material flow pattern is visible only in the stirred zone (SZ) of the superduplex steel. On the SZ top, these patterns are made of regions of different phases (ferrite and austenite), and on the bottom and central part of the SZ, these patterns are formed by alternated regions of different grain sizes. The ferrite grains in the superduplex steel are larger than those in the austenitic ones along the SZ and thermo-mechanically affected zone, explained by the difference between austenite and ferrite recrystallization kinetics. The amount of ferrite islands present on the austenitic steel base metal decreased near the SZ interface, caused by the dissolving of the ferrite in austenitic matrix. No other phases were found in both joints. The best weld parameters were found to be 200 rpm rotation speed, 100 mm/min feed rate, and tool position control.

  6. Microbial-Influenced Corrosion of Corten Steel Compared with Carbon Steel and Stainless Steel in Oily Wastewater by Pseudomonas aeruginosa

    NASA Astrophysics Data System (ADS)

    Mansouri, Hamidreza; Alavi, Seyed Abolhasan; Fotovat, Meysam

    2015-07-01

    The microbial corrosion behavior of three important steels (carbon steel, stainless steel, and Corten steel) was investigated in semi petroleum medium. This work was done in modified nutrient broth (2 g nutrient broth in 1 L oily wastewater) in the presence of Pseudomonas aeruginosa and mixed culture (as a biotic media) and an abiotic medium for 2 weeks. The behavior of corrosion was analyzed by spectrophotometric and electrochemical methods and at the end was confirmed by scanning electron microscopy. The results show that the degree of corrosion of Corten steel in mixed culture, unlike carbon steel and stainless steel, is less than P. aeruginosa inoculated medium because some bacteria affect Corten steel less than other steels. According to the experiments, carbon steel had less resistance than Corten steel and stainless steel. Furthermore, biofilm inhibits separated particles of those steels to spread to the medium; in other words, particles get trapped between biofilm and steel.

  7. In vivo behavior of a high performance duplex stainless steel.

    PubMed

    Cigada, A; De Santis, G; Gatti, A M; Roos, A; Zaffe, D

    1993-01-01

    An in vivo investigation of a new high molybdenum and nitrogen duplex stainless steel (25Cr--7Ni--4Mo--0.3N) has been performed. Cylindrical pins and specially developed devices, to test in static conditions the in vivo localized corrosion resistance, made of this new duplex steel and of a common austenitic stainless steel were implanted in rabbit's femurs for 6 and 12 months. After sacrifice, SEM observations and EDS microanalyses to detect metallic ion release were carried out on the femur sections surrounding the pins. Morphologic observations with stereoscope and SEM were performed on the metallic surfaces of the special devices in order to detect the presence of localized corrosion. Both ion release and localized corrosion were observed for the specimens made of austenitic stainless steel, but not for those made of 25Cr--7Ni--4Mo--0.3N duplex stainless steel. PMID:10148344

  8. Utility chromium stainless steels in the transportation industry

    SciTech Connect

    Northart, J.F.

    1998-12-31

    The advantages of stainless steel in the Transportation Industry have been well documented over the last two decades. Benefits have been based on fractional maintenance costs, improved operational efficiency, and favorable life cycle cost. The bus and coach industry, as well as rail and trucking industry applications have all exhibited excellent histories utilizing stainless steels. The introduction of the new generation utility ferrilic stainless steels (11%--12% Chromium, or Cr 12) has led to a new and major benefit, which is driving the use of stainless steels in the transportation industry to new heights. Application of these corrosion resistant, utility steels in coal hopper cars, bus underframes, truck bodies and chassis, and even some European car chassis, has reshaped the thinking of those interested in excellent life cycle costing.

  9. A mortality study among mild steel and stainless steel welders.

    PubMed Central

    Moulin, J J; Wild, P; Haguenoer, J M; Faucon, D; De Gaudemaris, R; Mur, J M; Mereau, M; Gary, Y; Toamain, J P; Birembaut, Y

    1993-01-01

    A mortality study was carried out in conjunction with the European mortality study among welders coordinated by the International Agency for Research on Cancer (IARC). The study was aimed at assessing risks for lung cancer in relation to exposure to asbestos, welding fumes containing chromium and nickel, and tobacco smoke. The study included a cohort of 2721 welders and an internal comparison group of 6683 manual workers employed in 13 factories in France. The mortality of the two cohorts was studied from 1975 to 1988 by the historical prospective method. Job histories of welders were traced including welding processes used, metals welded, and proportion of worktime spent in welding. Data on smoking habits were collected from medical records. The observed number of deaths were compared with those expected (standardised mortality ratio (SMR)) based on national rates with adjustments for age, sex, and calendar time. The smoking habits of 87% of the whole study population were known. The distribution of welders and controls according to smoking was not statistically different. The overall mortality was slightly higher for welders (SMR = 1.02, 95% confidence interval (95% CI) 0.89-1.18) than for controls (SMR = 0.91, 95% CI 0.84-0.99). For lung cancer, the SMR was 1.24 (95% CI 0.75-1.94) for welders, whereas the corresponding value was lower for controls (SMR = 0.94, 95% CI 0.68-1.26). The SMR for lung cancer was 1.59 among non-shipyard mild steel welders (95% CI 0.73-3.02). This contrasted with the results for all stainless steel welders (SMR = 0.92, 95% CI 0.19-2.69), and for stainless steel welders predominantly exposed to chromium VI (SMR = 1.03, 95% CI 0.12-3.71). Moreover, SMRs for lung cancer for mild steel welders tended to increase with duration of exposure and time since first exposure, leading to significant excesses for duration > or = 20 years and latency > or = 20 years. Such a pattern was not found for stainless steel welders. PMID:8457490

  10. Stainless Steel Round Robin Test: Centrifugally cast stainless steel screening phase

    SciTech Connect

    Bates, D.J.; Doctor, S.R.; Heasler, P.G.; Burck, E.

    1987-10-01

    This report presents the results of the Centrifugally Cast Stainless Steel Round Robin Test (CCSSRRT). The CCSSRRT is the first phase of an effort to investigate and improve the capability and reliability of NDE inspections of light water reactor piping systems. This phase was a screening test to identify the most promising procedures presently available for CCSS. The next phase will be an in-depth program to evaluate the capability and reliability of inservice inspections (ISI) for piping. In the CCSSRRT, 15 centrifugally cast stainless steel pipe sections containing welds and laboratory-grown thermal fatigue cracks in both columnar and equiaxed base material were used. These pipe specimens were inspected by a total of 18 teams from Europe and the United States using a variety of NDE techniques, mostly ultrasonic (UT). The inspections were carried out at the team's facilities and included inspections from both sides of the weld and inspections restricted to one side of the weld. The results of the CCSSRRT make it apparent that a more detailed study on the capability and reliability of procedures to inspect stainless steel materials is needed to better understand the specific material and flaw properties and how they affect the outcome of an inspection.

  11. Evaluation of Microstructure and Mechanical Properties in Dissimilar Austenitic/Super Duplex Stainless Steel Joint

    NASA Astrophysics Data System (ADS)

    Rahmani, Mehdi; Eghlimi, Abbas; Shamanian, Morteza

    2014-10-01

    To study the effect of chemical composition on microstructural features and mechanical properties of dissimilar joints between super duplex and austenitic stainless steels, welding was attempted by gas tungsten arc welding process with a super duplex (ER2594) and an austenitic (ER309LMo) stainless steel filler metal. While the austenitic weld metal had vermicular delta ferrite within austenitic matrix, super duplex stainless steel was mainly comprised of allotriomorphic grain boundary and Widmanstätten side plate austenite morphologies in the ferrite matrix. Also the heat-affected zone of austenitic base metal comprised of large austenite grains with little amounts of ferrite, whereas a coarse-grained ferritic region was observed in the heat-affected zone of super duplex base metal. Although both welded joints showed acceptable mechanical properties, the hardness and impact strength of the weld metal produced using super duplex filler metal were found to be better than that obtained by austenitic filler metal.

  12. Automatic welding of stainless steel tubing

    NASA Technical Reports Server (NTRS)

    Clautice, W. E.

    1978-01-01

    The use of automatic welding for making girth welds in stainless steel tubing was investigated as well as the reduction in fabrication costs resulting from the elimination of radiographic inspection. Test methodology, materials, and techniques are discussed, and data sheets for individual tests are included. Process variables studied include welding amperes, revolutions per minute, and shielding gas flow. Strip chart recordings, as a definitive method of insuring weld quality, are studied. Test results, determined by both radiographic and visual inspection, are presented and indicate that once optimum welding procedures for specific sizes of tubing are established, and the welding machine operations are certified, then the automatic tube welding process produces good quality welds repeatedly, with a high degree of reliability. Revised specifications for welding tubing using the automatic process and weld visual inspection requirements at the Kennedy Space Center are enumerated.

  13. Radiation resistant austenitic stainless steel alloys

    DOEpatents

    Maziasz, Philip J.; Braski, David N.; Rowcliffe, Arthur F.

    1989-01-01

    An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01% to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties.

  14. Magnetic characterisation of duplex stainless steel

    NASA Astrophysics Data System (ADS)

    Mészáros, I.

    2006-02-01

    Heat treatment-induced microstructural processes were studied by different non-destructive magnetic and mechanical material testing methods in the present work. A commercial SAF 2507 type superduplex stainless steel was investigated. This alloy contains about 40% metastable ferrite which can decompose to a sigma phase and secondary austenite due to heat treatment. All the mechanical, corrosion resistance and magnetic properties are strongly influenced by this microstructural changes. This study had two aims: to understand better the kinetics of the ferrite decomposition process and to study the application possibilities of the applied magnetic measurements. This paper presents an application possibility of the nonlinear harmonics analysis measurement and demonstrates the possibility to find a quantitative correlation between measured harmonics and mechanical properties obtained from destructive tests.

  15. Wear evaluation of high interstitial stainless steel

    SciTech Connect

    Rawers, J.C.; Tylczak, J.H.

    2008-07-01

    A new series of high nitrogen-carbon manganese stainless steel alloys are studied for their wear resistance. High nitrogen and carbon concentrations were obtained by melting elemental iron-chromium-manganese (several with minor alloy additions of nickel, silicon, and molybdenum) in a nitrogen atmosphere and adding elemental graphite. The improvement in material properties (hardness and strength) with increasing nitrogen and carbon interstitial concentration was consistent with previously reported improvements in similar material properties alloyed with nitrogen only. Wear tests included: scratch, pin-on-disk, sand-rubber-wheel, impeller, and jet erosion. Additions of interstitial nitrogen and carbon as well as interstitial nitrogen and carbide precipitates were found to greatly improve material properties. In general, with increasing nitrogen and carbon concentrations, strength, hardness, and wear resistance increased.

  16. Radiation resistant austenitic stainless steel alloys

    DOEpatents

    Maziasz, P.J.; Braski, D.N.; Rowcliffe, A.F.

    1987-02-11

    An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01 to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties. 4 figs.

  17. Automatic Welding of Stainless Steel Tubing

    NASA Technical Reports Server (NTRS)

    Clautice, W. E.

    1978-01-01

    To determine if the use of automatic welding would allow reduction of the radiographic inspection requirement, and thereby reduce fabrication costs, a series of welding tests were performed. In these tests an automatic welder was used on stainless steel tubing of 1/2, 3/4, and 1/2 inch diameter size. The optimum parameters were investigated to determine how much variation from optimum in machine settings could be tolerate and still result in a good quality weld. The process variables studied were the welding amperes, the revolutions per minute as a function of the circumferential weld travel speed, and the shielding gas flow. The investigation showed that the close control of process variables in conjunction with a thorough visual inspection of welds can be relied upon as an acceptable quality assurance procedure, thus permitting the radiographic inspection to be reduced by a large percentage when using the automatic process.

  18. MOCVD deposition of YSZ on stainless steels

    NASA Astrophysics Data System (ADS)

    Chevalier, S.; Kilo, M.; Borchardt, G.; Larpin, J. P.

    2003-01-01

    Yttria stabilized zirconia was deposited on stainless steel using the metal-organic chemical vapor deposition (MOCVD) technique, from β-diketonate precursors. The variation of the evaporation temperatures of yttrium and zirconium precursor allowed to control the level of Y within the film. Over the temperature range 125-150 °C, the Y content increased from 2.5 to 17.6 at.%. X-ray diffraction (XRD) analyses evidenced tetragonal phase of zirconia when the Y content was below 8 at.%, and cubic phase for higher concentration. Sputtered neutral mass spectrometry (SNMS) profiles confirmed that the control and stability of Y precursor temperature were of major importance to guarantee the homogeneity of the deposited films.

  19. Hydrogen vibrations in austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Danilkin, S. A.; Delafosse, D.; Fuess, H.; Gavriljuk, V. G.; Ivanov, A.; Magnin, T.; Wipf, H.

    The vibrational modes of hydrogen in fcc Fe-25Cr-20Ni stainless steel with a hydrogen content of 0.33at.% were studied by neutron spectroscopy. Hydrogen doping was performed at 810K in a hydrogen-gas atmosphere of 190bar. Neutron spectra were taken at 2K and 77K with the spectrometer IN1-BeF (ILL, Grenoble). The spectra show the fundamental hydrogen vibration at 130 meV and the second harmonics at 260 meV. The frequencies are higher than in other fcc hydrides. In spite of the cubic symmetry of the octahedral hydrogen positions and the low hydrogen content, the inelastic hydrogen peak has a relatively large width and an asymmetric shape.

  20. Materials compatibility of hydride storage materials with austenitic stainless steels

    SciTech Connect

    Clark, E.A.

    1992-09-21

    This task evaluated the materials compatibility of LaNi[sub 5-x]Al[sub x] (x= 0.3, 0.75) hydrides and palladium coated kieselguhr with austenitic stainless steel in hydrogen and tritium process environments. Based on observations of retired prototype hydride storage beds and materials exposure testing samples designed for this study, no materials compatibility problem was indicated. Scanning electron microscopy observations of features on stainless steel surfaces after exposure to hydrides are also commonly found on as-received materials before hydriding. These features are caused by either normal heat treating and acid cleaning of stainless steel or reflect the final machining operation.

  1. Materials compatibility of hydride storage materials with austenitic stainless steels

    SciTech Connect

    Clark, E.A.

    1992-09-21

    This task evaluated the materials compatibility of LaNi{sub 5-x}Al{sub x} (x= 0.3, 0.75) hydrides and palladium coated kieselguhr with austenitic stainless steel in hydrogen and tritium process environments. Based on observations of retired prototype hydride storage beds and materials exposure testing samples designed for this study, no materials compatibility problem was indicated. Scanning electron microscopy observations of features on stainless steel surfaces after exposure to hydrides are also commonly found on as-received materials before hydriding. These features are caused by either normal heat treating and acid cleaning of stainless steel or reflect the final machining operation.

  2. Materials compatibility of hydride storage materials with austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Clark, E. A.

    1992-09-01

    This task evaluated the materials compatibility of LaNi(5-x)Al(x) (x= 0.3, 0.75) hydrides and palladium coated kieselguhr with austenitic stainless steel in hydrogen and tritium process environments. Based on observations of retired prototype hydride storage beds and materials exposure testing samples designed for this study, no materials compatibility problem was indicated. Scanning electron microscopy observations of features on stainless steel surfaces after exposure to hydrides are also commonly found on as-received materials before hydriding. These features are caused by either normal heat treating and acid cleaning of stainless steel or reflect the final machining operation.

  3. A preliminary ferritic-martensitic stainless steel constitution diagram

    SciTech Connect

    Balmforth, M.C.; Lippold, J.C.

    1998-01-01

    This paper describes preliminary research to develop a constitution diagram that will more accurately predict the microstructure of ferritic and martensitic stainless steel weld deposits. A button melting technique was used to produce a wide range of compositions using mixtures of conventional ferritic and martensitic stainless steels, including types 403, 409, 410, 430, 439 and 444. These samples were prepared metallographically, and the vol-% ferrite and martensite was determined quantitatively. In addition, the hardness and ferrite number (FN) were measured. Using this data, a preliminary constitution diagram is proposed that provides a more accurate method for predicting the microstructures of arc welds in ferritic and martensitic stainless steels.

  4. Stainless steel-zirconium alloy waste forms

    SciTech Connect

    McDeavitt, S.M.; Abraham, D.P.; Keiser, D.D. Jr.; Park, J.Y.

    1996-07-01

    An electrometallurgical treatment process has been developed by Argonne National Laboratory to convert various types of spent nuclear fuels into stable storage forms and waste forms for repository disposal. The first application of this process will be to treat spent fuel alloys from the Experimental Breeder Reactor-II. Three distinct product streams emanate from the electrorefining process: (1) refined uranium; (2) fission products and actinides extracted from the electrolyte salt that are processed into a mineral waste form; and (3) metallic wastes left behind at the completion of the electrorefining step. The third product stream (i.e., the metal waste stream) is the subject of this paper. The metal waste stream contains components of the chopped spent fuel that are unaffected by the electrorefining process because of their electrochemically ``noble`` nature; this includes the cladding hulls, noble metal fission products (NMFP), and, in specific cases, zirconium from metal fuel alloys. The selected method for the consolidation and stabilization of the metal waste stream is melting and casting into a uniform, corrosion-resistant alloy. The waste form casting process will be carried out in a controlled-atmosphere furnace at high temperatures with a molten salt flux. Spent fuels with both stainless steel and Zircaloy cladding are being evaluated for treatment; thus, stainless steel-rich and Zircaloy-rich waste forms are being developed. Although the primary disposition option for the actinides is the mineral waste form, the concept of incorporating the TRU-bearing product into the metal waste form has enough potential to warrant investigation.

  5. Standard specification for pressure vessel plates, carbon steel, high strength, for moderate and lower temperature service. ASTM standard

    SciTech Connect

    1998-12-01

    This specification is under the jurisdiction of ASTM Committee A-1 on Steel, Stainless Steel, and Related Alloys and is the responsibility of Subcommittee A01.11 on Steel Plates for Boilers and Pressure Vessels. Current edition approved Sep. 10, 1998. Published December 1998. Originally published as A 612-70. Last previous edition A 612/A 612M-90(1996).

  6. Stainless steel anodes for alkaline water electrolysis and methods of making

    DOEpatents

    Soloveichik, Grigorii Lev

    2014-01-21

    The corrosion resistance of stainless steel anodes for use in alkaline water electrolysis was increased by immersion of the stainless steel anode into a caustic solution prior to electrolysis. Also disclosed herein are electrolyzers employing the so-treated stainless steel anodes. The pre-treatment process provides a stainless steel anode that has a higher corrosion resistance than an untreated stainless steel anode of the same composition.

  7. Bacterial adhesion on ion-implanted stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Zhao, Q.; Liu, Y.; Wang, C.; Wang, S.; Peng, N.; Jeynes, C.

    2007-08-01

    Stainless steel disks were implanted with N +, O + and SiF 3+, respectively at the Surrey Ion Beam Centre. The surface properties of the implanted surfaces were analyzed, including surface chemical composition, surface topography, surface roughness and surface free energy. Bacterial adhesion of Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus aureus, which frequently cause medical device-associated infections was evaluated under static condition and laminar flow condition. The effect of contact time, growth media and surface properties of the ion-implanted steels on bacterial adhesion was investigated. The experimental results showed that SiF 3+-implanted stainless steel performed much better than N +-implanted steel, O +-implanted steel and untreated stainless steel control on reducing bacterial attachment under identical experimental conditions.

  8. Phase transformations in cast duplex stainless steels

    NASA Astrophysics Data System (ADS)

    Kim, Yoon-Jun

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as sigma (sigma) and chi (chi) can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase (sigma + chi) formation were analyzed using the Johnson-Mehl-Avrami (JMA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities, a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, a was stabilized with increasing Cr addition and chi by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in

  9. Phase Transformations in Cast Duplex Stainless Steels

    SciTech Connect

    Yoon-Jun Kim

    2004-12-19

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as {sigma} and {chi} can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase ({sigma} + {chi}) formation were analyzed using the Johnson-Mehl-Avrami (MA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities; a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, {sigma} was stabilized with increasing Cr addition and {chi} by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in

  10. Liquid Metal Corrosion of 316L Stainless Steel, 410 Stainless Steel, and 1015 Carbon Steel in a Molten Zinc Bath

    NASA Astrophysics Data System (ADS)

    Xu, Jing; Bright, Mark A.; Liu, Xingbo; Barbero, Ever

    2007-11-01

    Corrosion tests of 1015 low-carbon steel and two stainless steels (410 and 316L) were conducted in a pure zinc bath (99.98 wt pct Zn) in order to better understand the reaction mechanisms that occur during the degradation of submerged hardware at industrial general (batch) galvanizing operations. Through this testing, it was found that, in general, 316L stainless steel showed the best dissolution resistance among these three alloys, while 1015 carbon steel provided a lower solubility than 410 stainless steel. Investigating the failure mechanisms, both metallurgical composition and lattice structure played important roles in the molten metal corrosion behaviors of these alloys. High contents of nickel combined with the influence of chromium improved the resistance to molten zinc corrosion. Moreover, a face-centered-cubic (fcc) structure was more corrosion resistant than body-centered-cubic (bcc) possibly due to the compactness of the atomic structure. Analogously, the body-centered-tetragonal (bct) martensite lattice structure possessed enhanced susceptibility to zinc corrosion as a result of the greater atomic spacing and high strain energy. Finally, an increased bath temperature played an important role in molten metal corrosion by accelerating the dissolution process and changing the nature of intermetallic layers.

  11. Ultrasonics permits brazing complex stainless steel assembly without flux

    NASA Technical Reports Server (NTRS)

    Baker, W. H.

    1967-01-01

    Ultrasonic vibration of an assembly of stainless steel instrumentation tubes ensures brazing without flux. Vibration with an ultrasonic transducer permits the brazing material to flow down each tube in contact with a seal plug installed in a pressure vessel wall.

  12. Stainless-steel elbows formed by spin forging

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Large seamless austenitic stainless steel elbows are fabricated by spin forging /rotary shear forming/. A specially designed spin forging tool for mounting on a hydrospin machine has been built for this purpose.

  13. Stress corrosion cracking evaluation of precipitation-hardening stainless steel

    NASA Technical Reports Server (NTRS)

    Humphries, T. S.; Nelson, E. E.

    1970-01-01

    Accelerated test program results show which precipitation hardening stainless steels are resistant to stress corrosion cracking. In certain cases stress corrosion susceptibility was found to be associated with the process procedure.

  14. Cavitation erosion of duplex and super duplex stainless steels

    SciTech Connect

    Kwok, C.T.; Man, H.C.; Cheng, F.T.

    1998-10-05

    Owing to their excellent corrosion resistance, stainless steels are widely used both in the marine, urban water, chemical and food industries. In addition to the corrosive environment, high fluid flow speeds are always encountered for components used in these industries. The cavitation characteristics of S30400 and S31600 austenitic stainless steels and duplex stainless steels were studied in detail by a number of authors. It was generally agreed that S30400 has higher cavitation erosion resistance than that of S31600 due to higher tendency of strain induced martensitic transformation under high impulse of stress. A considerable number of results on stress corrosion cracking characteristics of SDSS and duplex stainless steels have been published but data concerning their cavitation erosion property are extremely rare.

  15. Stress-Corrosion Cracking in Martensitic PH Stainless Steels

    NASA Technical Reports Server (NTRS)

    Humphries, T.; Nelson, E.

    1984-01-01

    Precipitation-hardening alloys evaluated in marine environment tests. Report describes marine-environment stress-corrosion cracking (SCC) tests of three martensitic precipitation hardening (PH) stainless-steel alloys.

  16. 27. STAINLESS STEEL FERMENTING CASKS MADE BY ZERO MANG OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. STAINLESS STEEL FERMENTING CASKS MADE BY ZERO MANG OF WASHINGTON, MISSOURI. VIEW LOOKING NORTH TOWARD VAULT OF THE TWELVE APOSTLES - Stone Hill Winery, 401 West Twelfth Street, Hermann, Gasconade County, MO

  17. Nafion coated stainless steel for anti-biofilm application.

    PubMed

    Zhong, Li Juan; Pang, Li Qing; Che, Li Ming; Wu, Xue E; Chen, Xiao Dong

    2013-11-01

    Biofilms can adhere to most surfaces and have caused a wide range of problems in various industrial processes as well as daily life activities. In this work, the anti-biofilm ability of Nafion-coated stainless steel surface was investigated and our results showed that stainless steel discs coated with 1% Nafion can significantly reduce E. coli adhesion. Nafion has a large amount of negatively charged sulphonate groups, and the findings of this study suggest that the negative surface charge can greatly reduce bacterial adhesion through increasing the electrostatic repulsion between negatively charged bacterial cells and Nafion coated stainless steel surface. The roughness of coated and uncoated stainless steel discs made no significant differences while the hydrophobic of the discs increased after coated with Nafion. PMID:23831592

  18. Hafnium stainless steel absorber rod for control rod

    SciTech Connect

    Charnley, J.E.; Cearley, J.E.; Dixon, R.C.; Izzo, K.R.; Aiello, L.L.

    1989-08-01

    This patent describes an improvement in a control rod having a stainless steel body for enclosing a neutron absorbing poison, the control rod having movement along an axial direction for insertion into and out of a nuclear reactor for controlling a nuclear reaction. The improvement comprising: a piece of hafnium; a piece of stainless steel joined to the hafnium by a thin diffusion interface created by friction welding. The hafnium and the stainless steel oriented serially in the axial direction with the thin diffusion interface disposed normal to the axial direction of the control rod movement; means for confining the hafnium to movement along the axial direction with the control rod; and means for attaching the piece of stainless steel to the remaining portion of the control rod to load the weld therebetween under compression or tension during the control rod movement. Whereby the thin diffusion interface is loaded in tension or compression only upon dynamic movement of the control rod.

  19. Eddy sensors for small diameter stainless steel tubes.

    SciTech Connect

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  20. Welding stainless steels for structures operating at liquid helium temperature

    SciTech Connect

    Witherell, C.E.

    1980-04-18

    Superconducting magnets for fusion energy reactors require massive monolithic stainless steel weldments which must operate at extremely low temperatures under stresses approaching 100 ksi (700 MPa). A three-year study was conducted to determine the feasibility of producing heavy-section welds having usable levels of strength and toughness at 4.2/sup 0/K for fabrication of these structures in Type 304LN plate. Seven welding processes were evaluated. Test weldments in full-thickness plate were made under severe restraint to simulate that of actual structures. Type 316L filler metal was used for most welds. Welds deposited under some conditions and which solidify as primary austenite have exhibited intergranular embrittlement at 4.2/sup 0/K. This is believed to be associated with grain boundary metal carbides or carbonitrides precipitated during reheating of already deposited beads by subsequent passes. Weld deposits which solidify as primary delta ferrite appear immune. Through use of fully austenitic filler metals of low nitrogen content under controlled shielded metal arc welding conditions, and through use of filler metals solidifying as primary delta ferrite where only minimum residuals remain to room temperature, welds of Type 316L composition have been made with 4.2K yield strength matching that of Type 304LN plate and acceptable levels of soundness, ductility and toughness.

  1. 77 FR 64545 - Drawn Stainless Steel Sinks From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-22

    ... respect to electronic filing have been amended. The amendments took effect on November 7, 2011. See 76 FR... COMMISSION Drawn Stainless Steel Sinks From China Scheduling of the final phase of countervailing duty and... retarded, by reason of subsidized and less-than-fair-value imports from China of drawn stainless...

  2. Measurement of intergranular attack in stainless steel using ultrasonic energy

    DOEpatents

    Mott, Gerry; Attaar, Mustan; Rishel, Rick D.

    1989-08-08

    Ultrasonic test methods are used to measure the depth of intergranular attack (IGA) in a stainless steel specimen. The ultrasonic test methods include a pitch-catch surface wave technique and a through-wall pulse-echo technique. When used in combination, these techniques can establish the extent of IGA on both the front and back surfaces of a stainless steel specimen from measurements made on only one surface.

  3. Probing the duplex stainless steel phases via magnetic force microscopy

    NASA Astrophysics Data System (ADS)

    Gheno, S. M.; Santos, F. S.; Kuri, S. E.

    2008-03-01

    Duplex stainless steels are austenitic-ferritic alloys used in many applications, thanks to their excellent mechanical properties and high corrosion resistance. In this work, chemical analyses, x-ray diffraction, and magnetic force microscopy (MFM) were employed to characterize the solution annealed and aged duplex stainless steel. The samples exhibited no changes in lattice parameters and the MFM technique proved successful in clearly imaging the magnetic domain structure of the ferrite phase.

  4. Procedure for flaw detection in cast stainless steel

    DOEpatents

    Kupperman, David S.

    1988-01-01

    A method of ultrasonic flaw detection in cast stainless steel components incorporating the steps of determining the nature of the microstructure of the cast stainless steel at the site of the flaw detection measurements by ultrasonic elements independent of the component thickness at the site; choosing from a plurality of flaw detection techniques, one such technique appropriate to the nature of the microstructure as determined and detecting flaws by use of the chosen technique.

  5. Solidification behavior of austenitic stainless steel filler metals

    SciTech Connect

    David, S.A.; Goodwin, G.M.; Braski, D.N.

    1980-02-01

    Thermal analysis and interrupted solidification experiments on selected austenitic stainless steel filler metals provided an understanding of the solidification behavior of austenitic stainless steel welds. The sequences of phase separations found were for type 308 stainless steel filler metal, L + L + delta + L + delta + ..gamma.. ..-->.. ..gamma.. + delta, and for type 310 stainless steel filler metal, L ..-->.. L + ..gamma.. ..-->.. ..gamma... In type 308 stainless steel filler metal, ferrite at room temperature was identified as either the untransformed primary delta-ferrite formed during the initial stages of solidification or the residual ferrite after Widmanstaetten austenite precipitation. Microprobe and scanning transmission electron microscope microanalyses revealed that solute extensively redistributes during the transformation of primary delta-ferrite to austenite, leading to enrichment and stabilization of ferrite by chromium. The type 310 stainless steel filler metal investigated solidifies by the primary crystallization of austenite, with the transformation going to completion at the solidus temperature. In our samples residual ferrite resulting from solute segregation was absent at the intercellular or interdendritic regions.

  6. X-ray attenuation properties of stainless steel (u)

    SciTech Connect

    Wang, Lily L; Berry, Phillip C

    2009-01-01

    Stainless steel vessels are used to enclose solid materials for studying x-ray radiolysis that involves gas release from the materials. Commercially available stainless steel components are easily adapted to form a static or a dynamic condition to monitor the gas evolved from the solid materials during and after the x-ray irradiation. Experimental data published on the x-ray attenuation properties of stainless steel, however, are very scarce, especially over a wide range of x-ray energies. The objective of this work was to obtain experimental data that will be used to determine how a poly-energetic x-ray beam is attenuated by the stainless steel container wall. The data will also be used in conjunction with MCNP (Monte Carlos Nuclear Particle) modeling to develop an accurate method for determining energy absorbed in known solid samples contained in stainless steel vessels. In this study, experiments to measure the attenuation properties of stainless steel were performed for a range of bremsstrahlung x-ray beams with a maximum energy ranging from 150 keV to 10 MeV. Bremsstrahlung x-ray beams of these energies are commonly used in radiography of engineering and weapon components. The weapon surveillance community has a great interest in understanding how the x-rays in radiography affect short-term and long-term properties of weapon materials.

  7. Hybrid Laser-arc Welding of 17-4 PH Martensitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Ma, Junjie; Atabaki, Mehdi Mazar; Pillai, Raju; Kumar, Biju; Vasudevan, Unnikrishnan; Sreshta, Harold; Kovacevic, Radovan

    2015-06-01

    17-4 PH stainless steel has wide applications in severe working conditions due to its combination of good corrosion resistance and high strength. The weldability of 17-4 PH stainless steel is challenging. In this work, hybrid laser-arc welding was developed to weld 17-4 PH stainless steel. This method was chosen based on its advantages, such as deep weld penetration, less filler materials, and high welding speed. The 17-4 PH stainless steel plates with a thickness of 19 mm were successfully welded in a single pass. During the hybrid welding, the 17-4 PH stainless steel was immensely susceptible to porosity and solidification cracking. The porosity was avoided by using nitrogen as the shielding gas. The nitrogen stabilized the keyhole and inhibited the formation of bubbles during welding. Solidification cracking easily occurred along the weld centerline at the root of the hybrid laser-arc welds. The microstructural evolution and the cracking susceptibility of 17-4 PH stainless steel were investigated to remove these centerline cracks. The results showed that the solidification mode of the material changed due to high cooling rate at the root of the weld. The rapid cooling rate caused the transformation from ferrite to austenite during the solidification stage. The solidification cracking was likely formed as a result of this cracking-susceptible microstructure and a high depth/width ratio that led to a high tensile stress concentration. Furthermore, the solidification cracking was prevented by preheating the base metal. It was found that the preheating slowed the cooling rate at the root of the weld, and the ferrite-to-austenite transformation during the solidification stage was suppressed. Delta ferrite formation was observed in the weld bead as well no solidification cracking occurred by optimizing the preheating temperature.

  8. Fabrication of stainless steel clad tubing. [gas pressure bonding

    NASA Technical Reports Server (NTRS)

    Kovach, C. W.

    1978-01-01

    The feasibility of producing stainless steel clad carbon steel tubing by a gas pressure bonding process was evaluated. Such a tube product could provide substantial chromium savings over monolithic stainless tubing in the event of a serious chromium shortage. The process consists of the initial assembly of three component tubesets from conventionally produced tubing, the formation of a strong metallurgical bond between the three components by gas pressure bonding, and conventional cold draw and anneal processing to final size. The quality of the tubes produced was excellent from the standpoint of bond strength, mechanical, and forming properties. The only significant quality problem encountered was carburization of the stainless clad by the carbon steel core which can be overcome by further refinement through at least three different approaches. The estimated cost of clad tubing produced by this process is greater than that for monolithic stainless tubing, but not so high as to make the process impractical as a chromium conservation method.

  9. Austenitic stainless steel for high temperature applications

    DOEpatents

    Johnson, Gerald D.; Powell, Roger W.

    1985-01-01

    This invention describes a composition for an austenitic stainless steel which has been found to exhibit improved high temperature stress rupture properties. The composition of this alloy is about (in wt. %): 12.5 to 14.5 Cr; 14.5 to 16.5 Ni; 1.5 to 2.5 Mo; 1.5 to 2.5 Mn; 0.1 to 0.4 Ti; 0.02 to 0.08 C; 0.5 to 1.0 Si; 0.01 maximum, N; 0.02 to 0.08 P; 0.002 to 0.008 B; 0.004-0.010 S; 0.02-0.05 Nb; 0.01-0.05 V; 0.005-0.02 Ta; 0.02-0.05 Al; 0.01-0.04 Cu; 0.02-0.05 Co; 0.03 maximum, As; 0.01 maximum, O; 0.01 maximum, Zr; and with the balance of the alloy being essentially iron. The carbon content of the alloy is adjusted such that wt. % Ti/(wt. % C+wt. % N) is between 4 and 6, and most preferably about 5. In addition the sum of the wt. % P+wt. % B+wt. % S is at least 0.03 wt. %. This alloy is believed to be particularly well suited for use as fast breeder reactor fuel element cladding.

  10. Weldable, age hardenable, austenitic stainless steel

    DOEpatents

    Brooks, J.A.; Krenzer, R.W.

    1975-07-22

    An age hardenable, austenitic stainless steel having superior weldability properties as well as resistance to degradation of properties in a hydrogen atmosphere is described. It has a composition of from about 24.0 to about 34.0 weight percent (w/o) nickel, from about 13.5 to about 16.0 w/o chromium, from about 1.9 to about 2.3 w/o titanium, from about 1.0 to about 1.5 w/ o molybdenum, from about 0.01 to about 0.05 w/o carbon, from about 0 to about 0.25 w/o manganese, from about 0 to about 0.01 w/o phosphorous and preferably about 0.005 w/o maximum, from about 0 to about 0.010 w/o sulfur and preferably about 0.005 w/o maximum, from about 0 to about 0.25 w/o silicon, from about 0.1 to about 0.35 w/o aluminum, from about 0.10 to about 0.50 w/o vanadium, from about 0 to about 0.0015 w/o boron, and the balance essentially iron. (auth)

  11. New Economical 19Cr Duplex Stainless Steels

    NASA Astrophysics Data System (ADS)

    Li, Jun; Zhang, Zixing; Chen, Hong; Xiao, Xueshan; Zhao, Junliang; Jiang, Laizhu

    2012-02-01

    New economical duplex stainless steels (DSSs) containing 19Cr-6Mn- xNi-1.0Mo-0.5W-0.5Cu-0.2N ( x = 0.5 to 2.0) were developed, and the microstructure, impact property, and corrosion resistance of the alloys were studied. The ferrite content increases with the solution treatment temperature, but decreases with an increase in nickel. The sigma phase is not found precipitating in the alloys treated with solution from 1023 K to 1523 K (750 °C to 1250 °C). The low-temperature impact energy of the experimental alloys increases first and then decreases rapidly with an increase in nickel, which is mainly due to the martensite transformation with an increase in austenite. The alloys have a better mechanical property and pitting corrosion resistance than AISI 304. Among the designed DSS alloys, 19Cr-6Mn-1.3Ni-1.0Mo-0.5W-0.5Cu-0.2N is found to be an optimum alloy with proper phase proportion, a better combination of mechanical strength and elongation, and higher pitting corrosion resistance compared with those of the other alloys.

  12. NanoComposite Stainless Steel Powder Technologies

    SciTech Connect

    DeHoff, R.; Glasgow, C.

    2012-07-25

    Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.

  13. Weldability of neutron irradiated austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Asano, Kyoichi; Nishimura, Seiji; Saito, Yoshiaki; Sakamoto, Hiroshi; Yamada, Yuji; Kato, Takahiko; Hashimoto, Tsuneyuki

    1999-01-01

    Degradation of weldability in neutron irradiated austenitic stainless steel is an important issue to be addressed in the planning of proactive maintenance of light water reactor core internals. In this work, samples selected from reactor internal components which had been irradiated to fluence from 8.5 × 10 22 to 1.4 × 10 26 n/m 2 ( E > 1 MeV) corresponding to helium content from 0.11 to 103 appm, respectively, were subjected to tungsten inert gas arc (TIG) welding with heat input ranged 0.6-16 kJ/cm. The weld defects were characterized by penetrant test and cross-sectional metallography. The integrity of the weld was better when there were less helium and at lower heat input. Tensile properties of weld joint containing 0.6 appm of helium fulfilled the requirement for unirradiated base metal. Repeated thermal cycles were found to be very hazardous. The results showed the combination of material helium content and weld heat input where materials can be welded with little concern to invite cracking. Also, the importance of using properly selected welding procedures to minimize thermal cycling was recognized.

  14. Welding Behavior of Free Machining Stainless Steel

    SciTech Connect

    BROOKS,JOHN A.; ROBINO,CHARLES V.; HEADLEY,THOMAS J.; MICHAEL,JOSEPH R.

    2000-07-24

    The weld solidification and cracking behavior of sulfur bearing free machining austenitic stainless steel was investigated for both gas-tungsten arc (GTA) and pulsed laser beam weld processes. The GTA weld solidification was consistent with those predicted with existing solidification diagrams and the cracking response was controlled primarily by solidification mode. The solidification behavior of the pulsed laser welds was complex, and often contained regions of primary ferrite and primary austenite solidification, although in all cases the welds were found to be completely austenite at room temperature. Electron backscattered diffraction (EBSD) pattern analysis indicated that the nature of the base metal at the time of solidification plays a primary role in initial solidification. The solid state transformation of austenite to ferrite at the fusion zone boundary, and ferrite to austenite on cooling may both be massive in nature. A range of alloy compositions that exhibited good resistance to solidification cracking and was compatible with both welding processes was identified. The compositional range is bounded by laser weldability at lower Cr{sub eq}/Ni{sub eq} ratios and by the GTA weldability at higher ratios. It was found with both processes that the limiting ratios were somewhat dependent upon sulfur content.

  15. Weldability Comparison of Tritium-Charged-and -Aged 304 and 316LN Stainless Steels

    SciTech Connect

    Tosten, M.H.

    2003-06-10

    Measurement of the effects of helium (from tritium decay) on the weldability of Types 304 and ITER Grade 316LN stainless steel demonstrated the inherent complexities in designing and conducting an experimental program using tritium-charged-and-aged materials to simulate the effects of irradiation-induced helium on weld behavior. Differences in microstructure, surface condition and alloy chemistry are known to play key roles in tritium absorption and distribution and thus have direct effects on the subsequent 3He production and distribution. The helium embrittlement cracking produced in 0.5 in. (12.7 mm) thick 304 and 316LN plates that were tritium-charged in the same container and subsequently welded with gas metal arc, low heat input weld overlays and gas tungsten arc stringer beads, varied markedly. For example, the porosity in the weld beads was much higher in the 304 plate than in the 316LN plate. Additionally, crack measurements from weld cross-sections revealed more extensive intergranular cracking in the heat-affected zones of welds on the 304 plate when compared to the 316LN plate. However, the differences between the two types of stainless steel may not be a result of differences in the resistance to helium embrittlement cracking, but may be due to initial tritium concentration differences developed in the as-charged plates. Further work is necessary to identify the reasons for the apparent plate to plate variation in tritium/helium content and to demonstrate the similarities (or differences) between Types 304 and ITER grade 316LN stainless steel.

  16. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  17. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  18. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  19. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  20. Investigation of the diffusion kinetics of borided stainless steels

    NASA Astrophysics Data System (ADS)

    Kayali, Yusuf

    2013-12-01

    In this study, the kinetics of borides formed on AISI 420, AISI 304 and AISI 304L stainless steels was investigated. Boronizing treatment was carried out using Ekabor-II powders at the processing temperatures of 1123, 1173 and 1223 K for 2, 4 and 6 h. The phases of the boride layers of borided AISI 420, AISI 304 and AISI 304L stainless steels were FeB, Fe2B, CrB and NiB, respectively. The thickness of the boride layer formed on the borided steels ranged from 4.6 to 64 μm depending on the boriding temperature, boriding time and alloying elements of the stainless steels. Depending on the chemical composition, temperature and layer thickness, the activation energies of boron in AISI 420, AISI 304 and AISI 304L stainless steels were found to be 206.161, 234.641 and 222.818 kJ/mol, respectively. The kinetics of growth of the boride layers formed on the AISI 420, AISI 304 and AISI 304L stainless steels and the thickness of the boride layers were investigated.

  1. Stainless steel tube-based cell cryopreservation containers.

    PubMed

    Shih, Wei-Hung; Yu, Zong-Yan; Wu, Wei-Te

    2013-12-01

    This study focused on increasing the freezing rate in cell vitrification cryopreservation by using a cryopreservation container possessing rigid mechanical properties and high heat-transfer efficiency. Applying a fast freezing rate in vitrification cryopreservation causes a rapid temperature change in the cryopreservation container and has a substantial impact on mechanical properties; therefore, a highly rigid cryopreservation container that possesses a fast freezing rate must be developed. To produce a highly rigid cryopreservation container possessing superior heat transfer efficiency, this study applies an electrochemical machining (ECM) method to an ANSI 316L stainless steel tube to treat the surface material by polishing and roughening, thereby increasing the freezing rate and reducing the probability of ice crystal formation. The results indicated that the ECM method provided high-quality surface treatment of the stainless steel tube. This method can reduce internal surface roughness in the stainless steel tube, thereby reducing the probability of ice crystal formation, and increase external surface roughness, consequently raising convection heat-transfer efficiency. In addition, by thinning the stainless steel tube, this method reduces heat capacity and thermal resistance, thereby increasing the freezing rate. The freezing rate (3399 ± 197 °C/min) of a stainless steel tube after interior and exterior polishing and exterior etching by applying ECM compared with the freezing rate (1818 ± 54 °C/min) of an original stainless steel tube was increased by 87%, which also exceeds the freezing rate (2015 ± 49 °C/min) of an original quartz tube that has a 20% lower heat capacity. However, the results indicated that increasing heat-transferring surface areas and reducing heat capacities cannot effectively increase the freezing rate of a stainless steel tube if only one method is applied; instead, both techniques must be implemented concurrently to improve the

  2. Ultrasonic guided wave detection of scatterers on large clad steel plates

    NASA Astrophysics Data System (ADS)

    Gong, Peng; Harley, Joel B.; Berges, Mario; Junker, Warren R.; Greve, David W.; Oppenheim, Irving J.

    2016-04-01

    "Clad steel" refers to a thick carbon steel structural plate bonded to a corrosion resistant alloy (CRA) plate, such as stainless steel or titanium, and is widely used in industry to construct pressure vessels. The CRA resists the chemically aggressive environment on the interior, but cannot prevent the development of corrosion losses and cracks that limit the continued safe operation of such vessels. At present there are no practical methods to detect such defects from the exposed outer surface of the thick carbon steel plate, often necessitating removing such vessels from service and inspecting them visually from the interior. In previous research, sponsored by industry to detect and localize damage in pressurized piping systems under operational and environmental changes, we investigated a number of data-driven signal processing methods to extract damage information from ultrasonic guided wave pitch-catch records. We now apply those methods to relatively large clad steel plate specimens. We study a sparse array of wafer-type ultrasonic transducers adhered to the carbon steel surface, attempting to localize mass scatterers grease-coupled to the stainless steel surface. We discuss conditions under which localization is achieved by relatively simple first-arrival methods, and other conditions for which data-driven methods are needed; we also discuss observations of plate-like mode properties implied by these results.

  3. Corrosion in lithium-stainless steel thermal-convection systems

    SciTech Connect

    Tortorelli, P.F.; DeVan, J.H.; Selle, J.E.

    1980-01-01

    The corrosion of types 304L and 316 austenitic stainless steel by flowing lithium was studied in thermal-convection loops operated at 500 to 650/sup 0/C. Both weight and compositional changes were measured on specimens distributed throughout each loop and were combined with metallographic examinations to evaluate the corrosion processes. The corrosion rate and mass transfer characteristics did not significantly differ between the two austenitic stainless steels. Addition of 500 or 1700 wt ppM N to purified lithium did not increase the dissolution rate or change the attack mode of type 316 stainless steel. Adding 5 wt % Al to the lithium reduced the weight loss of this steel by a factor of 5 relative to a pure lithium-thermal-convection loop.

  4. Machinability of a Stainless Steel by Electrochemical Discharge Microdrilling

    NASA Astrophysics Data System (ADS)

    Coteaţǎ, Margareta; Schulze, Hans-Peter; Pop, Nicolae; Beşliu, Irina; Slǎtineanu, Laurenţiu

    2011-05-01

    Due to the chemical elements included in their structure for ensuring an increased resistance to the environment action, the stainless steels are characterized by a low machinability when classical machining methods are applied. For this reason, sometimes non-traditional machining methods are applied, one of these being the electrochemical discharge machining. To obtain microholes and to evaluate the machinability by electrochemical discharge microdrilling, test pieces of stainless steel were used for experimental research. The electrolyte was an aqueous solution of sodium silicate with different densities. A complete factorial plan was designed to highlight the influence of some input variables on the sizes of the considered machinability indexes (electrode tool wear, material removal rate, depth of the machined hole). By mathematically processing of experimental data, empirical functions were established both for stainless steel and carbon steel. Graphical representations were used to obtain more suggestive vision concerning the influence exerted by the considered input variables on the size of the machinability indexes.

  5. Machinability of a Stainless Steel by Electrochemical Discharge Microdrilling

    SciTech Connect

    Coteata, Margareta; Pop, Nicolae; Slatineanu, Laurentiu; Schulze, Hans-Peter; Besliu, Irina

    2011-05-04

    Due to the chemical elements included in their structure for ensuring an increased resistance to the environment action, the stainless steels are characterized by a low machinability when classical machining methods are applied. For this reason, sometimes non-traditional machining methods are applied, one of these being the electrochemical discharge machining. To obtain microholes and to evaluate the machinability by electrochemical discharge microdrilling, test pieces of stainless steel were used for experimental research. The electrolyte was an aqueous solution of sodium silicate with different densities. A complete factorial plan was designed to highlight the influence of some input variables on the sizes of the considered machinability indexes (electrode tool wear, material removal rate, depth of the machined hole). By mathematically processing of experimental data, empirical functions were established both for stainless steel and carbon steel. Graphical representations were used to obtain more suggestive vision concerning the influence exerted by the considered input variables on the size of the machinability indexes.

  6. Characterization of Palladium and Palladium-Silver Alloy Layers on Stainless Steel Support

    NASA Astrophysics Data System (ADS)

    Katoh, Masahiro; Sondoh, Akira; Horikawa, Toshihide; Tomida, Tahei

    Pd and Pd/Ag layers were prepared by a technique of electroless plating on stainless steel supports. To form Pd/Ag layers, Pd layer was plated on an activated stainless steel (SS) sheet followed by Ag plating. The Pd/Ag-SS sheet composite was annealed at 873 K-973 K for 10 h -12 h in helium. Before annealing, the thickness of Pd layer and Ag layer on Pd/Ag-SS sheet composite was 7.6 μm and 1.9 μm, respectively. The formation of Pd/Ag alloy was observed on the SS sheet after annealing at 873 K for 12 h in helium. The ratios of Ag/(Pd+Ag) were 0.28 on the surface by XRF and 0.29 in the bulk by XPS. This result showed the formation of homogeneous Pd/Ag alloy on the SS sheet at that annealing condition. Helium permeances were measured at a pressure difference of 1 atm and room temperature. The permeances of porous stainless steel (PSS) tubes without and with 78 μm Pd layer were 100 m3/m2h and 0.35 m3/m2h, respectively. This result showed the obtained membrane was an almost dense membrane.

  7. Study of electroless Ni-W-P alloy coating on martensitic stainless steel

    NASA Astrophysics Data System (ADS)

    Nikitasari, Arini; Mabruri, Efendi

    2016-04-01

    Electroless nickel phospor (Ni-P) is widely used in many industries due to their corrosion and wear resistance, coating uniformity, and ability to coat non-conductive surfaces. The unique properties of tungsten such as high hardness, higher melting point, lower coefficient of linear thermal expansion, and high tensile strength have created a lot of interest in developing ternary Ni-W-P alloys. This article presents the study of electroless Ni-W-P alloys coating using acid or alkaline bath on martensitic stainless steel. Nickel sulfate and sodium tungstate were used as nickel and tungsten sources, respectively, and sodium hypophosphite was used as a reducing agent. Acid or alkaline bath refer to bath pH condition was adjusted by adding sulfuric acid. Martensitic stainless steel was immersed in Ni-W-P bath for 15, 30, and 60 minutes. The substrate of martensitic stainless steel was subjected to pre-treatment (polishing and cleaning) and activation prior to electroless plating. The plating characteristics were investigated for concentration ratio of nickel and hypophosphite (1:3), sodium tungstate concentration 0,1 M, immersion time (15 min, 30 min, 60 min), and bath condition (acid, alkaline). The electroless Ni-W-P plating was heat treated at 400°C for 1 hour. Deposits were characterized using scanning electron microscope (SEM) and corrosion measurement system (CMS).

  8. Antibacterial effect of silver nanofilm modified stainless steel surface

    NASA Astrophysics Data System (ADS)

    Fang, F.; Kennedy, J.; Dhillon, M.; Flint, S.

    2015-03-01

    Bacteria can attach to stainless steel surfaces, resulting in the colonization of the surface known as biofilms. The release of bacteria from biofilms can cause contamination of food such as dairy products in manufacturing plants. This study aimed to modify stainless steel surfaces with silver nanofilms and to examine the antibacterial effectiveness of the modified surface. Ion implantation was applied to produce silver nanofilms on stainless steel surfaces. 35 keV Ag ions were implanted with various fluences of 1 × 1015 to 1 × 1017 ions•cm-2 at room temperature. Representative atomic force microscopy characterizations of the modified stainless steel are presented. Rutherford backscattering spectrometry spectra revealed the implanted atoms were located in the near-surface region. Both unmodified and modified stainless steel coupons were then exposed to two types of bacteria, Pseudomonas fluorescens and Streptococcus thermophilus, to determine the effect of the surface modification on bacterial attachment and biofilm development. The silver modified coupon surface fluoresced red over most of the surface area implying that most bacteria on coupon surface were dead. This study indicates that the silver nanofilm fabricated by the ion implantation method is a promising way of reducing the attachment of bacteria and delay biofilm formation.

  9. Work of adhesion of dairy products on stainless steel surface

    PubMed Central

    Bernardes, Patrícia Campos; Araújo, Emiliane Andrade; dos Santos Pires, Ana Clarissa; Queiroz Fialho Júnior, José Felício; Lelis, Carini Aparecida; de Andrade, Nélio José

    2012-01-01

    The adhesion of the solids presents in food can difficult the process of surface cleaning and promotes the bacterial adhesion process and can trigger health problems. In our study, we used UHT whole milk, chocolate based milk and infant formula to evaluate the adhesion of Enterobacter sakazakii on stainless steel coupons, and we determine the work of adhesion by measuring the contact angle as well as measured the interfacial tension of the samples. In addition we evaluated the hydrophobicity of stainless steel after pre-conditioning with milk samples mentioned. E. sakazakii was able to adhere to stainless steel in large numbers in the presence of dairy products. The chocolate based milk obtained the lower contact angle with stainless steel surface, higher interfacial tension and consequently higher adhesion work. It was verified a tendency of decreasing the interfacial tension as a function of the increasing of protein content. The preconditioning of the stainless steel coupons with milk samples changed the hydrophobic characteristics of the surfaces and became them hydrophilic. Therefore, variations in the composition of the milk products affect parameters important that can influence the procedure of hygiene in surface used in food industry. PMID:24031951

  10. A stainless steel bracket for orthodontic application.

    PubMed

    Oh, Keun-Taek; Choo, Sung-Uk; Kim, Kwang-Mahn; Kim, Kyoung-Nam

    2005-06-01

    Aesthetics has become an essential element when choosing orthodontic fixed appliances. Most metallic brackets used in orthodontic therapy are made from stainless steel (SS) with the appropriate physical properties and good corrosion resistance, and are available as types 304, 316 and 17-4 PH SS. However, localized corrosion of these materials can frequently occur in the oral environment. This study was undertaken to evaluate the accuracy of sizing, microstructure, hardness, corrosion resistance, frictional resistance and cytotoxicity of commercially available Mini-diamond (S17400), Archist (S30403) and experimentally manufactured SR-50A (S32050) brackets. The size accuracy of Mini-diamond was the highest at all locations except for the external horizontal width of the tie wing (P < 0.05). Micrographs of the Mini-diamond and Archist showed precipitates in the grains and around their boundaries. SR-50A showed the only austenitic phase and the highest polarization resistance of the tested samples. SR-50A also had the highest corrosion resistance [SR-50A, Mini-diamond and Archist were 0.9 x 10(-3), 3.7 x 10(-3), and 7.4 x 10(-3) mm per year (mpy), respectively], in the artificial saliva. The frictional force of SR-50A decreased over time, but that of Mini-diamond and Archist increased. Therefore, SR-50A is believed to have better frictional properties to orthodontic wire than Mini-diamond and Archist. Cytotoxic results showed that the response index of SR-50A was 0/1 (mild), Mini-diamond 1/1 (mild+), and Archist 1/2 (mild+). SR-50A showed greater biocompatibility than either Mini-diamond or Archist. It is concluded that the SR-50A bracket has good frictional property, corrosion resistance and biocompatibility with a lower probability of allergic reaction, compared with conventionally used SS brackets. PMID:15947222

  11. Tensile properties of the modified 13Cr martensitic stainless steels

    NASA Astrophysics Data System (ADS)

    Mabruri, Efendi; Anwar, Moch. Syaiful; Prifiharni, Siska; Romijarso, Toni B.; Adjiantoro, Bintang

    2016-04-01

    This paper reports the influence of Mo and Ni on the tensile properties of the modified 13Cr martensitic stainless steels in tempered condition. Four steels with different content of Mo and Ni were prepared by induction melting followed by hot forging, quenching and tempering. The experimental results showed that the addition of about 1% and 3% Mo has a beneficial effect to increase both the tensile strength and the elongation of the steels. On the contrary, the addition of about 3% Ni into the martensitic stainless steel results in decreasing of both the tensile strength and the elongation. Among the alloys investigated the 13Cr3Mo type steel exhibited largest tensile strength of 1348 MPa and largest elongation of 12%. The observation on the tensile fractured surfaces by using scanning electron microscope supported these findings.

  12. Borated stainless steel application in spent-fuel storage racks

    SciTech Connect

    Smith, R.J.; Loomis, G.W.; Deltete, C.P.

    1992-06-01

    EPRI is continuing to investigate the application of borated stainless steel products within the commercial nuclear power industry through participation in code development and material testing. This effort provides documentation of the material properties of interest in design applications utilizing the borated stainless steel products as structural elements as well as serving as neutron absorbers. The properties of most concern in the design of spent fuel storage racks, shipping casks, and other containment type applications are the materials' ductility, tensile strength, corrosion resistance and resistance to degradation due to radiation and temperature. The data presented in this report indicate that practical designs can be achieved utilizing borated stainless steels and that the materials can be cost effectively applied.

  13. Highly robust stainless steel tips as microelectrospray emitters.

    PubMed

    Ishihama, Yasushi; Katayama, Hiroyuki; Asakawa, Naoki; Oda, Yoshiya

    2002-01-01

    Tapered stainless steel spray tips for sheathless microelectrospray ionization (microESI) have been developed. The fabrication procedure for the tapered stainless steel tips was optimized using an electropolishing technique followed by removal of the burr. Using the tip as the microESI emitter, a stable ESI spray was obtained at a flow rate of 20 nL/min. The sensitivity of the microESI system was almost two orders greater than that of the conventional ion spray system. The tip was highly stable, and was successfully used for over 1000 h. Moreover, these stainless steel tips were suitable for use with sheathless capillary electrophoresis/mass spectrometry (CE/MS) and capillary liquid chromatography/mass spectrometry (LC/MS) for routine analysis in proteomic and pharmaceutical applications. PMID:11968120

  14. Microstructure and texture of Nb + Ti stabilized ferritic stainless steel

    SciTech Connect

    Yan Haitao Bi Hongyun; Li Xin; Xu Zhou

    2008-12-15

    The microstructure, texture and grain boundary character distribution of Nb + Ti stabilized ferritic stainless steel were analyzed using scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The addition of alloying elements such as Ti and Nb to ferritic stainless steel causes the formation of TiN, NbC and Fe{sub 2}Nb. The textures of cold rolled samples were dominated by the {alpha}-fiber, while the textures of annealed samples exhibit a very strong {gamma}-fiber. The changes in texture are closely related to the grain boundary characteristics.

  15. Transmission electron microscopy of undermined passive films on stainless steel

    SciTech Connect

    Isaacs, H.S.; Zhu, Y.; Sabatini, R.L.; Ryan, M.P.

    1999-06-01

    A study has been made of the passive film remaining over pits on stainless steel using a high resolution transmission electron microscope. Type 305 stainless steel was passivated in a borate buffer solution and pitted in ferric chloride. Passive films formed at 0.2 V relative to a saturated calomel electrode were found to be amorphous. Films formed at higher potentials showed only broad diffraction rings. The passive film was found to cover a remnant lacy structure formed over pits passivated at 0.8 V. The metallic strands of the lace were roughly hemitubular in shape with the curved surface facing the center of the pit.

  16. Corrosion evaluation of stainless steel root weld shielding

    SciTech Connect

    Gorog, M.; Sawyer, L.A.

    1999-07-01

    The effect of five shielding methods for gas tungsten arc root pass welds, on the corrosion resistance of stainless steel was evaluated in two laboratory solutions. The first experiment was performed in 6% ferric chloride solution, a test designed to corrode stainless steel. The second experiment was performed in a simulated paper machine white water solution that contained hydrogen peroxide. Argon shielding produced excellent results by maintaining corrosion resistance in both solutions. Nitrogen purging and flux coated TIG rod techniques produced variable results. Paste fluxes and welding without shielding are not recommended for root protection. They performed very poorly with the welds corroding in both tests.

  17. Comparison of carbon fiber and stainless steel root canal posts.

    PubMed

    Purton, D G; Payne, J A

    1996-02-01

    This in vitro study compared physical properties of root canal posts made of carbon fiber-reinforced epoxy resin with those of stainless steel posts. Three-point bending tests were used to derive the transverse modulus of elasticity of the posts. Resin composite cores on the posts were subjected to tensile forces to test the bonds between the cores and posts. Carbon fiber posts appeared to have adequate rigidity for their designed purpose. The bond strength of the resin composite cores to the carbon fiber posts was significantly less than that to the stainless steel posts. PMID:9063218

  18. Corrosion induced by cathodic hydrogen in 2205 duplex stainless steel

    NASA Astrophysics Data System (ADS)

    Michalska, J.

    2011-05-01

    In this work new results about the influence of cathodic hydrogen on passivity and corrosion resistance of 2205 duplex stainless steel are described. The results were discussed by taking into account hydrogen charged samples and without hydrogen. The corrosion resistance to pitting was qualified with the polarization curves. The conclusion is that, hydrogen deteriorated the passive film stability and corrosion resistance to pitting of 2205 duplex stainless steel. The presence of hydrogen in passive films increases corrosion current density and decreases the potential of the film breakdown. It was also found that degree of susceptibility to hydrogen action was dependent on the hydrogen charging conditions.

  19. Ozone decay on stainless steel and sugarcane bagasse surfaces

    NASA Astrophysics Data System (ADS)

    Souza-Corrêa, Jorge A.; Oliveira, Carlos; Amorim, Jayr

    2013-07-01

    Ozone was generated using dielectric barrier discharges at atmospheric pressure to treat sugarcane bagasse for bioethanol production. It was shown that interaction of ozone molecules with the pretreatment reactor wall (stainless steel) needs to be considered during bagasse oxidation in order to evaluate the pretreatment efficiency. The decomposition coefficients for ozone on both materials were determined to be (3.3 ± 0.2) × 10-8 for stainless steel and (2.0 ± 0.3) × 10-7 for bagasse. The results have indicated that ozone decomposition has occurred more efficiently on the biomass material.

  20. Characterizing pre-polished Type 304L stainless steel

    SciTech Connect

    Hsu, R.H.; Summer, M.E.; Rankin, W.N.

    1994-10-01

    Prepolished Type 304L stainless steel surfaces are being specified for replacement of some equipment in the 221-H Canyon Building at the Savannah River Site. A prepolished stainless steel surface picks up less contamination than a hot-rolled and pickled surface and is easier to decontaminate; therefore, less waste is generated. Surface-characterization techniques and specification for a prepolished surface were developed to ensure that prepolished items being obtained were properly electropolished. The use of this technology has resulted in obtaining prepolished items with an improved surface finish.

  1. Advanced Cast Austenitic Stainless Steels for High Temperature Components

    SciTech Connect

    Maziasz, P.J.; Shingledecker, J.P.; Evans, N.D.; Pollard, M.J.

    2008-10-09

    In July of 2002, a Cooperative Research and Development Agreement (CRADA) was undertaken between Oak Ridge National Laboratory (ORNL) and Caterpillar, Inc. (Caterpillar Technical Center) to develop and commercialize new cast stainless steels invented and initially tested on a prior CRADA. This CRADA is a direct follow-on project to CRADA ORNL-99-0533 for diesel engine exhaust component and gas turbine engine structural component applications. The goal of this new CRADA was to develop and commercialize the newly discovered cast stainless steels (primarily CF8C-Plus) with improved performance and reliability, as lower-cost upgrade alternatives to more costly cast Ni-based superalloys.

  2. Susceptibility of stainless steel weldments to microbiologically influenced corrosion

    SciTech Connect

    Borenstein, S.W.

    1993-12-31

    Microbiologically influenced corrosion (MIC) is the term used for the phenomenon where corrosion is initiated or accelerated by microorganisms. Biofilms of bacteria form on metal surfaces when exposed to natural waters. The activity of these biofilms and how they attach themselves to metal surfaces directly influence corrosion mechanisms. This paper describes the mechanisms for MIC and the factors which influence the susceptibility of austenitic stainless steel weldments to MIC. The metallurgical, microbiological and electrochemical factors that influence MIC are discussed. Case histories of MIC-related failures and field test results of austenitic stainless steel weldments in various welded conditions are presented.

  3. 49 CFR 178.47 - Specification 4DS welded stainless steel cylinders for aircraft use.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Specification 4DS welded stainless steel cylinders...) SPECIFICATIONS FOR PACKAGINGS Specifications for Cylinders § 178.47 Specification 4DS welded stainless steel... stainless steel sphere (two seamless hemispheres) or circumferentially welded cylinder both with a...

  4. 49 CFR 178.47 - Specification 4DS welded stainless steel cylinders for aircraft use.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Specification 4DS welded stainless steel cylinders...) SPECIFICATIONS FOR PACKAGINGS Specifications for Cylinders § 178.47 Specification 4DS welded stainless steel... stainless steel sphere (two seamless hemispheres) or circumferentially welded cylinder both with a...

  5. 77 FR 60478 - Control of Ferrite Content in Stainless Steel Weld Metal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... COMMISSION Control of Ferrite Content in Stainless Steel Weld Metal AGENCY: Nuclear Regulatory Commission... Ferrite Content in Stainless Steel Weld Metal.'' This guide describes a method that the NRC staff considers acceptable for controlling ferrite content in stainless steel weld metal. Revision 4 updates...

  6. 76 FR 31585 - Forged Stainless Steel Flanges From India: Notice of Rescission of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ... International Trade Administration Forged Stainless Steel Flanges From India: Notice of Rescission of... stainless steel flanges from India. The period of review is February 1, 2010, through January 22, 2011... stainless steel flanges from India. See Antidumping or Countervailing Duty Order, Finding, or...

  7. 76 FR 1599 - Stainless Steel Bar From Brazil: Final Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-11

    ... Less Than Fair Value: Stainless Steel Bar From Brazil, 59 FR 66914 (December 28, 1994). These deposit... International Trade Administration Stainless Steel Bar From Brazil: Final Results of Antidumping Duty... results of its administrative review of the antidumping duty order on stainless steel bar from Brazil....

  8. 77 FR 60673 - Drawn Stainless Steel Sinks From the People's Republic of China: Antidumping Duty Investigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-04

    ... International Trade Administration Drawn Stainless Steel Sinks From the People's Republic of China: Antidumping...'') preliminarily determines that drawn stainless steel sinks (``drawn sinks'') from the People's Republic of China... unfinished, regardless of type of finish, gauge, or grade of stainless steel. Mounting clips,...

  9. 75 FR 67689 - Stainless Steel Bar From Brazil: Preliminary Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-03

    ... Brazil. See Antidumping Duty Orders: Stainless Steel Bar from Brazil, India and Japan, 60 FR 9661... Less Than Fair Value: Stainless Steel Bar From Brazil, 59 FR 66914 (December 28, 1994). These deposit... International Trade Administration Stainless Steel Bar From Brazil: Preliminary Results of Antidumping...

  10. 77 FR 13270 - Stainless Steel Bar From India: Preliminary Results and Partial Rescission of the Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-06

    ... Duty Orders: Stainless Steel Bar from Brazil, India and Japan, 60 FR 9661 (February 21, 1995) (the... Less Than Fair Value: Stainless Steel Bar from India, 59 FR 66915 (December 28, 1994). These deposit... International Trade Administration Stainless Steel Bar From India: Preliminary Results and Partial Rescission...

  11. 75 FR 12514 - Stainless Steel Bar From Brazil: Preliminary Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ... Brazil. See Antidumping Duty Orders: Stainless Steel Bar from Brazil, India and Japan, 60 FR 9661... Review, 73 FR 75398, 75399 (December 11, 2008) (SSPC from Belgium), and Stainless Steel Sheet and Strip... International Trade Administration Stainless Steel Bar From Brazil: Preliminary Results of Antidumping...

  12. Accelerated corrosion of stainless steel in thiocyanate-containing solutions

    SciTech Connect

    Pistorius, P Chris; Li, Wen

    2012-09-19

    It is known that reduced sulfur compounds (such as thiocyanate and thiosulfate) can accelerate active corrosion of austenitic stainless steel in acid solutions, but before we started this project the mechanism of acceleration was largely unclear. This work combined electrochemical measurements and analysis using scanning electron microscopy (SEM) and X-ray photo-electron spectroscopy (XPS), which provided a comprehensive understanding of the catalytic effect of reduced sulfur species on the active corrosion of stainless steel. Both the behavior of the pure elements and the steel were studied and the work focused on the interaction between the pure elements of the steel, which is the least understood area. Upon completion of this work, several aspects are now much clearer. The main results from this work can be summarized as follows: The presence of low concentrations (around 0.1 mM) of thiocyanate or tetrathionate in dilute sulfuric acid greatly accelerates the anodic dissolution of chromium and nickel, but has an even stronger effect on stainless steels (iron-chromium-nickel alloys). Electrochemical measurements and surface analyses are in agreement with the suggestion that accelerated dissolution really results from suppressed passivation. Even well below the passivation potential, the electrochemical signature of passivation is evident in the electrode impedance; the electrode impedance shows clearly that this pre-passivation is suppressed in the presence of thiocyanate. For the stainless steels, remarkable changes in the morphology of the corroded metal surface and in the surface concentration of chromium support the suggestion that pre-passivation of stainless steels is suppressed because dissolution of chromium is accelerated. Surface analysis confirmed that adsorbed sulfur / sulfide forms on the metal surfaces upon exposure to solutions containing thiocyanate or thiosulfate. For pure nickel, and steels containing nickel (and residual copper), bulk sulfide

  13. Electrochemically induced annealing of stainless-steel surfaces.

    PubMed

    Burstein, G T; Hutchings, I M; Sasaki, K

    2000-10-19

    Modification of the surface properties of metals without affecting their bulk properties is of technological interest in demanding applications where surface stability and hardness are important. When austenitic stainless steel is heavily plastically deformed by grinding or rolling, a martensitic phase transformation occurs that causes significant changes in the bulk and surface mechanical properties of the alloy. This martensitic phase can also be generated in stainless-steel surfaces by cathodic charging, as a consequence of lattice strain generated by absorbed hydrogen. Heat treatment of the steel to temperatures of several hundred degrees can result in loss of the martensitic structure, but this alters the bulk properties of the alloy. Here we show that martensitic structures in stainless steel can be removed by appropriate electrochemical treatment in aqueous solutions at much lower temperature than conventional annealing treatments. This electrochemically induced annealing process allows the hardness of cold-worked stainless steels to be maintained, while eliminating the brittle martensitic phase from the surface. Using this approach, we are able to anneal the surface and near-surface regions of specimens that contain rolling-induced martensite throughout their bulk, as well as those containing surface martensite induced by grinding. Although the origin of the electrochemical annealing process still needs further clarification, we expect that this treatment will lead to further development in enhancing the surface properties of metals. PMID:11057662

  14. Bactericidal behavior of Cu-containing stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangyu; Huang, Xiaobo; Ma, Yong; Lin, Naiming; Fan, Ailan; Tang, Bin

    2012-10-01

    Stainless steels are one of the most common materials used in health care environments. However, the lack of antibacterial advantage has limited their use in practical application. In this paper, antibacterial stainless steel surfaces with different Cu contents have been prepared by plasma surface alloying technology (PSAT). The steel surface with Cu content 90 wt.% (Cu-SS) exhibits strong bactericidal activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 3 h. Although the Cu-containing surface with Cu content 2.5 wt.% (CuNi-SS) can also kill all tested bacteria, this process needs 12 h. SEM observation of the bacterial morphology and an agarose gel electrophoresis were performed to study the antibacterial mechanism of Cu-containing stainless steel surfaces against E. coli. The results indicated that Cu ions are released when the Cu-containing surfaces are in contact with bacterial and disrupt the cell membranes, killing the bacteria. The toxicity of Cu-alloyed surfaces does not cause damage to the bacterial DNA. These results provide a scientific explanation for the antimicrobial applications of Cu-containing stainless steel. The surfaces with different antibacterial abilities could be used as hygienic surfaces in healthcare-associated settings according to the diverse requirement of bactericidal activities.

  15. Tensile and creep data on type 316 stainless steel

    SciTech Connect

    Sikka, V. K.; Booker, B. L.P.; Booker, M. K.; McEnerney, J. W.

    1980-01-01

    This report summarizes tensile and creep data on 13 heats of type 316 stainless steel. It includes ten different product forms (three plates, four pipes, and three bars) of the reference heat tested at ORNL. Tensile data are presented in tabular form and analyzed as a function of temperature by the heat centering method. This method yielded a measure of variations within a single heat as well as among different heats. The upper and lower scatter bands developed by this method were wider at the lower temperatures than at the high temperatures (for strength properties), a trend reflected by the experimental data. The creep data on both unaged and aged specimens are presented in tabular form along with creep curves for each test. The rupture time data are compared with the ASME Code Case minimum curve at each test temperature in the range from 538 to 704{sup 0}C. The experimental rupture time data are also compared with the values predicted by using the rupture model based on elevated-temperature ultimate tensile strength. A creep ductility trend curve was developed on the basis of the reference heat data and those published in the literature on nitrogen effects. To characterize the data fully, information was also supplied on vendor, product form, fabrication method, material condition (mill-annealed vs laboratory annealed and aged), grain size, and chemical composition for various heats. Test procedures used for tensile and creep results are also discussed.

  16. No corrosion of 304 stainless steel implant after 40 years of service.

    PubMed

    Blackwood, D J; Pereira, B P

    2004-07-01

    When exposed to 0.9% NaCl type 304 stainless steel undergoes severe pitting corrosion within a matter of days. However, a Sherman plate fabricated from type 304 stainless steel remained inside a patient's arm for almost 40 years without any visible indications of corrosion. Given the previous understanding of the pathological environments this was considered quite remarkable. It is proposed that the low dissolved oxygen levels found in human-body fluids makes the long-term in vivo environment much more benign than would be anticipated from in vitro experiments. Furthermore, it is proposed that previous cases of localized pitting corrosion on stainless steel implants most likely arose due to the development of short-term aggressive conditions due to pathological changes in the surrounding tissue as a result of the trauma of the implant procedure. In the present case the Sherman plate was sufficiently small that the surrounding tissue was not aggravated sufficiently to lead to the development of such an environment aggressive. The conclusion that surgical implants are at most risk during the first few weeks of service implies that short-term corrosion protection methods, such as coatings, may be more effective than previously thought. PMID:15387410

  17. Using stainless steels as long-lasting rebar material

    SciTech Connect

    Smith, F.N.; Tullmin, M.

    1999-05-01

    Corrosion of carbon steel (CS) reinforcing bars (rebars) is a major cause of damage and failure in reinforced concrete structures. A more corrosion resistant rebar material is needed to replace CS in the critical parts of these structures. Stainless steels (SS) have shown considerable promise in terms of the corrosion resistance and mechanical properties required to fulfill this role. Although SS rebars are more expensive, their use can be justified on a life-cycle cost basis.

  18. 37. REDUCTION PLANT DRYER Stainless steel screen cylinder, encased ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. REDUCTION PLANT - DRYER Stainless steel screen cylinder, encased within an outer steel shell (top half missing). As fish were tumbled by the rotating screen, they were cooked and dried by live steam piped into the dryer through overhead pipes. The dryer is mounted on a slight angle, aiding the process by moving the drying fish towards the exhaust end of the dryer. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  19. Mechanical properties of low-nickel stainless steel

    NASA Technical Reports Server (NTRS)

    Montano, J. W.

    1978-01-01

    Demand for improved corrosion-resistant steels, coupled with increased emphasis on conserving strategic metals, has led to development of family of stainless steels in which manganese and nitrogen are substituted for portion of usual nickel content. Advantages are approximately-doubled yield strength in annealed condition, better resistance to stress-corrosion cracking, retention of low magnetic permeability even after severe cold working, excellent strength and ductility at cryogenic temperatures, superior resistance to wear and galling, and excellent high-temperature properties.

  20. Final Report, Volume 1, Metallurgical Evaluation of Cast Duplex Stainless Steels and their Weldments

    SciTech Connect

    Wen, Songqing; Lundin, Carl, W.; Batten, Greg, W.

    2005-09-30

    Duplex stainless steels (DSS) are being specified for chloride containing environments due to their enhanced pitting and stress corrosion cracking resistance. They exhibit improved corrosion performance over the austenitic stainless steels. Duplex stainless steels also offer improved strength properties and are available in various wrought and cast forms. Selected grades of duplex stainless steel castings and their welds, in comparison with their wrought counterparts, were evaluated, regarding corrosion performance and mechanical properties and weldability. Multiple heats of cast duplex stainless steel were evaluated in the as-cast, solution annealed (SA) static cast and SA centrifugal cast conditions, while their wrought counterparts were characterized in the SA condition and in the form of as-rolled plate. Welding, including extensive assessment of autogenous welds and a preliminary study of composite welds (shielded metal arc weld (SMAW)), was performed. The evaluations included critical pitting temperature (CPT) testing, intergranular corrosion (IGC) testing, ASTM A923 (Methods A, B and C), Charpy impact testing, weldability testing (ASTM A494), ferrite measurement and microstructural evaluations. In the study, the corrosion performances of DSS castings were characterized and assessed, including the wrought counterparts for comparison. The evaluation filled the pore of lack of data for cast duplex stainless steels compared to wrought materials. A database of the pitting corrosion and IGC behavior of cast and wrought materials was generated for a greater depth of understanding for the behavior of cast duplex stainless steel. In addition, improved evaluation methods for DSS castings were developed according to ASTM A923, A262, G48 and A494. The study revealed that when properly heat treated according to the specification, (1) DSS castings have equal or better pitting and intergranular corrosion resistance than their wrought counterparts; (2) Welding reduces the

  1. Final Report, Volume 1, Metallurgical Evaluation of Cast Duplex Stainless Steels and their Weldments

    SciTech Connect

    Wen, Songqing; Lundin, Carl, W.; Batten, Greg, W.

    2005-09-30

    Duplex stainless steels (DSS) are being specified for chloride containing environments due to their enhanced pitting and stress corrosion cracking resistance. They exhibit improved corrosion performance over the austenitic stainless steels. Duplex stainless steels also offer improved strength properties and are available in various wrought and cast forms. Selected grades of duplex stainless steel castings and their welds, in comparison with their wrought counterparts, were evaluated, regarding corrosion performance and mechanical properties and weldability. Multiple heats of cast duplex stainless steel were evaluated in the as-cast, solution annealed (SA) static cast and SA centrifugal cast conditions, while their wrought counterparts were characterized in the SA condition and in the form of as-rolled plate. Welding, including extensive assessment of autogenous welds and a preliminary study of composite welds (shielded metal arc weld (SMAW)), was performed. The evaluations included critical pitting temperature (CPT) testing, intergranular corrosion (IGC) testing, ASTM A923 (Methods A, B and C), Charpy impact testing, weldability testing (ASTM A494), ferrite measurement and microstructural evaluations. In the study, the corrosion performances of DSS castings were characterized and assessed, including the wrought counterparts for comparison. The evaluation filled the pore of lack of data for cast duplex stainless steels compared to wrought materials. A database of the pitting corrosion and IGC behavior of cast and wrought materials was generated for a greater depth of understanding for the behavior of cast duplex stainless steel. In addition, improved evaluation methods for DSS castings were developed according to ASTM A923, A262, G48 and A494. The study revealed that when properly heat treated according to the specification, (1) DSS castings have equal or better pitting and intergranular corrosion resistance than their wrought counterparts; (2) Welding reduces the

  2. Stainless steels with improved strength for service at 760 C and above

    SciTech Connect

    Swindeman, R.W.

    1998-03-01

    An evaluation was undertaken of modified 25Cr-20Ni stainless steels and a modified 20Cr-25Ni-Nb stainless steel for advanced energy applications at 760 C (1,400 F) and higher. It was found that good fabricability, strength, and ductility could be produced in the modified steels. Stress rupture data to beyond 10,000 h showed that the strengths of the modified steels were more than double that for type 310H stainless steel.

  3. Properties of super stainless steels for orthodontic applications.

    PubMed

    Oh, Keun-Taek; Kim, Young-Sik; Park, Yong-Soo; Kim, Kyoung-Nam

    2004-05-15

    Orthodontic stainless-steel appliances are considered to be corrosion resistant, but localized corrosion can occur in the oral cavity. This study was undertaken to evaluate the properties of super stainless steels in orthodontic applications. Accordingly, the metallurgical properties, mechanical properties, corrosion resistance, amount of the released nickel, cytotoxicity, and characteristics of the passive film were investigated. Corrosion resistances of the specimens were high and in the following order: super austenitic stainless steel (SR-50A) > super ferritic stainless steel (SFSS) = super duplex stainless steel (SR-6DX) > 316L SS > super martensitic stainless steel (SR-3Mo) in artificial saliva, 37 degrees C. At 500 mV (SCE), current densities of SR-50A, SFSS, SR-6DX, 316L SS, and SR-3Mo were 5.96 microA/cm(2), 20.3 microA/cm(2), 31.9 microA/cm(2), 805 microA/cm(2), and 5.36 mA/cm(2), respectively. Open circuit potentials of SR-50A, 316L SS, SR-6DX, SR-3Mo, and SFSS were - 0.2, - 0.22, - 0.24, - 0.43, and - 0.46 V (SCE), respectively. SR-50A, SFSS, and SR-6DX released below 3 ng/ml nickel for 8 weeks, and increased a little with immersion time, and 316L SS released about 3.5 ng/ml nickel, but SR-3Mo released a large amount of nickel, which increased with immersion time. The study demonstrated that SR-50A, SR-6DX, and SFSS have high corrosion resistance and mild or no cytotoxicity, due to the passive film enhanced by synergistic effect of Mo + N or by high addition effect of Cr + W. All super stainless steels showed very low cytotoxicity regardless of their nickel contents, although SR-3Mo was found to be relatively cytotoxic. From these studies, these steels are considered suitable for orthodontic applications. PMID:15116408

  4. Removal of long-lived 222Rn daughters by electropolishing thin layers of stainless steel

    NASA Astrophysics Data System (ADS)

    Schnee, R. W.; Bowles, M. A.; Bunker, R.; McCabe, K.; White, J.; Cushman, P.; Pepin, M.; Guiseppe, V. E.

    2013-08-01

    Long-lived alpha and beta emitters in the 222Rn decay chain on detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay. Removal of tens of microns of material via electropolishing has been shown to be effective at removing radon daughters implanted into material surfaces. Some applications, however, require the removal of uniform and significantly smaller thicknesses. Here, we demonstrate that electropolishing < 1 μm from stainless-steel plates reduces the contamination efficiently, by a factor > 100. Examination of electropolished wires with a scanning electron microscope confirms that the thickness removed is reproducible and reasonably uniform. Together, these tests demonstrate the effectiveness of removal of radon daughters for a proposed low-radiation, multi-wire proportional chamber (the BetaCage), without compromising the screener's energy resolution. More generally, electropolishing thin layers of stainless steel may effectively remove radon daughters without compromising precision-machined parts.

  5. 77 FR 1504 - Stainless Steel Wire Rod From India

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-10

    ... Commission instituted this review on July 1, 2011 (76 FR 38686) and determined on October 4, 2011, that it would conduct an expedited review (76 FR 64105, October 17, 2011). The Commission transmitted its... COMMISSION Stainless Steel Wire Rod From India Determination On the basis of the record \\1\\ developed in...

  6. Gas Leak from Vinyl Taped Stainless Steel Dressing Jars

    SciTech Connect

    Tim Hayes

    1999-03-01

    The leak rates of nitrogen gas from stainless steel dressing jars taped with 2 inch vinyl tape were measured. These results were used to calculate hydrogen leak rates from the same jars. The calculations show that the maximum concentration of hydrogen buildup in this type of container configuration will beat least 3 orders of magnitude below the lower explosion limit for hydrogen in air.

  7. Battery and fuel cell electrodes containing stainless steel charging additive

    DOEpatents

    Zuckerbrod, David; Gibney, Ann

    1984-01-01

    An electrode for use in electrochemical energy cells is made, comprising a hydrophilic layer and a hydrophobic layer, where the hydrophilic layer comprises a hydrophilic composite which includes: (i) carbon particles; (ii) stainless steel particles; (iii) a nonwetting agent; and (iv) a catalyst, where at least one current collector contacts said composite.

  8. Stainless steel 301 and Inconel 718 hydrogen embrittlement

    NASA Technical Reports Server (NTRS)

    Allgeier, R. K.; Forman, R.

    1970-01-01

    Conditions and results of tensile tests of 26 Inconel 718 and four cryoformed stainless steel specimens are presented. Conclusions determine maximum safe hydrogen operating pressure for cryogenic pressure vessels and provide definitive information concerning flaw growth characteristics under the most severe temperature and pressure conditions

  9. Behavior of stainless steels in pressurized water reactor primary circuits

    NASA Astrophysics Data System (ADS)

    Féron, D.; Herms, E.; Tanguy, B.

    2012-08-01

    Stainless steels are widely used in primary circuits of pressurized water reactors (PWRs). Operating experience with the various grades of stainless steels over several decades of years has generally been excellent. Nevertheless, stress corrosion failures have been reported in few cases. Two main factors contributing to SCC susceptibility enhancement are investigated in this study: cold work and irradiation. Irradiation is involved in the stress corrosion cracking and corrosion of in-core reactor components in PWR environment. Irradiated assisted stress corrosion cracking (IASCC) is a complex and multi-physics phenomenon for which a predictive modeling able to describe initiation and/or propagation is not yet achieved. Experimentally, development of initiation smart tests and of in situ instrumentation, also in nuclear reactors, is an important axis in order to gain a better understanding of IASCC kinetics. A strong susceptibility for SCC of heavily cold worked austenitic stainless steels is evidenced in hydrogenated primary water typical of PWRs. It is shown that for a given cold-working procedure, SCC susceptibility of austenitic stainless steels materials increases with increasing cold-work. Results have shown also strong influences of the cold work on the oxide layer composition and of the maximum stress on the time to fracture.

  10. Metal release from stainless steel in biological environments: A review.

    PubMed

    Hedberg, Yolanda S; Odnevall Wallinder, Inger

    2016-03-01

    Due to its beneficial corrosion resistance, stainless steel is widely used in, e.g., biomedical applications, as surfaces in food contact, and for products intended to come into skin contact. Low levels of metals can be released from the stainless steel surface into solution, even for these highly corrosion resistant alloys. This needs to be considered in risk assessment and management. This review aims to compile the different metal release mechanisms that are relevant for stainless steel when used in different biological settings. These mechanisms include corrosion-induced metal release, dissolution of the surface oxide, friction-induced metal release, and their combinations. The influence of important physicochemical surface properties, different organic species and proteins in solution, and of biofilm formation on corrosion-induced metal release is discussed. Chemical and electrochemical dissolution mechanisms of the surface oxides of stainless steel are presented with a focus on protonation, complexation/ligand-induced dissolution, and reductive dissolution by applying a perspective on surface adsorption of complexing or reducing ligands and proteins. The influence of alloy composition, microstructure, route of manufacture, and surface finish on the metal release process is furthermore discussed as well as the chemical speciation of released metals. Typical metal release patterns are summarized. PMID:26514345

  11. 304L stainless steel resistance to cesium chloride

    SciTech Connect

    Graves, C.E.

    1998-08-27

    B and W Hanford Company have two Oak Ridge National Laboratory (ORNL) Type 4 canisters filled with cesium chloride (CsCl) originally produced at WESF (Waste Encapsulation and Storage Facility). These canisters are constructed of 304L stainless steel per drawing ORNL 970-294. Instead of removing the CsCl from the Type 4 canisters and repacking into an Inner Capsule, it is intended (for ALARA, schedule and cost purposes) that the Type 4 canisters be decontaminated (scrubbed) and placed [whole] inside a Type ``W`` overpack. The overpack is constructed from 316L stainless steel. Several tests have been run by Pacific Northwest National Laboratory (PNNL) over the. years documenting the corrosion compatibility of 316L SS with CsCl (Bryan 1989 and Fullam 1972). However, no information for 304L SS compatibility is readily available. This document estimates the corrosion resistance of 304L stainless steel in a WESF CsCl environment as it compares with that of 316L stainless steel.

  12. [The question of nickel release from stainless steel cooking pots].

    PubMed

    Vrochte, H; Schätzke, M; Dringenberg, E; Wölwer-Rieck, U; Büning-Pfaue, H

    1991-09-01

    For three items of foods (rhubarb, spinach, sauerkraut) the possible release of nickel (by means of AAS) was analysed, a release which may be caused by a possible corrosive effect of the concerned (oxalic-, milk-, vinegar-) acids (as well as common salt) within a normal domestic food-preparation. For this analysis stainless steel cooking pots of different manufacturers, various types and in a representative selection and quantity were taken into consideration; the detailed analyses were extended so far that clear statistical evaluations were possible. This method complies regulations for accuracy to determine traces of heavy metal. For all three analysed food-stuffs an identical result was reached that no nickel release from the stainless steel cooking pots into the food was found. Differences of the various stainless steel cooking pots with regard to their surfaces' quality or their origin (manufacturers) were not yielded, either. All detected concentrations of nickel are within the reach of the natural nickel content of the analysed food-stuffs and their amount is even much lower than other food's content of nickel. This leads up to the conclusion that the former view of a possible nickel release of stainless steel cooking pots has to be revised because these assumptions were not confirmed in the presented results of this analysis and therefore have to be regarded as not correct. PMID:1763555

  13. 2. GENERAL VIEW OF STAINLESS STEEL SMOKEHOUSES ON LEVEL 6, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. GENERAL VIEW OF STAINLESS STEEL SMOKEHOUSES ON LEVEL 6, LOOKING EAST; SMOKEHOUSE UNITS WERE BUILT BY DRYING SYSTEMS COMPANY, DIVISION OF MICHIGAN OVEN COMPANY, MORTON GROVE, ILLINOIS - Rath Packing Company, Smokehouse-Hog Chilling Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  14. 6. DETAIL OF STAINLESS STEEL VISCERA CHUTE IN SOUTHEAST CORNER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL OF STAINLESS STEEL VISCERA CHUTE IN SOUTHEAST CORNER OF LEVEL4; ENTRAILS WERE DROPPED INTO CHUTE, THEN PASSED THROUGH THE FLOOR TO THE GUT SHANTY ON LEVEL 3 TO BE SORTED AND CLEANED - Rath Packing Company, Hog Dressing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  15. Lithium wetting of stainless steel for plasma facing components

    NASA Astrophysics Data System (ADS)

    Skinner, C. H.; Capece, A. M.; Roszell, J. P.; Koel, B. E.

    2014-10-01

    Ensuring continuous wetting of a solid container by the liquid metal is a critical issue in the design of liquid metal plasma facing components foreseen for NSTX-U and FNSF. Ultrathin wetting layers may form on metallic surfaces under ultrahigh vacuum (UHV) conditions if material reservoirs are present from which spreading and wetting can start. The combined scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and ion beam etching capabilities of a Scanning Auger Microprobe (SAM) have been used to study the spreading of lithium films on stainless steel substrates. A small (mm-scale) amount of metallic lithium was applied to a stainless steel surface in an argon glove box and transferred to the SAM. Native impurities on the stainless steel and lithium surfaces were removed by Ar+ ion sputtering. Elemental mapping of Li and Li-O showed that surface diffusion of Li had taken place at room temperature, well below the 181°C Li melting temperature. The influence of temperature and surface oxidation on the rate of Li spreading on stainless steel will be reported. Support was provided through DOE Contract Number DE-AC02-09CH11466.

  16. Graphene Nanoplatelets Based Protective and Functionalizing Coating for Stainless Steel.

    PubMed

    Mondal, Jayanta; Kozlova, Jekaterina; Sammelselg, Väino

    2015-09-01

    Stainless steel is the most widely used alloy for many industrial and everyday applications, and protection of this alloy substrate against corrosion is an important industrial issue. Here we report a promising application of graphene oxide and graphene nanoplatelets as effective corrosion inhibitors for AISI type 304 stainless steel alloy. The graphene oxide and graphene coatings on the stainless steel substrates were prepared using spin coating techniques. Homogeneous and complete surface coverage by the graphene oxide and graphene nanoplatelets were observed with a high-resolution scanning electron microscope. The corrosion inhibition ability of these materials was investigated through measurement of open circuit potential and followed by potentiodymamic polarization analysis in aqueous sodium chloride solution before and after a month of immersion. Analyzed result exhibits effective corrosion inhibition for both substrates coated with graphene oxide or graphene nanoplatelets by increasing corrosion potential, pitting potential and decreasing passive current density. The corrosion inhibition ability of the coated substrates has not changed even after the long-term immersion. The result showed both graphene materials can be used as an effective corrosion inhibitor for the stainless steel substrates, which would certainly increase lifetime the substrate. However, long-term protection ability of the graphene coated susbtsrate showed somewhat better inhibition performance than the ones coated with graphene oxide. PMID:26716239

  17. Reactor Material Program Fracture Toughness of Type 304 Stainless Steel

    SciTech Connect

    Awadalla, N.G.

    2001-03-28

    This report describes the experimental procedure for Type 304 Stainless Steel fracture toughness measurements and the application of results. Typical toughness values are given based on the completed test program for the Reactor Materials Program (RMP). Test specimen size effects and limitations of the applicability in the fracture mechanics methodology are outlined as well as a brief discussion on irradiation effects.

  18. 73. View of line of stainless steel coolant storage tanks ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    73. View of line of stainless steel coolant storage tanks for bi-sodium sulfate/water coolant solution at first floor of transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  19. Materials data handbook: Stainless steel alloy A-286

    NASA Technical Reports Server (NTRS)

    Muraca, R. F.; Whittick, J. S.

    1972-01-01

    A summary of the materials property information for stainless steel alloy A-286 is presented. The scope of the information includes physical and mechanical properties at cryogenic, ambient, and elevated temperatures. Information on material procurement, metallurgy of the alloy, corrosion, environmental effects, fabrication, and bonding is developed.

  20. Method of forming dynamic membrane on stainless steel support

    NASA Technical Reports Server (NTRS)

    Gaddis, Joseph L. (Inventor); Brandon, Craig A. (Inventor)

    1988-01-01

    A suitable member formed from sintered, powdered, stainless steel is contacted with a nitrate solution of a soluble alkali metal nitrate and a metal such as zirconium in a pH range and for a time sufficient to effect the formation of a membrane of zirconium oxide preferably including an organic polymeric material such as polyacrylic acid.

  1. Failure Assessment Diagram for Brazed 304 Stainless Steel Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yory

    2011-01-01

    Interaction equations were proposed earlier to predict failure in Albemet 162 brazed joints. Present study demonstrates that the same interaction equations can be used for lower bound estimate of the failure criterion in 304 stainless steel joints brazed with silver-based filler metals as well as for construction of the Failure Assessment Diagrams (FAD).

  2. Alternative to Nitric Acid for Passivation of Stainless Steel Alloys

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie L.; Kolody, Mark; Curran, Jerry

    2013-01-01

    Corrosion is an extensive problem that affects the Department of Defense (DoD) and National Aeronautics and Space Administration (NASA). The deleterious effects of corrosion result in steep costs, asset downtime affecting mission readiness, and safety risks to personnel. Consequently, it is vital to reduce corrosion costs and risks in a sustainable manner. The DoD and NASA have numerous structures and equipment that are fabricated from stainless steel. The standard practice for protection of stainless steel is a process called passivation. Typical passivation procedures call for the use of nitric acid; however, there are a number of environmental, worker safety, and operational issues associated with its use. Citric acid offers a variety of benefits including increased safety for personnel, reduced environmental impact, and reduced operational cost. DoD and NASA agreed to collaborate to validate citric acid as an acceptable passivating agent for stainless steel. This paper details our investigation of prior work developing the citric acid passivation process, development of the test plan, optimization of the process for specific stainless steel alloys, ongoing and planned testing to elucidate the process' resistance to corrosion in comparison to nitric acid, and preliminary results.

  3. Effect of ultrafine grain on tensile behaviour and corrosion resistance of the duplex stainless steel.

    PubMed

    Jinlong, Lv; Tongxiang, Liang; Chen, Wang; Limin, Dong

    2016-05-01

    The ultrafine grained 2205 duplex stainless steel was obtained by cold rolling and annealing. The tensile properties were investigated at room temperature. Comparing with coarse grained stainless steel, ultrafine grained sample showed higher strength and plasticity. In addition, grain size changed deformation orientation. The strain induced α'-martensite was observed in coarse grained 2205 duplex stainless steel with large strain. However, the grain refinement inhibited the transformation of α'-martensite;nevertheless, more deformation twins improved the strength and plasticity of ultrafine grained 2205 duplex stainless steel. In addition, the grain refinement improved corrosion resistance of the 2205 duplex stainless steel in sodium chloride solution. PMID:26952459

  4. Application of electron backscattered diffraction to cleavage fracture in duplex stainless steel

    SciTech Connect

    Kim, S.; Marrow, T.J.

    1999-05-21

    The mechanical properties and corrosion resistance of duplex stainless steel (DSS) are generally superior to conventional austenite or ferrite grades. DSSs can have yield strengths twice the austenite grades, while retaining good ductility and toughness properties. Commercial wrought duplex stainless steels, either plates or rod, are processed by hot rolling followed by a solution annealing treatment to optimize the austenite-ferrite ratio and dissolve any pre-existing secondary phases. Processing may lead to a significant anisotropy in mechanical properties. For example, the tensile properties in cold-rolled sheet of duplex stainless steel (22Cr5Ni) reveals anisotropy of strength, i.e., the transverse direction tensile strength is 7.3% higher than tensile strength in the rolling direction (RD). It was also shown in a study of the effect of crack orientation on the impact properties of the same steel, that when the crack was oriented parallel to the direction of elongation of the austenite phase, the crack could grow along the more brittle ferrite phase for a longer distance before encountering the more ductile austenite. This decreased impact toughness. These are examples of microstructure texture. Crystallographic texture may also have an effect on properties that are related to specific crystallographic planes; such as brittle cleavage and stress corrosion cracking. This paper describes the application of electron backscattered diffraction (EBSD) to study cleavage fracture and crystal texture in age-hardened DSS.

  5. Practical method of diffusion-welding steel plate in air

    NASA Technical Reports Server (NTRS)

    Holko, K. H.; Moore, T. J.

    1971-01-01

    Method is ideal for critical service requirements where parent metal properties are equaled in notch toughness, stress rupture and other characteristics. Welding technique variations may be used on a variety of materials, such as carbon steels, alloy steels, stainless steels, ceramics, and reactive and refractory materials.

  6. Standard specification for pressure vessel plates, alloy steel, quenched-and-tempered, chromium-molybdenum, and chromium-molybdenum-vanadium. ASTM standard

    SciTech Connect

    1995-08-01

    This specification is under the jurisdiction of ASTM Committee A-1 on Steel, Stainless Steel, and Related Alloys and is the responsibility of Subcommittee A01.11 on Steel Plates for Boiler and Pressure Vessels. Current edition approved Jun. 15, 1995. Published August 1995. Originally published as A 542-65. Last previous edition A 542/A 542M-93.

  7. Fracture properties of a neutron-irradiated stainless steel submerged arc weld cladding overlay

    SciTech Connect

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-01-01

    The ability of stainless steel cladding to increase the resistance of an operating nuclear reactor pressure vessel to extension of surface flaws depends greatly on the properties of the irradiated cladding. Therefore, weld overlay cladding irradiated at temperatures and fluences relevant to power reactor operation was examined. The cladding was applied to a pressure vessel steel plate by the submerged arc, single-wire, oscillating-electrode method. Three layers of cladding provided a thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. The type 309 was diluted considerably by excessive melting of the base plate. Specimens were taken from near the base plate-cladding interface and also from the upper layers. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to a fluence of 2 x 10/sup 23/ neutrons/m/sup 2/ (>1 MeV). 10 refs., 16 figs., 4 tabs.

  8. Study of austenitic stainless steel welded with low alloy steel filler metal. [tensile and impact strength tests

    NASA Technical Reports Server (NTRS)

    Burns, F. A.; Dyke, R. A., Jr.

    1979-01-01

    The tensile and impact strength properties of 316L stainless steel plate welded with low alloy steel filler metal were determined. Tests were conducted at room temperature and -100 F on standard test specimens machined from as-welded panels of various chemical compositions. No significant differences were found as the result of variations in percentage chemical composition on the impact and tensile test results. The weldments containing lower chromium and nickel as the result of dilution of parent metal from the use of the low alloy steel filler metal corroded more severely in a marine environment. The use of a protective finish, i.e., a nitrile-based paint containing aluminum powder, prevented the corrosive attack.

  9. Low Temperature Surface Carburization of Stainless Steels

    SciTech Connect

    Collins, Sunniva R; Heuer, Arthur H; Sikka, Vinod K

    2007-12-07

    Low-temperature colossal supersaturation (LTCSS) is a novel surface hardening method for carburization of austenitic stainless steels (SS) without the precipitation of carbides. The formation of carbides is kinetically suppressed, enabling extremely high or colossal carbon supersaturation. As a result, surface carbon concentrations in excess of 12 at. % are routinely achieved. This treatment increases the surface hardness by a factor of four to five, improving resistance to wear, corrosion, and fatigue, with significant retained ductility. LTCSS is a diffusional surface hardening process that provides a uniform and conformal hardened gradient surface with no risk of delamination or peeling. The treatment retains the austenitic phase and is completely non-magnetic. In addition, because parts are treated at low temperature, they do not distort or change dimensions. During this treatment, carbon diffusion proceeds into the metal at temperatures that constrain substitutional diffusion or mobility between the metal alloy elements. Though immobilized and unable to assemble to form carbides, chromium and similar alloying elements nonetheless draw enormous amounts of carbon into their interstitial spaces. The carbon in the interstitial spaces of the alloy crystals makes the surface harder than ever achieved before by more conventional heat treating or diffusion process. The carbon solid solution manifests a Vickers hardness often exceeding 1000 HV (equivalent to 70 HRC). This project objective was to extend the LTCSS treatment to other austenitic alloys, and to quantify improvements in fatigue, corrosion, and wear resistance. Highlights from the research include the following: • Extension of the applicability of the LTCSS process to a broad range of austenitic and duplex grades of steels • Demonstration of LTCSS ability for a variety of different component shapes and sizes • Detailed microstructural characterization of LTCSS-treated samples of 316L and other alloys

  10. Cavitation Erosion of Sensitized UNS S31803 Duplex Stainless Steels

    NASA Astrophysics Data System (ADS)

    Mitelea, Ion; Micu, Lavinia Mădălina; Bordeaşu, Ilare; Crăciunescu, Corneliu Marius

    2016-05-01

    During processing or use, duplex steels can be subjected to heating at high temperatures that can affect their behavior. This work aims to correlate the influence of the sensitization treatment on the ultrasonic cavitation erosion behavior of a UNS S31803 (X2CrNiMoN22-5-3) duplex stainless steel. Duplex stainless steels, formed as a result of rapid cooling after solution annealing, are sensitized at temperatures of 475 and 850 °C, respectively, leading to hardening and embrittlement due to the spinodal decomposition of the ferrite and the precipitation of secondary phases. The ultrasonic cavitation erosion experiments showed that the sensitization at 850 °C reduced the mean depth of erosion by about 11% and the mean depth of erosion rate by 28%. By contrast, the sensitization at 475 °C deteriorates the cavitation erosion resistance, increasing the erosion parameters by up to 22%, compared to the solution annealed state.

  11. Cavitation Erosion of Sensitized UNS S31803 Duplex Stainless Steels

    NASA Astrophysics Data System (ADS)

    Mitelea, Ion; Micu, Lavinia Mădălina; Bordeaşu, Ilare; Crăciunescu, Corneliu Marius

    2016-04-01

    During processing or use, duplex steels can be subjected to heating at high temperatures that can affect their behavior. This work aims to correlate the influence of the sensitization treatment on the ultrasonic cavitation erosion behavior of a UNS S31803 (X2CrNiMoN22-5-3) duplex stainless steel. Duplex stainless steels, formed as a result of rapid cooling after solution annealing, are sensitized at temperatures of 475 and 850 °C, respectively, leading to hardening and embrittlement due to the spinodal decomposition of the ferrite and the precipitation of secondary phases. The ultrasonic cavitation erosion experiments showed that the sensitization at 850 °C reduced the mean depth of erosion by about 11% and the mean depth of erosion rate by 28%. By contrast, the sensitization at 475 °C deteriorates the cavitation erosion resistance, increasing the erosion parameters by up to 22%, compared to the solution annealed state.

  12. Evaluation of the wear properties of high interstitial stainless steels

    SciTech Connect

    Tylczak, J.H.; Rawers, J.C.; Alman, D.E.

    2007-04-01

    Adding carbon to high nitrogen steels increases interstitial concentrations over what can be obtained with nitrogen addition alone. This can results in an increase in hardness, strength, and wear resistance. The alloys produced for this study were all based on commercially available high-nitrogen Fe-18Cr-18Mn stainless steel. This study is the first significant wear study of these new high interstitial nitrogen-carbon stainless steel alloys. Wear tests included: scratch, pin-on-disk abrasion, dry sand/rubber wheel abrasion, impeller impact, and jet erosion. Increasing interstitial concentration increased strength and hardness and improved wear resistance under all test conditions. The results are discussed in terms of overall interstitial alloy concentration.

  13. Achievement of a superpolish on bare stainless steel

    SciTech Connect

    Howells, M.R.; Casstevens, J.

    1997-08-01

    We report the achievement of a superpolished surface, suitable for x-ray reflection, on bare stainless steel. The rms roughness obtained on various samples varied from 2.2 to 4.2 {angstrom}, as measured by an optical profiler with a bandwidth 0.29-100 mm{sup -1}. The type 17-4 PH precipitation-hardening stainless steel used to make the mirrors is also capable of ultrastability and has good manufactureability. This combination of properties makes it an excellent candidate material for mirror substrates. We describe the successful utilization of this type of steel in making elliptical-cylinder mirrors for a soft-x-ray microprobe system at the Advanced Light Source, and discuss possible for its unusual stability and polishability.

  14. 2012 ACCOMPLISHMENTS - TRITIUM AGING STUDIES ON STAINLESS STEELS

    SciTech Connect

    Morgan, M.

    2013-01-31

    This report summarizes the research and development accomplishments during FY12 for the tritium effects on materials program. The tritium effects on materials program is designed to measure the long-term effects of tritium and its radioactive decay product, helium-3, on the structural properties of forged stainless steels which are used as the materials of construction for tritium reservoirs. The FY12 R&D accomplishments include: (1) Fabricated and Thermally-Charged 150 Forged Stainless Steel Samples with Tritium for Future Aging Studies; (2) Developed an Experimental Plan for Measuring Cracking Thresholds of Tritium-Charged-and-Aged Steels in High Pressure Hydrogen Gas; (3) Calculated Sample Tritium Contents For Laboratory Inventory Requirements and Environmental Release Estimates; (4) Published report on “Cracking Thresholds and Fracture Toughness Properties of Tritium-Charged-and-Aged Stainless Steels”; and, (5) Published report on “The Effects of Hydrogen, Tritium, and Heat Treatment on the Deformation and Fracture Toughness Properties of Stainless Steels”. These accomplishments are highlighted here and references given to additional reports for more detailed information.

  15. The effect of dose rate on the response of austenitic stainless steels to neutron radiaiton

    SciTech Connect

    Allen, T. R.; Cole, J I.; Trybus, Carole L.; Porter, D. L.; Tsai, Hanchung; Garner, Francis A.; Kenik, E A.; Yoshitake, T.; Ohta, Joji

    2006-01-01

    Depending on reactor design and component location, austenitic stainless steels may experience significantly different irradiation dose rates in the same reactor. Understanding the effect of dose rate on radiation performance is important to predicting component lifetime. This study examined the effect of dose rate on swelling, grain boundary segregation, and tensile properties in austenitic stainless steels through the examination of components retrieved from the Experimental Breeder Reactor-II (EBR-II) following its shutdown. Annealed 304 stainless steel, stress-relieved 304 stainless steel, 12% cold-worked 316 stainless steel, and 20% cold-worked 316 stainless steel were irradiated over a dose range of 1-56 dpa at temperatures from 371 to 440 C and dose rates from 0.5 to 5.8 ? 10*7 dpa/s. Density and tensile properties were measured for 304 and 316 stainless steel. Changes in grain boundary composition were examined for 304 stainless steel. Swelling appears to increase at lower dose rates in both 304 and 316 stainless steel, although the effect was not always statistically significant. Grain boundary segregation also appears to increase at lower dose rate in 304 stainless steel. For the range of dose rates examined, no measurable dose rate effect on tensile properties was noted for any of the steels.

  16. Neutron irradiation creep in stainless steel alloys

    NASA Astrophysics Data System (ADS)

    Schüle, Wolfgang; Hausen, Hermann

    1994-09-01

    Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300°C and 500°C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of "primary" creep stage is observed for doses up to 3-5 dpa after which dose the "secondary" creep stage begins. The "primary" creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These "primary" creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of α-ferrite below about 400°C and of carbides below about 700°C, and not to irradiation creep. The "secondary" creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature ( Qirr = 0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels.

  17. Reducing tool wear when machining austenitic stainless steels

    SciTech Connect

    Magee, J.H.; Kosa, T.

    1998-07-01

    Austenitic stainless steels are considered more difficult to machine than carbon steels due to their high work hardening rate, large spread between yield and ultimate tensile strength, high toughness and ductility, and low thermal conductivity. These characteristics can result in a built-up edge or excessive tool wear during machining, especially when the cutting speed is too high. The practical solution is to lower the cutting speed until tool life reaches an acceptable level. However, lower machining speed negatively impacts productivity. Thus, in order to overcome tool wear at relatively high machining speeds for these alloys, on-going research is being performed to improve cutting fluids, develop more wear-resistant tools, and to modify stainless steels to make them less likely to cause tool wear. This paper discusses compositional modifications to the two most commonly machined austenitic stainless steels (Type 303 and 304) which reduced their susceptibility to tool wear, and allowed these grades to be machined at higher cutting speeds.

  18. Ultrasonic characterization of centrifugally cast stainless steel: Topical report

    SciTech Connect

    Jeong, P.

    1987-06-01

    Ultrasonic wave propagation in centrifugally cast stainless steel (CCSS) was investigated. The difficulties of inspecting CCSS material stem from elastic anisotropy that hampers defect location and severe attenuation caused by coarse grains within the structure that makes defect detection difficult. During this investigation, grain effects on ultrasonic wave propagation were investigated, techniques for identifying different grain structures were developed, and compensation methods for grain effects were addressed. Each step is explained analytically based on relevant theory and proven experimentally. Experiments were conducted on specially designed test specimens: angled blocks, polygonal blocks, wedge blocks, and calibration blocks. Wave parameters such as phase velocity, skew angle, energy velocity, attenuation, beam width, amplitude variation patterns, and frequency dependence on grain structures were all measured with these specimens. CCSS grain structures investigated were equiaxed-fine grains, columnar-dendritic grains, and coarse grains. For comparison purposes, additional types of material such as static-cast stainless steel, forged stainless steel, and carbon steel materials were also investigated. Longitudinal wave, horizontally and vertically polarized shear wave modes were all considered in experiments. The use of an automated ultrasonic system was also demonstrated for grain structure identification.

  19. A Comparative Study on Nd:YAG Laser Cutting of Steel and Stainless Steel Using Continuous, Square, and Sine Waveforms

    NASA Astrophysics Data System (ADS)

    Lo, K. H.

    2012-06-01

    Laser cutting with the sine waveform is seldom reported. This article is a comparative study on Nd:YAG laser cutting using the continuous (CW), square, and sine waveforms. The materials used in this study were steel and stainless steel. It has been found that the cutting capability, in descending order, is: CW > sine > square. The cutting of steel (C ~0.3 wt.%) and AISI304 austenitic stainless steel may be satisfactorily described by the Steen model, irrespective of waveform. Steel is slightly easier to cut than stainless steel. Limitations of the present study are discussed and suggestions for future work are made.

  20. Wear behavior of austenite containing plate steels

    NASA Astrophysics Data System (ADS)

    Hensley, Christina E.

    As a follow up to Wolfram's Master of Science thesis, samples from the prior work were further investigated. Samples from four steel alloys were selected for investigation, namely AR400F, 9260, Hadfield, and 301 Stainless steels. AR400F is martensitic while the Hadfield and 301 stainless steels are austenitic. The 9260 exhibited a variety of hardness levels and retained austenite contents, achieved by heat treatments, including quench and tempering (Q&T) and quench and partitioning (Q&P). Samples worn by three wear tests, namely Dry Sand/Rubber Wheel (DSRW), impeller tumbler impact abrasion, and Bond abrasion, were examined by optical profilometry. The wear behaviors observed in topography maps were compared to the same in scanning electron microscopy micrographs and both were used to characterize the wear surfaces. Optical profilometry showed that the scratching abrasion present on the wear surface transitioned to gouging abrasion as impact conditions increased (i.e. from DSRW to impeller to Bond abrasion). Optical profilometry roughness measurements were also compared to sample hardness as well as normalized volume loss (NVL) results for each of the three wear tests. The steels displayed a relationship between roughness measurements and observed wear rates for all three categories of wear testing. Nanoindentation was used to investigate local hardness changes adjacent to the wear surface. DSRW samples generally did not exhibit significant work hardening. The austenitic materials exhibited significant hardening under the high impact conditions of the Bond abrasion wear test. Hardening in the Q&P materials was less pronounced. The Q&T microstructures also demonstrated some hardening. Scratch testing was performed on samples at three different loads, as a more systematic approach to determining the scratching abrasion behavior. Wear rates and scratch hardness were calculated from scratch testing results. Certain similarities between wear behavior in scratch testing

  1. DETAIL VIEW OF STEEL PLATES IN WALKWAY CONNECTING NO. 3 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF STEEL PLATES IN WALKWAY CONNECTING NO. 3 TREATMENT SHOP (HIGH HOUSE) WITH NO. 2 TREATMENT SHOP - Bethlehem Steel Corporation, Along Lehigh River, North of Fourth Street, Bethlehem, Northampton County, PA

  2. Characterization of bulk stainless steel joints developed through microwave hybrid heating

    SciTech Connect

    Bansal, Amit; Sharma, Apurbba Kumar; Kumar, Pradeep; Das, Shantanu

    2014-05-01

    Processing of metallic materials through microwave heating is a challenging area of research. In the present work, joining of stainless steel-316 to stainless steel-316 in the bulk form has been carried out by placing stainless steel-316 powder at the interface and through targeted heating using microwave hybrid heating. The trials were carried out in a multimode microwave applicator at a frequency of 2.45 GHz and power 900 W. The developed joints were characterized using X-ray diffraction, field emission scanning electron microscopy equipped with energy dispersive X-ray spectroscope and measurement of Vicker's microhardness, porosity and tensile strength. The X-ray diffraction spectrum of the developed joint shows the presence of chromium carbide, iron carbide and iron silicide phases that eventually contribute to enhancement of the microhardness of the joint. The scanning electron microscope micrographs confirm classical metallurgical bonding between the substrate and the interface (molten powder) layer; the epitaxial growth rate was observed adjacent to the fusion zone. The average observed Vicker's microhardness in the joint zone on the grain boundary was significantly higher than that inside the grains due to the presence of various hard phases at the grain boundaries. Evaluation of the tensile strength of the joints showed an average ultimate tensile strength of 425.0 MPa with an average elongation of 9.44%. - Highlights: • Joining of stainless steel (SS-316) plates using microwave hybrid heating • Epitaxial growth rate observed adjacent to the fusion zone of welded joint • The ultimate tensile strength of the order of 425.0 MPa with 9.44% elongation.

  3. Hydrogen transport through stainless steel under plasma irradiation

    NASA Astrophysics Data System (ADS)

    Airapetov, A. A.; Begrambekov, L. B.; Kaplevsky, A. S.; Sadovskiy, Ya A.

    2016-01-01

    The paper presents the results of investigation of gas exchange through stainless steel surface of the plasma chamber under irradiation with hydrogen atoms in oxygen atmosphere or oxygen contaminated hydrogen plasma. Dependence of this process on various irradiation parameters, such as the metal temperature, energy of irradiating ions, gas composition of plasma are studied. It is shown, that desorption from stainless steel is activated with the increase of the plasma chamber walls temperature and energy of irradiating ions. Hydrogen release occurs also under irradiation of the walls by helium and argon plasmas added with oxygen, however the amount of released hydrogen is several times lower than in the case of irradiation with oxygen contaminated deuterium plasma.

  4. Failure Assessment of Stainless Steel and Titanium Brazed Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yury A.

    2012-01-01

    Following successful application of Coulomb-Mohr and interaction equations for evaluation of safety margins in Albemet 162 brazed joints, two additional base metal/filler metal systems were investigated. Specimens consisting of stainless steel brazed with silver-base filler metal and titanium brazed with 1100 Al alloy were tested to failure under combined action of tensile, shear, bending and torsion loads. Finite Element Analysis (FEA), hand calculations and digital image comparison (DIC) techniques were used to estimate failure stresses and construct Failure Assessment Diagrams (FAD). This study confirms that interaction equation R(sub sigma) + R(sub tau) = 1, where R(sub sigma) and R(sub t u) are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in stainless steel and titanium brazed joints.

  5. Inhibition of Sodium Benzoate on Stainless Steel in Tropical Seawater

    SciTech Connect

    Seoh, S. Y.; Senin, H. B.; Nik, W. N. Wan; Amin, M. M.

    2007-05-09

    The inhibition of sodium benzoate for stainless steel controlling corrosion was studied in seawater at room temperature. Three sets of sample have been immersed in seawater containing sodium benzoate with the concentrations of 0.3M, 0.6M and 1.0M respectively. One set of sample has been immersed in seawater without adding any sodium benzoate. It was found that the highest corrosion rate was observed for the stainless steel with no inhibitor was added to the seawater. As the concentration of sodium benzoate being increased, the corrosion rate is decreases. Results show that by the addition of 1.0M of sodium benzoate in seawater samples, it giving {>=} 90% efficiencies.

  6. STAINLESS STEEL INTERACTIONS WITH SALT CONTAINING PLUTONIUM OXIDES

    SciTech Connect

    Nelson, Z.; Chandler, G.; Dunn, K.; Stefek, T.; Summer, M.

    2010-02-01

    Salt containing plutonium oxide materials are treated, packaged and stored within nested, stainless steel containers based on requirements established in the DOE 3013 Standard. The moisture limit for the stored materials is less than 0.5 weight %. Surveillance activities which are conducted to assess the condition of the containers and assure continuing 3013 container integrity include the destructive examination of a select number of containers to determine whether corrosion attack has occurred as a result of stainless steel interactions with salt containing plutonium oxides. To date, some corrosion has been observed on the innermost containers, however, no corrosion has been noted on the outer containers and the integrity of the 3013 container systems is not expected to be compromised over a 50 year storage lifetime.

  7. Milling and Drilling Evaluation of Stainless Steel Powder Metallurgy Alloys

    SciTech Connect

    Lazarus, L.J.

    2001-12-10

    Near-net-shape components can be made with powder metallurgy (PM) processes. Only secondary operations such as milling and drilling are required to complete these components. In the past and currently production components are made from powder metallurgy (PM) stainless steel alloys. process engineers are unfamiliar with the difference in machining properties of wrought versus PM alloys and have had to make parts to develop the machining parameters. Design engineers are not generally aware that some PM alloy variations can be furnished with machining additives that greatly increase tool life. Specimens from a MANTEC PM alloy property study were made available. This study was undertaken to determine the machining properties of a number of stainless steel wrought and PM alloys under the same conditions so that comparisons of their machining properties could be made and relative tool life determined.

  8. Lifetest investigations with stainless steel/water heat pipes

    NASA Astrophysics Data System (ADS)

    Muenzel, W. D.; Kraehling, H.

    Life tests were conducted on water heat pipes, made from four different alloys of stainless steel, at operation temperatures of 120, 160, 220, and 320 C in a reflux boiler mode for more than 20,000 hr. Other parameters varied during the tests included capillary structure, pretreatment and cleaning of the components, additional oxidation of the inner surface, filling procedures, amoung of liquid change, the number of ventings, and the duration of the reaction runs. The best results were obtained with pipes containing stainless steels with molybdenum alloy additions and with carbon contents of greater than 0.03%; with components which formed a protective surface layer; with the use of double-distilled water that had been ultrasonically degassed; with repeated ventings during the initial reaction run of 500 hr minimum duration; and with the addition of gaseous oxygen into the heat pipe during the reaction run with subsequent venting.

  9. New hermetic sealing material for vacuum brazing of stainless steels

    NASA Astrophysics Data System (ADS)

    Hildebrandt, S.; Wiehl, G.; Silze, F.

    2016-03-01

    For vacuum brazing applications such as in vacuum interrupter industry Hermetic Sealing Materials (HSM) with low partial pressure are widely used. AgCu28 dominates the hermetic sealing market, as it has a very good wetting behavior on copper and metallized ceramics. Within recent decades wetting on stainless steel has become more and more important. However, today the silver content of HSMs is more in focus than in the past decades, because it has the biggest impact on the material prices. Umicore Technical Materials has developed a new copper based HSM, CuAg40Ga10. The wettability on stainless steel is significantly improved compared to AgCu28 and the total silver content is reduced by almost 44%. In this article the physical properties of the alloy and its brazed joints will be presented compared to AgCu28.

  10. Electrochemical Corrosion Testing of Borated Stainless Steel Alloys

    SciTech Connect

    lister, tedd e; Mizia, Ronald E

    2007-05-01

    The Department of Energy Office of Civilian Radioactive Waste Management has specified borated stainless steel manufactured to the requirements of ASTM A 887-89, Grade A, UNS S30464, to be the material used for the fabrication of the fuel basket internals of the preliminary transportation, aging, and disposal canister system preliminary design. The long-term corrosion resistance performance of this class of borated materials must be verified when exposed to expected YMP repository conditions after a waste package breach. Electrochemical corrosion tests were performed on crevice corrosion coupons of Type 304 B4 and Type 304 B5 borated stainless steels exposed to single postulated in-package chemistry at 60°C. The results show low corrosion rates for the test period

  11. Electrochemical Corrosion Testing of Borated Stainless Steel Alloys

    SciTech Connect

    lister, tedd e; Mizia, Ronald E

    2007-09-01

    The Department of Energy Office of Civilian Radioactive Waste Management has specified borated stainless steel manufactured to the requirements of ASTM A 887-89, Grade A, UNS S30464, to be the material used for the fabrication of the fuel basket internals of the preliminary transportation, aging, and disposal canister system preliminary design. The long-term corrosion resistance performance of this class of borated materials must be verified when exposed to expected YMP repository conditions after a waste package breach. Electrochemical corrosion tests were performed on crevice corrosion coupons of Type 304 B4 and Type 304 B5 borated stainless steels exposed to single postulated in-package chemistry at 60°C. The results show low corrosion rates for the test period

  12. The technology of chromium oxide passivation on stainless steel surface

    SciTech Connect

    Ohmi, Tadahiro; Ohki, Atsushi; Nakamura, Masakazu; Kawada, Koji; Watanabe, Tsuyoshi; Nakagawa, Yoshinori; Miyoshi, Shinji; Takahashi, Shinji; Chen, M.S.K. . Dept. of Electronics)

    1993-06-01

    A complete chromium oxide (Cr[sub 2]O[sub 3]) passivation technology has been developed for stainless steel surfaces for use in high purity gas-delivery systems and process chambers. Starting with an electrochemical buffing (ECB) to add to electro-polished (EP) SUS316L stainless steel material, an optimal thermal treatment was found by using a gas mixture of 10% hydrogen, 1--10 ppm oxygen and argon balance gas at 500C for 1 h. Five-day corrosion tests with HCl gas (containing 1.4 ppm moisture) at 5 kg/cm[sup 2] and 100C showed no sign of corrosion on the chromium oxide passivated surface. Chemical stability tests on this surface with silane specialty gas thermal decomposition also showed a remarkable noncatalytic activity compared with conventional surfaces.

  13. Duplex stainless steels for the pulp and paper industry

    SciTech Connect

    Alfonsson, E.; Olsson, J.

    1999-07-01

    The metallurgy and corrosion resistance of duplex stainless steel, particularly with regards to applications in the pulp and paper industry, are described. Practical experiences from pressure vessel installations in cooking plants and bleach plants as well as from non-pressurized items in different parts along the fiber line, are given. The paper also reviews corrosion test results presented previously and compares these with recent test data and the practical experiences. Though most of the installations have been successful, some cases of corrosion attacks on duplex stainless steel have been reported, although these are very limited in number: one digester, one calorifier, two pulp storage towers, and two bleach plant filter washers, of a total of more than 700 identified installations.

  14. Investigation of Laser Peening Effects on Hydrogen Charged Stainless Steels

    SciTech Connect

    Zaleski, Tania M.

    2008-10-30

    Hydrogen-rich environments such as fuel cell reactors can exhibit damage caused by hydrogen permeation in the form of corrosion cracking by lowering tensile strength and decreasing material ductility. Coatings and liners have been investigated, but there were few shot-peening or laser peening studies referenced in the literature with respect to preventing hydrogen embrittlement. The surface compressive residual stress induced by laser peening had shown success in preventing stress corrosion cracking (SCC) for stainless steels in power plants. The question arose if the residual stresses induced by laser peening could delay the effects of hydrogen in a material. This study investigated the effect of laser peening on hydrogen penetration into metal alloys. Three areas were studied: laser peening, hydrogenation, and hydrogen detection. This study demonstrated that laser peening does not reduce the hydrogen permeation into a stainless steel surface nor does it prevent hydrogen embrittlement. The effect of laser peening to reduce hydrogen-assisted fatigue was unclear.

  15. Sensitization and IGSCC susceptibility prediction in stainless steel pipe weldments

    SciTech Connect

    Atteridge, D.G.; Simmons, J.W.; Li, Ming; Bruemmer, S.M.

    1991-11-01

    An analytical model, based on prediction of chromium depletion, has been developed for predicting thermomechanical effects on austenitic stainless steel intergranular stress corrosion cracking (IGSCC) susceptibility. Model development and validation is based on sensitization development analysis of over 30 Type 316 and 304 stainless steel heats. The data base included analysis of deformation effects on resultant sensitization development. Continuous Cooling sensitization behavior is examined and modelled with and without strain. Gas tungsten are (GTA) girth pipe weldments are also characterized by experimental measurements of heat affected zone (HAZ) temperatures, strains and sensitization during/after each pass; pass by pass thermal histories are also predicted. The model is then used to assess pipe chemistry changes on IGSCC resistance.

  16. Development of a compact laminar flow heat exchanger with stainless steel micro-tubes

    NASA Astrophysics Data System (ADS)

    Saji, N.; Nagai, S.; Tsuchiya, K.; Asakura, H.; Obata, M.

    2001-05-01

    The present paper describes the design concept and manufacturing of a new compact laminar flow heat exchanger with stainless-steel micro-tubes for helium refrigerators. In the temperature range of less than 20 K, aluminum plate fin type heat exchangers exhibit a remarkable fall of performance characteristics as a compact heat exchanger. We presented in a previous paper that some compact heat exchangers with good performance in the temperature range of less than 4 K are required for a subcooled He II refrigerator cycle to be worked with 3He turbo-compressors (F. Doty, et al., A new look at the closed brayton cycle, Proceedings, IECEC-90 Reno, NV, 1991, p. 116). For this requirement, we developed a micro-tube strip counter flow type heat exchanger, which consists of 12 elements with a total of 4800 stainless steel micro-tubes. Each element is formed with 400 tubes and a newly developed vacuum brazing method was applied for the bonding to the side plate. Each tube has an inner diameter of 0.5 mm, an outer diameter of 0.7 mm and is 310 mm long. We developed a cladding plate with two layers of gold brazing sheet sandwiched inside. In aerodynamic and thermal design of the element, the laminar flow conditions were adopted for the flows of inner and outer tubes to keep a high heat transfer rate and a low pressure loss.

  17. SELECTIVE SEPARATION OF URANIUM FROM FERRITIC STAINLESS STEELS

    DOEpatents

    Beaver, R.J.; Cherubini, J.H.

    1963-05-14

    A process is described for separating uranium from a nuclear fuel element comprising a uranium-containing core and a ferritic stainless steel clad by heating said element in a non-carburizing atmosphere at a temperature in the range 850-1050 un. Concent 85% C, rapidly cooling the heated element through the temperature range 815 un. Concent 85% to 650 EC to avoid annealing said steel, and then contacting the cooled element with an aqueous solution of nitric acid to selectively dissolve the uranium. (AEC)

  18. Surface nanocrystallization of stainless steel for reduced biofilm adherence.

    PubMed

    Yu, Bin; Davis, Elisabeth M; Hodges, Robert S; Irvin, Randall T; Li, D Y

    2008-08-20

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm's adherence to stainless steel. During this treatment, a target surface was sandblasted and the resultant dislocation cells in the surface layer were turned into nanosized grains by a subsequent recovery treatment in air. This process generated a more protective oxide film that blocked the electron exchange or reduced the surface activity more effectively. As a result, the biofilm's adherence to the treated surface was markedly minimized. A synthetic peptide was utilized as a substitute of biofilms to evaluate the adhesion between a treated steel surface and biofilms using an atomic force microscope (AFM) through measuring the adhesive force between the target surface and a peptide-coated AFM tip. It was shown that the adhesive force decreased with a decrease in the grain size of the steel. The corresponding surface electron work function (EWF) of the steel was also measured, which showed a trend of variation in EWF with the grain size, consistent with corresponding changes in the adhesive force. PMID:21730615

  19. Surface nanocrystallization of stainless steel for reduced biofilm adherence

    NASA Astrophysics Data System (ADS)

    Yu, Bin; Davis, Elisabeth M.; Hodges, Robert S.; Irvin, Randall T.; Li, D. Y.

    2008-08-01

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm's adherence to stainless steel. During this treatment, a target surface was sandblasted and the resultant dislocation cells in the surface layer were turned into nanosized grains by a subsequent recovery treatment in air. This process generated a more protective oxide film that blocked the electron exchange or reduced the surface activity more effectively. As a result, the biofilm's adherence to the treated surface was markedly minimized. A synthetic peptide was utilized as a substitute of biofilms to evaluate the adhesion between a treated steel surface and biofilms using an atomic force microscope (AFM) through measuring the adhesive force between the target surface and a peptide-coated AFM tip. It was shown that the adhesive force decreased with a decrease in the grain size of the steel. The corresponding surface electron work function (EWF) of the steel was also measured, which showed a trend of variation in EWF with the grain size, consistent with corresponding changes in the adhesive force.

  20. Aluminum/steel wire composite plates exhibit high tensile strength

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Composite plate of fine steel wires imbedded in an aluminum alloy matrix results in a lightweight material with high tensile strength. Plates have been prepared having the strength of titanium with only 85 percent of its density.

  1. Cryogenic thermal absorptance measurements on small-diameter stainless steel tubing

    NASA Astrophysics Data System (ADS)

    Tuttle, James; Jahromi, Amir; Canavan, Edgar; DiPirro, Michael

    2016-03-01

    The Mid Infrared Instrument (MIRI) on the James Webb Space Telescope includes a mechanical cryocooler which cools its detectors to their 6 K operating temperature. The coolant gas flows through several meters of small-diameter stainless steel tubing, which is exposed to thermal radiation from its environment. Over much of its length this tubing is gold-plated to minimize the absorption of this radiant heat. In order to confirm that the cryocooler will meet MIRI's requirements, the thermal absorptance of this tubing was measured as a function of its environment temperature. We describe the measurement technique and present the results.

  2. Ion beam nitriding of single and polycrystalline austenitic stainless steel

    SciTech Connect

    Abrasonis, G.; Riviere, J.P.; Templier, C.; Declemy, A.; Pranevicius, L.; Milhet, X.

    2005-04-15

    Polycrystalline and single crystalline [orientations (001) and (011)] AISI 316L austenitic stainless steel was implanted at 400 deg. C with 1.2 keV nitrogen ions using a high current density of 0.5 mA cm{sup -2}. The nitrogen distribution profiles were determined using nuclear reaction analysis (NRA). The structure of nitrided polycrystalline stainless steel samples was analyzed using glancing incidence and symmetric x-ray diffraction (XRD) while the structure of the nitrided single crystalline stainless steel samples was analyzed using x-ray diffraction mapping of the reciprocal space. For identical treatment conditions, it is observed that the nitrogen penetration depth is larger for the polycrystalline samples than for the single crystalline ones. The nitrogen penetration depth depends on the orientation, the <001> being more preferential for nitrogen diffusion than <011>. In both type of samples, XRD analysis shows the presence of the phase usually called 'expanded' austenite or {gamma}{sub N} phase. The lattice expansion depends on the crystallographic plane family, the (001) planes showing an anomalously large expansion. The reciprocal lattice maps of the nitrided single crystalline stainless steel demonstrate that during nitriding lattice rotation takes place simultaneously with lattice expansion. The analysis of the results based on the presence of stacking faults, residual compressive stress induced by the lattice expansion, and nitrogen concentration gradient indicates that the average lattice parameter increases with the nitrided layer depth. A possible explanation of the anomalous expansion of the (001) planes is presented, which is based on the combination of faster nitriding rate in the (001) oriented grains and the role of stacking faults and compressive stress.

  3. Manganese-stabilized austenitic stainless steels for fusion applications

    DOEpatents

    Klueh, Ronald L.; Maziasz, Philip J.

    1990-01-01

    An austenitic stainless steel that is comprised of Fe, Cr, Mn, C but no Ni or Nb and minimum N. To enhance strength and fabricability minor alloying additions of Ti, W, V, B and P are made. The resulting alloy is one that can be used in fusion reactor environments because the half-lives of the elements are sufficiently short to allow for handling and disposal.

  4. Manganese-stabilized austenitic stainless steels for fusion applications

    DOEpatents

    Klueh, Ronald L.; Maziasz, Philip J.

    1990-08-07

    An austenitic stainless steel that is comprised of Fe, Cr, Mn, C but no Ni or Nb and minimum N. To enhance strength and fabricability minor alloying additions of Ti, W, V, B and P are made. The resulting alloy is one that can be used in fusion reactor environments because the half-lives of the elements are sufficiently short to allow for handling and disposal.

  5. Attack polish for nickel-base alloys and stainless steels

    DOEpatents

    Steeves, Arthur F.; Buono, Donald P.

    1983-01-01

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels. The chemical attack polish comprises Fe(NO.sub.3).sub.3, concentrated CH.sub.3 COOH, concentrated H.sub.2 SO.sub.4 and H.sub.2 O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  6. Method of polishing nickel-base alloys and stainless steels

    DOEpatents

    Steeves, Arthur F.; Buono, Donald P.

    1981-01-01

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels. The chemical attack polish comprises Fe(NO.sub.3).sub.3, concentrated CH.sub.3 COOH, concentrated H.sub.2 SO.sub.4 and H.sub.2 O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  7. Fatigue crack propagation behavior of stainless steel welds

    NASA Astrophysics Data System (ADS)

    Kusko, Chad S.

    The fatigue crack propagation behavior of austenitic and duplex stainless steel base and weld metals has been investigated using various fatigue crack growth test procedures, ferrite measurement techniques, light optical microscopy, stereomicroscopy, scanning electron microscopy, and optical profilometry. The compliance offset method has been incorporated to measure crack closure during testing in order to determine a stress ratio at which such closure is overcome. Based on this method, an empirically determined stress ratio of 0.60 has been shown to be very successful in overcoming crack closure for all da/dN for gas metal arc and laser welds. This empirically-determined stress ratio of 0.60 has been applied to testing of stainless steel base metal and weld metal to understand the influence of microstructure. Regarding the base metal investigation, for 316L and AL6XN base metals, grain size and grain plus twin size have been shown to influence resulting crack growth behavior. The cyclic plastic zone size model has been applied to accurately model crack growth behavior for austenitic stainless steels when the average grain plus twin size is considered. Additionally, the effect of the tortuous crack paths observed for the larger grain size base metals can be explained by a literature model for crack deflection. Constant Delta K testing has been used to characterize the crack growth behavior across various regions of the gas metal arc and laser welds at the empirically determined stress ratio of 0.60. Despite an extensive range of stainless steel weld metal FN and delta-ferrite morphologies, neither delta-ferrite morphology significantly influence the room temperature crack growth behavior. However, variations in weld metal da/dN can be explained by local surface roughness resulting from large columnar grains and tortuous crack paths in the weld metal.

  8. Attack polish for nickel-base alloys and stainless steels

    DOEpatents

    Not Available

    1980-05-28

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels is described. The chemical attack polich comprises FeNO/sub 3/, concentrated CH/sub 3/COOH, concentrated H/sub 2/SO/sub 4/ and H/sub 2/O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  9. Comparison of photodesorption yields from aluminum stainless and Cu-plated beam tubes

    SciTech Connect

    Halama, H.J.; Foerster, C.L.

    1989-01-01

    Photon Stimulated Desorption (PSD) from the walls of beam ducts constitutes the most serious gas load in storage rings and therefore exerts a great influence on both beam quality and lifetime. With the exception of the SSC which plans to use a Cu-plated beam tube, all existing and proposed machines use either aluminum or stainless steel beam tubes. In order to develop techniques for producing surfaces with the lowest PSD, we have studied the above materials using a dedicated beam line at the National Synchrotron Light Source (NSLS). Three meter long tubes were exposed to white light beams having critical energy of 500 eV and the desorption yields were measured as a function of beam dose. Several treatments commonly used for cleaning surfaces (prebaked, baked, fired, chemically cleaned and dc glow discharged) were investigated, and their relative merits are discussed. The results from sample tube measurements are compared with those from the X-rya ring Al beam tube during operation. The agreement is found to be quite good. Glow discharge cleaned stainless steel exhibited the lowest desorption yield. 7 refs., 9 figs.

  10. 46 CFR 148.04-13 - Ferrous metal borings, shavings, turnings, or cuttings (excluding stainless steel).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (excluding stainless steel). 148.04-13 Section 148.04-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND... stainless steel). (a) This section applies to the stowage and transportation in bulk of hazardous materials... steel). However, unmanned barges on which the article is stowed for or transported on a voyage...

  11. 75 FR 39663 - Stainless Steel Bar From Brazil: Final Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-12

    ... Antidumping Duty Administrative Review, 73 FR 75398, 75399 (December 11, 2008), and Stainless Steel Sheet and... Steel Bar From Brazil, 59 FR 66914 (December 28, 1994). These deposit requirements shall remain in... International Trade Administration Stainless Steel Bar From Brazil: Final Results of Antidumping...

  12. 75 FR 54090 - Stainless Steel Bar From India: Final Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... Steel Bar from India, 59 FR 66915 (December 28, 1994). These cash deposit requirements, when imposed... International Trade Administration Stainless Steel Bar From India: Final Results of Antidumping Duty... results of the administrative review of the antidumping duty order on stainless steel bar (``SSB'')...

  13. Recrystallization and Grain Growth of 316L Stainless Steel Wires

    NASA Astrophysics Data System (ADS)

    Zhao, Xiuyun; Liu, Yong; Wang, Yan; Feng, Ping; Tang, Huiping

    2014-07-01

    Recrystallization and grain growth behaviors of 316L stainless steel wires with a diameter of 12 µm were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy (TEM), and X-ray diffraction techniques. Heavily cold-drawn wires were isothermally held at temperatures from 1073 K to 1223 K (800 °C to 950 °C) for various holding times. Optical microscopy and TEM observations showed that recrystallization grains have irregular shape and that twins exist. The texture formed during drawing and annealing processes of the wires, as measured by X-ray methods, showed a fiber texture approximated by a <111> and a <100> component. The value of the grain growth exponent n was calculated, and the kinetic rates were plotted using the Arrhenius equation. Results show that the activation energy of the grain growth for 316L stainless steel wire was determined to be 407 kJ/mol, which was much higher than that of the bulk 316L stainless steel. The small wire diameter and the existence of texture played important roles in the increase of the activation energy for grain growth of the wire.

  14. Surface interactions of cesium and boric acid with stainless steel

    SciTech Connect

    Grossman-Canfield, N.

    1995-08-01

    In this report, the effects of cesium hydroxide and boric acid on oxidized stainless steel surfaces at high temperatures and near one atmosphere of pressure are investigated. This is the first experimental investigation of this chemical system. The experimental investigations were performed using a mass spectrometer and a mass electrobalance. Surfaces from the different experiments were examined using a scanning electron microscope to identify the presence of deposited species, and electron spectroscopy for chemical analysis to identify the species deposited on the surface. A better understanding of the equilibrium thermodynamics, the kinetics of the steam-accelerated volatilizations, and the release kinetics are gained by these experiments. The release rate is characterized by bulk vaporization/gas-phase mass transfer data. The analysis couples vaporization, deposition, and desorption of the compounds formed by cesium hydroxide and boric acid under conditions similar to what is expected during certain nuclear reactor accidents. This study shows that cesium deposits on an oxidized stainless steel surface at temperatures between 1000 and 1200 Kelvin. Cesium also deposits on stainless steel surfaces coated with boric oxide in the same temperature ranges. The mechanism for cesium deposition onto the oxide layer was found to involve the chemical reaction between cesium and chromate. Some revaporization in the cesium hydroxide-boric acid system was observed. It has been found that under the conditions given, boric acid will react with cesium hydroxide to form cesium metaborate. A model is proposed for this chemical reaction.

  15. Thermal Aging Phenomena in Cast Duplex Stainless Steels

    NASA Astrophysics Data System (ADS)

    Byun, T. S.; Yang, Y.; Overman, N. R.; Busby, J. T.

    2016-02-01

    Cast stainless steels (CASSs) have been extensively used for the large components of light water reactor (LWR) power plants such as primary coolant piping and pump casing. The thermal embrittlement of CASS components is one of the most serious concerns related to the extended-term operation of nuclear power plants. Many past researches have concluded that the formation of Cr-rich α'-phase by Spinodal decomposition of δ-ferrite phase is the primary mechanism for the thermal embrittlement. Cracking mechanism in the thermally-embrittled duplex stainless steels consists of the formation of cleavage at ferrite and its propagation via separation of ferrite-austenite interphase. This article intends to provide an introductory overview on the thermal aging phenomena in LWR-relevant conditions. Firstly, the thermal aging effect on toughness is discussed in terms of the cause of embrittlement and influential parameters. An approximate analysis of thermal reaction using Arrhenius equation was carried out to scope the aging temperatures for the accelerated aging experiments to simulate the 60 and 80 years of services. Further, an equilibrium precipitation calculation was performed for model CASS alloys using the CALPHAD program, and the results are used to describe the precipitation behaviors in duplex stainless steels. These results are also to be used to guide an on-going research aiming to provide knowledge-based conclusive prediction for the integrity of the CASS components of LWR power plants during the service life extended up to and beyond 60 years.

  16. Impact Testing of Stainless Steel Material at Cold Temperatures

    SciTech Connect

    Spencer D. Snow; D. Keith Morton; Robert K. Blandford

    2008-07-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates during accidental drop events. Mechanical characteristics of these base materials and their welds under dynamic loads in the strain rate range of concern are not well documented. However, a previous paper [1] reported on impact testing and analysis results performed at the Idaho National Laboratory using 304/304L and 316/316L stainless steel base material specimens at room and elevated temperatures. The goal of the work presented herein is to add recently completed impact tensile testing results at -20 degrees F conditions for dual-marked 304/304L and 316/316L stainless steel material specimens (hereafter referred to as 304L and 316L, respectively). Recently completed welded material impact testing at -20 degrees F, room, 300 degrees F, and 600 degrees F is also reported. Utilizing a drop-weight impact test machine and 1/4-inch to 1/2-inch thick dog-bone shaped test specimens, the impact tests achieved strain rates in the 4 to 40 per second range, depending upon the material temperature. Elevated true stress-strain curves for these materials reflecting varying strain rates and temperatures are presented herein.

  17. Iodine susceptibility of pseudomonads grown attached to stainless steel surfaces

    NASA Technical Reports Server (NTRS)

    Pyle, B. H.; McFeters, G. A.

    1990-01-01

    Pseudomonads were adapted to grow in phosphate-buffered water and on stainless steel surfaces to study the iodine sensitivity of attached and planktonic cells. Cultures adapted to low nutrient growth were incubated at room temperature in a circulating reactor system with stainless steel coupons to allow biofilm formation on the metal surfaces. In some experiments, the reactor was partially emptied and refilled with buffer at each sampling time to simulate a "fill-and-draw" water system. Biofilms of attached bacteria, resuspended biofilm bacteria, and reactor suspension, were exposed to 1 mg l-1 iodine for 2 min. Attached bacterial populations which established on coupons within 3 to 5 days displayed a significant increase in resistance to iodine. Increased resistance was also observed for resuspended cells from the biofilm and planktonic bacteria in the system suspension. Generally, intact biofilms and resuspended biofilm cells were most resistant, followed by planktonic bacteria and phosphate buffer cultures. Thus, biofilm formation on stainless steel surfaces within water systems can result in significantly increased disinfection resistance of commonly-occurring water-borne bacteria that may enhance their ability to colonise water treatment and distribution systems.

  18. Stress corrosion cracking evaluation of martensitic precipitation hardening stainless steels

    NASA Technical Reports Server (NTRS)

    Humphries, T. S.; Nelson, E. E.

    1980-01-01

    The resistance of the martensitic precipitation hardening stainless steels PH13-8Mo, 15-5PH, and 17-4PH to stress corrosion cracking was investigated. Round tensile and c-ring type specimens taken from several heats of the three alloys were stressed up to 100 percent of their yield strengths and exposed to alternate immersion in salt water, to salt spray, and to a seacoast environment. The results indicate that 15-5PH is highly resistant to stress corrosion cracking in conditions H1000 and H1050 and is moderately resistant in condition H900. The stress corrosion cracking resistance of PH13-8Mo and 17-4PH stainless steels in conditions H1000 and H1050 was sensitive to mill heats and ranged from low to high among the several heats included in the tests. Based on a comparison with data from seacoast environmental tests, it is apparent that alternate immersion in 3.5 percent salt water is not a suitable medium for accelerated stress corrosion testing of these pH stainless steels.

  19. Corrosion Performance of Stainless Steels in a Simulated Launch Environment

    NASA Technical Reports Server (NTRS)

    Calle, Luz Marina; Vinje, Rubiela D.; MacDowell, Louis

    2004-01-01

    At the Kennedy Space Center, NASA relies on stainless steel (SS) tubing to supply the gases and fluids required to launch the Space Shuttle. 300 series SS tubing has been used for decades but the highly corrosive environment at the launch pad has proven to be detrimental to these alloys. An upgrade with higher alloy content materials has become necessary in order to provide a safer and long lasting launch facility. In the effort to find the most suitable material to replace the existing AISI 304L SS ([iNS S30403) and AISI 316L SS (UNS S31603) shuttle tubing, a study involving atmospheric exposure at the corrosion test site near the launch pads and electrochemical measurements is being conducted. This paper presents the results of an investigation in which stainless steels of the 300 series, 304L, 316L, and AISI 317L SS (UNS S31703) as well as highly alloyed stainless steels 254-SMO (UNS S32154), AL-6XN (N08367) and AL29-4C ([iNS S44735) were evaluated using direct current (DC) electrochemical techniques under conditions designed to simulate those found at the Space Shuttle Launch pad. The electrochemical results were compared to the atmospheric exposure data and evaluated for their ability to predict the long-term corrosion performance of the alloys.

  20. Thermo-mechanical behavior of stainless steel knitted structures

    NASA Astrophysics Data System (ADS)

    Hamdani, Syed Talha Ali; Fernando, Anura; Maqsood, Muhammad

    2015-11-01

    Heating fabric is an advanced textile material that is extensively researched by the industrialists and the scientists alike. Ability to create highly flexible and drapeable heating fabrics has many applications in everyday life. This paper presents a study conducted on the comparison of heatability of knitted fabric made of stainless steel yarn. The purpose of the study is to find a suitable material for protective clothing against cold environments. In the current research the ampacity of stainless steel yarn is observed in order to prevent the overheating of the heating fabrics. The behavior of the knitted structure is studied for different levels of supply voltage. Infrared temperature sensing is used to measure the heat generated from the fabrics in order to measure the temperature of the fabrics without physical contact. It is concluded that interlock structure is one of the most suited structures for knitted heating fabrics. As learnt through this research, fabrics made of stainless steel yarn are capable of producing a higher level of heating compared to that of knitted fabric made using silver coated polymeric yarn at the same supply voltage.

  1. Recombination coefficients of O and N radicals on stainless steel

    NASA Astrophysics Data System (ADS)

    Singh, Harmeet; Coburn, J. W.; Graves, David B.

    2000-09-01

    Surface recombination coefficients of O and N radicals in pure O2 and N2 plasmas, respectively, have been estimated on the stainless steel walls of a low-pressure inductively coupled plasma reactor. The recombination coefficients are estimated using a steady state plasma model describing the balance between the volume generation of the radicals from electron-impact dissociation of the parent molecules, and the loss of the radicals due to surface recombination. The model uses radical and parent molecule number densities and the electron energy distribution function (EEDF) as input parameters. We have measured the radical number density using appearance potential mass spectrometry. The parent neutral number density is measured using mass spectrometry. The EEDF is measured using a Langmuir probe. The recombination coefficient of O radicals on stainless steel walls at approximately 330 K is estimated to be 0.17±0.02, and agrees well with previous measurements. The recombination coefficient of N radicals is estimated to be 0.07±0.02 on stainless steel at 330 K.

  2. Compatibility Assessment of Advanced Stainless Steels in Sodium

    SciTech Connect

    Pawel, Steven J

    2012-01-01

    Type 316L stainless steel capsules containing commercially pure sodium and miniature tensile specimens of HT-UPS (austenitic, 14Cr-16Ni), NF-616 (ferritic/martensitic, 9Cr-2W-0.5Mo), or 316L (austenitic, 17Cr-10Ni-2Mo) stainless steel were exposed at 600 or 700 C for 100 and 400 h as a screening test for compatibility. Using weight change, tensile testing, and metallographic analysis, HT-UPS and 316L were found to be largely immune to changes resulting from sodium exposure, but NF-616 was found susceptible to substantial decarburization at 700 C. Subsequently, two thermal convection loops (TCLs) constructed of 316L and loaded with commercially pure sodium and miniature tensile specimens of HT-UPS and 316L were operated for 2000 h each one between 500 and 650 C, the other between 565 and 725 C at a flow rate of about 1.5 cm/s. Changes in specimen appearance, weight, and tensile properties were observed to be very minor in all cases, and there was no metallographic evidence of microstructure changes, composition gradients, or mass transfer resulting from prolonged exposure in a TCL. Thus, it appears that HT-UPS and 316L stainless steels are similarly compatible with commercially pure sodium under these exposure conditions.

  3. Corrosion of stainless steel for HLW containers under gamma irradiation

    SciTech Connect

    Osada, K.; Muraoka, S.

    1993-12-31

    The corrosion behavior of type 304 stainless steel was studied under gamma irradiation as part of the evaluation for the long-term durability of high-level radioactive waste (HLW) disposal containers. Gamma rays, generated from fission products in high-level radioactive waste, are considered to change the environment around the canisters and overpacks. The redox potentials for NaCl solutions and corrosion potentials of stainless steel were measured to consider the effects of gamma irradiation, by using an electrochemical method. The pitting potentials of stainless steel for NaCl solutions were also measured to examine the pitting corrosion under gamma irradiation. As a result of this experiment, it is concluded that the oxidizing properties as a result of the formation of H{sub 2}O{sub 2} and H{sub 2} produced by gamma irradiation depended on the concentration of Cl{sup -}, and that the strength of oxidizing properties of 1M (mol{center_dot}dm{sup -3}) NaCl solution was particularly high, and the pitting corrosion as found for 1M NaCl solution under gamma irradiation at the dose rate of 2.6{times}10{sup 2} C/kg{center_dot}h (1.0{times}10{sup 6} R/h) at 60{degrees}C, by using an electrochemical method.

  4. Adsorption of ammonia on treated stainless steel and polymer surfaces

    NASA Astrophysics Data System (ADS)

    Vaittinen, O.; Metsälä, M.; Persijn, S.; Vainio, M.; Halonen, L.

    2014-05-01

    Adsorption of dynamically diluted ammonia at part-per-billion to low part-per-million concentrations in dry nitrogen was studied with treated and non-treated stainless steel and polymer test tubes. The treatments included electropolishing and two types of coatings based on amorphous silicon. Cavity ring-down spectroscopy with an external cavity diode laser operating in the near-infrared wavelength range was used to monitor the adsorption process in real time in continuous-flow conditions to obtain quantitative assessment of the adsorptive properties of the studied surfaces. The investigated polymers were all less adsorptive than any of the treated or non-treated stainless steel surfaces. Some of the commercial coatings reduced the adsorption loss of stainless steel by a factor of ten or more. Polyvinylidene fluoride was found to be superior (less adsorption) to the four other studied polymer coatings. The number of adsorbed ammonia molecules per surface area obtained at different ammonia gas phase concentrations was modeled with Langmuir and Freundlich isotherms. The time behavior of the adsorption-desorption process occurring in the time scale of seconds and minutes was simulated with a simple kinetic model.

  5. Thermal Aging Phenomena in Cast Duplex Stainless Steels

    SciTech Connect

    Byun, T. S.; Yang, Y.; Overman, N. R.; Busby, J. T.

    2015-11-12

    We used cast stainless steels (CASSs)for the large components of light water reactor (LWR) power plants such as primary coolant piping and pump casing. The thermal embrittlement of CASS components is one of the most serious concerns related to the extended-term operation of nuclear power plants. Many past researches have concluded that the formation of Cr-rich alpha-phase by Spinodal decomposition of delta-ferrite phase is the primary mechanism for the thermal embrittlement. Cracking mechanism in the thermally-embrittled duplex stainless steels consists of the formation of cleavage at ferrite and its propagation via separation of ferrite-austenite interphase. This article intends to provide an introductory overview on the thermal aging phenomena in LWR-relevant conditions. Firstly, the thermal aging effect on toughness is discussed in terms of the cause of embrittlement and influential parameters. Moreover, an approximate analysis of thermal reaction using Arrhenius equation was carried out to scope the aging temperatures for the accelerated aging experiments to simulate the 60 and 80 years of services. Further, an equilibrium precipitation calculation was performed for model CASS alloys using the CALPHAD program, and the results are used to describe the precipitation behaviors in duplex stainless steels. Our results are also to be used to guide an on-going research aiming to provide knowledge-based conclusive prediction for the integrity of the CASS components of LWR power plants during the service life extended up to and beyond 60 years.

  6. Evaluation of manual ultrasonic inspection of cast stainless steel piping

    SciTech Connect

    Taylor, T.T.

    1984-05-01

    Two studies have attempted to determine the degree of inspectability of centrifugally cast stainless steel (CCSS) pipe. In one study, Westinghouse examined the reliability of ultrasonic test methods in the detection of mechanical fatigue cracks. The second study was an NRC-sponsored Pipe Inspection Round Robin (PIRR) test conducted at Pacific Northwest Laboratory (PNL). The Westinghouse study reported that 80% detection was achieved for mechanical fatigue cracks having 20% throughwall depth. The PNL study reported that less than 30% detection was achieved for thermal fatigue cracks ranging from 5% to 50% through-wall. A cooperative program between PNL and Westinghouse was conducted to resolve the differences between the two studies. The program was designed as a limited round robin. Detection experiments were performed on samples from both the PNL and Westinghouse studies. The data reported here indicate that flaw type (thermal fatigue versus mechanical fatigue) was a significant factor in detection. Mechanical fatigue cracks were more easily detected than thermal fatigue cracks. The data conclusively show that manual ultrasonic inspection cannot size flaws in cast stainless steel material. The study recommends that ultrasonic inspection of cast stainless steel pipe be continued because cracks caused by some failure mechanisms (i.e., mechanical fatigue cracks) have proven to be detectable.

  7. Mechanical Behavior and Fractography of 304 Stainless Steel with High Hydrogen Concentration

    SciTech Connect

    Au, M.

    2003-02-05

    Hydrogen embrittlement of 304 stainless steel with different hydrogen concentrations has been investigated. An electrochemical technique was used to effectively charge the high level of hydrogen into 304 stainless steel in a short period of time. At 25 ppm of hydrogen, 304 stainless steel loses 10 percent of its original mechanical strength and 20 percent plasticity. Although the ductile feature dominates the fractography, the brittle crown area near the outer surface shows the intergranular rupture effected by hydrogen. At 60 ppm of hydrogen, 304 stainless steel loses 23 percent of its strength and 38 percent plasticity, where the brittle mode dominates the fracture of the materials. Experimental results show that hydrogen damage to the performance of 304 stainless steel is significant even at very low levels. The fractograph analysis indicates the high penetration ability of hydrogen in 304 stainless steel. This work also demonstrates the advantages of the electrochemical charging technique in the study of hydrogen embrittlement.

  8. Mechanical properties of thermally aged cast stainless steels from Shippingport reactor components

    SciTech Connect

    Chopra, O.K.; Shack, W.J.

    1995-04-01

    Thermal embrittlement of static-cast CF-8 stainless steel components from the decommissioned Shippingport reactor has been characterized. Cast stainless steel materials were obtained from four cold-leg check valves, three hot-leg main shutoff valves, and two pump volutes. The actual time-at-temperature for the materials was {approximately}13 y at {approximately}281 C (538 F) for the hot-leg components and {approximately}264 C (507 F) for the cold-leg components. Baseline mechanical properties for as-cast material were determined from tests on either recovery-annealed material, i.e., annealed for 1 h at 550 C and then water quenched, or material from the cooler region of the component. The Shippingport materials show modest decreases in fracture toughness and Charpy-impact properties and a small increase in tensile strength because of relatively low service temperatures and ferrite content of the steel. The procedure and correlations developed at Argonne National Laboratory for estimating mechanical properties of cast stainless steels predict accurate or slightly lower values for Charpy-impact energy, tensile flow stress, fracture toughness J-R curve, and J{sub IC} of the materials. The kinetics of thermal embrittlement and degree of embrittlement at saturation, i.e., the minimum impact energy achieved after long-term aging, were established from materials that were aged further in the laboratory. The results were consistent with the estimates. The correlations successfully predicted the mechanical properties of the Ringhals 2 reactor hot and crossover-leg elbows (CF-8M steel) after service of {approximately} 15 y and the KRB reactor pump cover plate (CF-8) after {approximately} 8 y of service.

  9. Mechanical properties of thermally aged cast stainless steels from shippingport reactor components.

    SciTech Connect

    Chopra, O. K.; Shack, W. J.; Energy Technology

    1995-06-07

    Thermal embrittlement of static-cast CF-8 stainless steel components from the decommissioned Shippingport reactor has been characterized. Cast stainless steel materials were obtained from four cold-leg check valves, three hot-leg main shutoff valves, and two pump volutes. The actual time-at-temperature for the materials was {approx}13 y at {approx}281 C (538 F) for the hot-leg components and {approx}264 C (507 F) for the cold-leg components. Baseline mechanical properties for as-cast material were determined from tests on either recovery-annealed material, i.e., annealed for 1 h at 550 C and then water quenched, or material from the cooler region of the component. The Shippingport materials show modest decreases in fracture toughness and Charpy-impact properties and a small increase in tensile strength because of relatively low service temperatures and ferrite content of the steel. The procedure and correlations developed at Argonne National Laboratory for estimating mechanical properties of cast stainless steels predict accurate or slightly lower values for Charpy-impact energy, tensile flow stress, fracture toughness J-R curve, and JIC of the materials. The kinetics of thermal embrittlement and degree of embrittlement at saturation, i.e., the minimum impact energy achieved after long-term aging, were established from materials that were aged further in the laboratory. The results were consistent with the estimates. The correlations successfully predicted the mechanical properties of the Ringhals 2 reactor hot- and crossover-leg elbows (CF-8M steel) after service of {approx}15 y and the KRB reactor pump cover plate (CF-8) after {approx}8 y of service.

  10. Thermal conductivity of commercially available 21-6-9 stainless steel

    SciTech Connect

    Yuecel, A.; Maddocks, J.R.

    1993-08-01

    Thermal conductivity values of 21-6-9 stainless steel over the temperature range of 5 K to 120 K are reported. Thermal conductivity integrals are measured using a steady-state heat flux method. The resulting data are fit with a polynomial and differentiated to obtain the conductivity. The derived conductivity is compared to published data for high-manganese stainless steels and to data for other stainless steels. A discussion of the methodology and its accuracy is included.

  11. Particle Impact Ignition Test Data on a Stainless Steel Hand Valve

    NASA Technical Reports Server (NTRS)

    Peralta, Stephen

    2010-01-01

    This slide presentation reviews the particle impact ignition test of a stainless steel hand valve. The impact of particles is a real fire hazard with stainless steel hand valves, however 100 mg of particulate can be tolerated. Since it is unlikely that 100 mg of stainless steel contaminant particles can be simultaneously released into this type of valve in the WSTF configuration, this is acceptable and within statistical confidence as demonstrated by testing.

  12. Tensile behavior of irradiated manganese-stabilized stainless steel

    SciTech Connect

    Klueh, R.L.

    1996-10-01

    Tensile tests were conducted on seven experimental, high-manganese austenitic stainless steels after irradiation up to 44 dpa in the FFTF. An Fe-20Mn-12Cr-0.25C base composition was used, to which various combinations of Ti, W, V, B, and P were added to improve strength. Nominal amounts added were 0.1% Ti, 1% W, 0.1% V, 0.005% B, and 0.03% P. Irradiation was carried out at 420, 520, and 600{degrees}C on the steels in the solution-annealed and 20% cold-worked conditions. Tensile tests were conducted at the irradiation temperature. Results were compared with type 316 SS. Neutron irradiation hardened all of the solution-annealed steels at 420, 520, and 600{degrees}C, as measured by the increase in yield stress and ultimate tensile strength. The steel to which all five elements were added to the base composition showed the least amount of hardening. It also showed a smaller loss of ductility (uniform and total elongation) than the other steels. The total and uniform elongations of this steel after irradiation at 420{degrees}C was over four times that of the other manganese-stabilized steels and 316 SS. There was much less difference in strength and ductility at the two higher irradiation temperatures, where there was considerably less hardening, and thus, less loss of ductility. In the cold-worked condition, hardening occured only after irradiation at 420{degrees}C, and there was much less difference in the properties of the steels after irradiation. At the 420{degrees}C irradiation temperature, most of the manganese-stabilized steels maintained more ductility than the 316 SS. After irradiation at 420{degrees}C, the temperature of maximum hardening, the steel to which all five of the elements were added had the best uniform elongation.

  13. High temperature properties of an austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Nikulin, I.; Kaibyshev, R.; Skorobogatykh, V.

    2010-07-01

    Tensile properties of the 18Cr-9Ni-W-Nb-V-N austenitic stainless steel were studied at strain rates ranging from 6.7×10-6 to 1.3×10-2 s-1 in the temperature interval 20-740°C. It was found that this steel exhibits jerky flow at temperatures ranging from 530 to 680°C and an initial strain rate of 1.3×10-3 s-1. This phenomenon was interpreted in terms of Portevin-Le Chatelier (PLC) effect occurring due to dynamic strain aging (DSA). PLC yields significant increase in high temperature strength of this steel due to extending of plateau on temperature dependence of yield strength (YS) and ultimate tensile strength (UTS) to higher temperatures. As a result, YS and UTS remain virtually unchanged with increasing temperature from 350 to 740°C. Role of additives of tungsten and vanadium in DSA and high temperatures strength of the austenitic stainless steel is discussed.

  14. Defect microstructures in neutron-irradiated copper and stainless steel

    SciTech Connect

    Zinkle, S.J.; Sindelar, R.L.

    1987-09-01

    The defect microstructures of copper and type 304L austenitic stainless steel have been examined following neutron irradiation under widely different conditions. Less than 0.2% of the defect clusters in steel irradiated at 120/sup 0/C with moderated fission neutrons were resolvable as stacking fault tetrahedra (SFT). The fraction of defect clusters identified as SFT in copper varied from approx.10% for a low-dose 14-MeV neutron irradiation at 25/sup 0/C to approx.50% for copper irradiated to 1.3 dpa in a moderated fission spectrum at 182/sup 0/C. The mean cluster size in copper was about 2.6 nm for both cases, despite the large differences in irradiation conditions. The mean defect cluster size in the irradiated steel was about 1.8 nm. The absence of SFT in stainless steel may be due to the generation of 35 appm He during the irradiation, which caused the vacancies to form helium-filled cavities instead of SFT. 20 refs.

  15. Superplastic Forming of Duplex Stainless Steel for Aerospace Part

    SciTech Connect

    Lee, Ho-Sung; Yoon, Jong-Hoon; Yoo, Joon-Tae; Yi, Young-Moo

    2011-08-22

    In this study, the high temperature forming behavior of duplex stainless steel has been characterized and the outer shell of a combustion chamber was fabricated with pressure difference of hot gas. It consists of two parts which are the outer skin made of stainless steel to sustain the internal pressure and the inner shell made of copper alloy for regenerative cooling channels. Two outer skins partitioned to half with respect to the symmetric axis was prepared by hot gas forming process with a maximum pressure of 7 MPa following to FEM analysis. For inner layer, copper alloy was machined for cooling channels and then placed in the gas pressure welding fixture. It is shown that the optimum condition of gas pressure welding is 7 MPa at 890 deg. C, for one hour. EDX analysis and scanning electron microscope micrograph confirm the atomic diffusion process is observed at the interface and copper atoms diffuse into steel, while iron and chrome atoms diffuse into copper. The result shows that the manufacturing method with superplastic forming and gas pressure welding of steel and copper alloy has been successful for near net shape manufacturing of scaled combustion chamber of launch vehicle.

  16. Hydrogen-related phase transformations in austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Narita, N.; Altstetter, C. J.; Birnbaum, H. K.

    1982-08-01

    The effect of hydrogen and stress (strain) on the stability of the austenite phase in stainless steels was investigated. Hydrogen was introduced by severe cathodic charging and by elevated temperature equilibration with high pressure H2 gas. Using X-ray diffraction and magnetic techniques, the behavior of two “stable” type AISI310 steels and an “unstable” type AISI304 steel was studied during charging and during the outgassing period following charging. Transformation from the fcc γ phase to an expanded fcc phase, γ*, and to the hcp ɛ phase occurred during cathodic charging. Reversion of the γ* and e phases to the original γ structure and formation of the bcc α structure were examined, and the kinetics of these processes was studied. The γ* phase was shown to be ferromagnetic with a subambient Curie temperature. The γ⇆ɛ phase transition was studied after hydrogen charging in high pressure gas, as was the formation of a during outgassing. These results are interpreted as effects of hydrogen and stress (strain) on the stability of the various phases. A proposed psuedo-binary phase diagram for the metal-hydrogen system was proposed to account for the formation of the γ* phase. The relation of these phase changes to hydrogen embrittlement and stress corrosion cracking of stainless steel is discussed.

  17. Correlation Between Shear Punch and Tensile Strength for Low-Carbon Steel and Stainless Steel Sheets

    NASA Astrophysics Data System (ADS)

    Mahmudi, R.; Sadeghi, M.

    2013-02-01

    The deformation behavior of AISI 1015 low-carbon steel, and AISI 304 stainless steel sheets was investigated by uniaxial tension and the shear punch test (SPT). Both materials were cold rolled to an 80% thickness reduction and subsequently annealed in the temperature range 25-850 °C to produce a wide range of yield and ultimate strength levels. The correlations between shear punch and tensile yield and ultimate stresses were established empirically. Different linear relationships having different slopes and intercepts were found for the low-carbon and stainless steel sheets, and the possible parameters affecting the correlation were discussed. It was shown that, within limits, yield and tensile strength of thin steel sheets can be predicted from the shear data obtained by the easy-to-perform SPT.

  18. Electrochemical and passivation behavior investigation of ferritic stainless steel in simulated concrete pore media.

    PubMed

    Luo, Hong; Su, Huaizhi; Dong, Chaofang; Xiao, Kui; Li, Xiaogang

    2015-12-01

    The applications of stainless steel are one of the most reliable solutions in concrete structures to reduce chloride-induced corrosion problems and increase the structures service life, however, due to high prices of nickel, especially in many civil engineering projects, the austenitic stainless steel is replaced by the ferritic stainless steels. Compared with austenite stainless steel, the ferritic stainless steel is known to be extremely resistant of stress corrosion cracking and other properties. The good corrosion resistance of the stainless steel is due to the formation of passive film. While, there is little literature about the electrochemical and passive behavior of ferritic stainless steel in the concrete environments. So, here, we present the several corrosion testing methods, such as the potentiodynamic measurements, EIS and Mott-Schottky approach, and the surface analysis methods like XPS and AES to display the passivation behavior of 430 ferritic stainless steel in alkaline solution with the presence of chloride ions. These research results illustrated a simple and facile approach for studying the electrochemical and passivation behavior of stainless steel in the concrete pore environments. PMID:26501086

  19. Electrochemical and passivation behavior investigation of ferritic stainless steel in simulated concrete pore media

    PubMed Central

    Luo, Hong; Su, Huaizhi; Dong, Chaofang; Xiao, Kui; Li, Xiaogang

    2015-01-01

    The applications of stainless steel are one of the most reliable solutions in concrete structures to reduce chloride-induced corrosion problems and increase the structures service life, however, due to high prices of nickel, especially in many civil engineering projects, the austenitic stainless steel is replaced by the ferritic stainless steels. Compared with austenite stainless steel, the ferritic stainless steel is known to be extremely resistant of stress corrosion cracking and other properties. The good corrosion resistance of the stainless steel is due to the formation of passive film. While, there is little literature about the electrochemical and passive behavior of ferritic stainless steel in the concrete environments. So, here, we present the several corrosion testing methods, such as the potentiodynamic measurements, EIS and Mott–Schottky approach, and the surface analysis methods like XPS and AES to display the passivation behavior of 430 ferritic stainless steel in alkaline solution with the presence of chloride ions. These research results illustrated a simple and facile approach for studying the electrochemical and passivation behavior of stainless steel in the concrete pore environments. PMID:26501086

  20. Improved corrosion resistance of 316L stainless steel by nanocrystalline and electrochemical nitridation in artificial saliva solution

    NASA Astrophysics Data System (ADS)

    Lv, Jinlong; Liang, Tongxiang

    2015-12-01

    The fluoride ion in artificial saliva significantly changed semiconductor characteristic of the passive film formed on the surface of 316L stainless steels. The electrochemical results showed that nanocrystalline α‧-martensite improved corrosion resistance of the stainless steel in a typical artificial saliva compared with coarse grained stainless steel. Moreover, comparing with nitrided coarse grained stainless steel, corrosion resistance of the nitrided nanocrystalline stainless steel was also improved significantly, even in artificial saliva solution containing fluoride ion. The present study showed that the cryogenic cold rolling and electrochemical nitridation improved corrosion resistance of 316L stainless steel for the dental application.

  1. The interaction between nitride uranium and stainless steel

    NASA Astrophysics Data System (ADS)

    Shornikov, D. P.; Nikitin, S. N.; Tarasov, B. A.; Baranov, V. G.; Yurlova, M. S.

    2016-04-01

    Uranium nitride is most popular nuclear fuel for Fast Breeder Reactor New Generation. In-pile experiments at reactor BOR-60 was shown an interaction between nitride fuel and stainless steel in the range of 8-11% burn up (HA). In order to investigate this interaction has been done diffusion tests of 200 h and has been shown that the reaction occurs in the temperature range 1000-1100 ° C. UN interacted with steel in case of high pollution oxygen (1000-2000 ppm). Also has been shown to increase interaction UN with EP-823 steel in the presence of cesium. In this case the interaction layer had a thickness about 2-3 μm. Has been shown minimal interaction with new ODS steel EP-450. The interaction layer had a thickness less then 2 μm. Did not reveal the influence of tellurium and iodine increased interaction. It was show compatibility at 1000 °C between UN and EP-450 ODS steel, chrome steel, alloying aluminium and silicium.

  2. Double-Sided Single-Pass Submerged Arc Welding for 2205 Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Luo, Jian; Yuan, Yi; Wang, Xiaoming; Yao, Zongxiang

    2013-09-01

    The duplex stainless steel (DSS), which combines the characteristics of ferritic steel and austenitic steel, is used widely. The submerged arc welding (SAW) method is usually applied to join thick plates of DSS. However, an effective welding procedure is needed in order to obtain ideal DSS welds with an appropriate proportion of ferrite (δ) and austenite (γ) in the weld zone, particularly in the melted zone and heat-affected zone. This study evaluated the effectiveness of a high efficiency double-sided single-pass (DSSP) SAW joining method for thick DSS plates. The effectiveness of the converse welding procedure, characterizations of weld zone, and mechanical properties of welded joint are analyzed. The results show an increasing appearance and continuous distribution feature of the σ phase in the fusion zone of the leading welded seam. The converse welding procedure promotes the σ phase to precipitate in the fusion zone of leading welded side. The microhardness appears to significantly increase in the center of leading welded side. Ductile fracture mode is observed in the weld zone. A mixture fracture feature appears with a shear lip and tears in the fusion zone near the fusion line. The ductility, plasticity, and microhardness of the joints have a significant relationship with σ phase and heat treatment effect influenced by the converse welding step. An available heat input controlling technology of the DSSP formation method is discussed for SAW of thick DSS plates.

  3. Semen quality and sex hormones among mild steel and stainless steel welders: a cross sectional study.

    PubMed Central

    Bonde, J P

    1990-01-01

    Welding may be detrimental to the male reproductive system. To test this hypothesis, semen quality was examined in 35 stainless steel welders, 46 mild steel welders, and 54 non-welding metal workers and electricians. These figures represent a participation rate of 37.1% in welders and 36.7% in non-welding subjects. The mean exposure to welding fume particulates was 1.3 mg/m3 (SD 0.8) in stainless steel welders using tungsten inert gas, 3.2 mg/m3 (SD 1.0) in low exposed mild steel welders using manual metal arc or metal active gas (n = 31), and 4.7 mg/m3 (SD 2.1) in high exposed mild steel welders (n = 15). The semen quality of each participant was defined in terms of the mean values of the particular semen parameters in three semen samples delivered at monthly intervals in a period with occupational exposure in a steady state. The sperm concentration was not reduced in either mild steel or stainless steel welders. The sperm count per ejaculate, the proportion of normal sperm forms, the degree of sperm motility, and the linear penetration rate of the sperm were significantly decreased and the sperm concentration of follicle stimulating hormone (FSH) was non-significantly increased in mild steel welders. A dose response relation between exposure to welding fumes and these semen parameters (sperm count excepted) was found. Semen quality decreased and FSH concentrations increased with increasing exposure. Significant deteriorations in some semen parameters were also observed in stainless steel welders. An analysis of information from questionnaires obtained from the whole population including subjects who declined to participate indicated an underestimation of effects due to selection bias. Potential confounding was treated by restriction and statistical analysis. The results support the hypothesis that mild steel welding and to a lesser extent stainless steel welding with tungsten inert gas is associated with reduced semen quality at exposure in the range of the

  4. High-pressure stainless steel active membrane microvalves

    NASA Astrophysics Data System (ADS)

    Sharma, G.; Svensson, S.; Ogden, S.; Klintberg, L.; Hjort, K.

    2011-07-01

    In this work, high-pressure membrane microvalves have been designed, manufactured and evaluated. The valves were able to withstand back-pressures of 200 bar with a response time of less than 0.6 s. These stainless steel valves, manufactured with back-end batch production, utilize the large volume expansion coupled to the solid-liquid phase transition in paraffin wax. When membrane materials were evaluated, parylene coated stainless steel was found to be the best choice as compared to polydimethylsiloxane and polyimide. Also, the influence of the orifice placement and diameter is included in this work. If the orifice is placed too close to the rim of the membrane, the valve can stay sealed even after turning the power off, and the valve will not open until the pressure in the system is released. The developed steel valves, evaluated for both water and air, provide excellent properties in terms of mechanical stability, ease of fabrication, and low cost. Possible applications include sampling at high pressures, chemical microreactors, high performance liquid chromatography, pneumatics, and hydraulics.

  5. Cold Spray Repair of Martensitic Stainless Steel Components

    NASA Astrophysics Data System (ADS)

    Faccoli, M.; Cornacchia, G.; Maestrini, D.; Marconi, G. P.; Roberti, R.

    2014-12-01

    The possibility of using cold spray as repair technique of martensitic stainless steel components was evaluated through laboratory investigations. An austenitic stainless steel feedstock powder was chosen, instead of soft metals powders like nickel, copper, or aluminum, used for repairing components made in light alloy or cast iron. The present study directly compares the microstructure, the residual stresses, and the micro-hardness of repairs obtained by cold spray and by TIG welding, that is commonly used as repair technique in large steel components. XRD and optical metallographic analysis of the repairs showed that cold spray offers some advantages, inducing compressive residual stresses in the repair and avoiding alterations of the interface between repair and base material. For these reasons, a heat treatment after the cold spray repair is not required to restore the base material properties, whereas a post-weld heat treatment is needed after the welding repair. Cold spray repair also exhibits a higher micro-hardness than the welding repair. In addition, the cavitation erosion resistance of a cold spray coating was investigated through ultrasonic cavitation tests, and the samples worn surfaces were observed by scanning electron microscopy.

  6. Sensitization of Laser-beam Welded Martensitic Stainless Steels

    NASA Astrophysics Data System (ADS)

    Dahmen, Martin; Rajendran, Kousika Dhasanur; Lindner, Stefan

    Ferritic and martensitic stainless steels are an attractive alternative in vehicle production due to their inherent corrosion resistance. By the opportunity of press hardening, their strength can be increased to up to 2000 MPa, making them competitors for unalloyed ultra-high strength steels. Welding, nevertheless, requires special care, especially when it comes to joining of high strength heat treated materials. With an adopted in-line heat treatment of the welds in as-rolled as well as press hardened condition, materials with sufficient fatigue strength and acceptable structural behavior can be produced. Because of microstructural transformations in the base material such as grain coarsening and forced carbide precipitation, the corrosion resistance of the weld zone may be locally impaired. Typically the material in the heat-affected zone becomes sensitive to intergranular cracking in the form of knife-edge corrosion besides the fusion line. The current study comprises of two text scenarios. By an alternating climate test, general response in a corroding environment is screened. In order to understand the corrosion mechanisms and to localize the sensitive zones, sensitisation tests were undertaken. Furthermore, the applicability of a standard test according to ASTM 763-83 was examined. It was found that the alternative climate test does not reveal any corrosion effects. Testing by the oxalic acid test revealed clearly the effect of welding, weld heat treatment and state of thermal processing. Also application of the standard which originally suited for testing ferritic stainless steels could have been justified.

  7. A review on nickel-free nitrogen containing austenitic stainless steels for biomedical applications.

    PubMed

    Talha, Mohd; Behera, C K; Sinha, O P

    2013-10-01

    The field of biomaterials has become a vital area, as these materials can enhance the quality and longevity of human life. Metallic materials are often used as biomaterials to replace structural components of the human body. Stainless steels, cobalt-chromium alloys, commercially pure titanium and its alloys are typical metallic biomaterials that are being used for implant devices. Stainless steels have been widely used as biomaterials because of their very low cost as compared to other metallic materials, good mechanical and corrosion resistant properties and adequate biocompatibility. However, the adverse effects of nickel ions being released into the human body have promoted the development of "nickel-free nitrogen containing austenitic stainless steels" for medical applications. Nitrogen not only replaces nickel for austenitic structure stability but also much improves steel properties. Here we review the harmful effects associated with nickel and emphatically the advantages of nitrogen in stainless steel, as well as the development of nickel-free nitrogen containing stainless steels for medical applications. By combining the benefits of stable austenitic structure, high strength, better corrosion and wear resistance and superior biocompatibility in comparison to the currently used austenitic stainless steel (e.g. 316L), the newly developed nickel-free high nitrogen austenitic stainless steel is a reliable substitute for the conventionally used medical stainless steels. PMID:23910251

  8. DCEMS Study of Thin Oxide Layers and Interface of Stainless Steel Films Deposited by Sputtering Austenitic AISI304

    NASA Astrophysics Data System (ADS)

    Nomura, K.; Takahashi, K.; Takeda, M.; Shimizu, K.; Habasaki, H.; Kuzmann, E.

    2004-12-01

    Thin stainless steel films were deposited on surface oxidized Si plate using austenitic AISI304 stainless steel as target with a RF magnetron Ar sputtering method. The deposited films and the oxidized films with about 15 nm in thickness were characterized by depth selective conversion electron Mössbauer spectroscopy (DCEMS) using a 2π gas proportional counter. The as-deposited film consisted of ferromagnetic phase. The average hyperfine magnetic fields increased from 25 to 28 T by heating. A relative large amount of iron oxide (Fe2O3) was produced on the top surface layer upon heating at 400°C. After heating at 500°C the relative amount of iron oxide decreased and chromium oxide layers grew in the interface between the iron oxide and substrate layers. The ferromagnetic phase in the deposited stainless steel film was partially converted into austenitic phase at 500°C and largely at 600°C. DCEMS is effective for non-destructive characterization of both surface and interface layers of thin stainless steel films with several 10 nm thickness.

  9. Joining dissimilar stainless steels for pressure vessel components

    NASA Astrophysics Data System (ADS)

    Sun, Zheng; Han, Huai-Yue

    1994-03-01

    A series of studies was carried out to examine the weldability and properties of dissimilar steel joints between martensitic and austenitic stainless steels - F6NM (OCr13Ni4Mo) and AISI 347, respectively. Such joints are important parts in, e.g. the primary circuit of a pressurized water reactor (PWR). This kind of joint requires both good mechanical properties, corrosion resistance and a stable magnetic permeability besides good weldability. The weldability tests included weld thermal simulation of the martensitic steel for investigating the influence of weld thermal cycles and post-weld heat treatment (PWHT) on the mechanical properties of the heat-affected zone (HAZ); implant testing for examining the tendency for cold cracking of martensitic steel; rigid restraint testing for determining hot crack susceptibility of the multi-pass dissimilar steel joints. The joints were subjected to various mechanical tests including a tensile test, bending test and impact test at various temperatures, as well as slow strain-rate test for examining the stress corrosion cracking tendency in the simulated environment of a primary circuit of a PWR. The results of various tests indicated that the quality of the tube/tube joints is satisfactory for meeting all the design requirements.

  10. Biomonitoring of genotoxic exposure among stainless steel welders.

    PubMed

    Knudsen, L E; Boisen, T; Christensen, J M; Jelnes, J E; Jensen, G E; Jensen, J C; Lundgren, K; Lundsteen, C; Pedersen, B; Wassermann, K

    1992-05-16

    A biosurvey in the Danish metal industry measured the genotoxic exposure from stainless steel welding. The study comprised measurements of chromosomal aberrations (CA), sister-chromatid exchanges (SCE), unscheduled DNA synthesis (UDS) in peripheral lymphocytes and serum immunoglobulin G. Environmental monitoring of welding fumes and selected metal oxides, biomonitoring of chromium and nickel in serum and urine and mutagenic activity in urine, and evaluation of semen quality were also done. Manual metal arc (MMA) welding and tungsten inert gas (TIG) welding were the dominant welding processes. A higher frequency of chromosomal aberrations, classified as translocations, double minutes, exchanges and rings, was observed in stainless steel welders than in non-welders. SCE was lower in welders working with both MMA and TIG welding than in reference persons. N-Acetoxy-N-acetylaminofluorene (NA-AAF)-induced UDS was lower in 23 never-smoking welders than in 19 unexposed never-smokers. Smoking was a confounding factor resulting in significantly higher CA, SCE, NA-AAF binding to DNA and mutagenic activity in urine. Age was also a confounder: CA, SCE, NA-AAF binding to DNA and UDS increased significantly with age. No significant correlation between SCE and CA or between CA and UDS was found. UDS decreased significantly with increasing lymphocyte count and a higher lymphocyte count was seen in MMA welders than in reference persons and in smokers than in non-smokers. Differences in the composition among lymphocytes in exposed persons compared with non-exposed are suggested. MMA welding gave the highest exposure to chromium, an increased number of chromosomal aberrations and a decrease in SCE when compared with TIG welding. Consequently improvements in the occupational practice of stainless steel welding with MMA is recommended. PMID:1375338

  11. Aging and Embrittlement of High Fluence Stainless Steels

    SciTech Connect

    Was, gary; Jiao, Zhijie; der ven, Anton Van; Bruemmer, Stephen; Edwards, Dan

    2012-12-31

    Irradiation of austenitic stainless steels results in the formation of dislocation loops, stacking fault tetrahedral, Ni-Si clusters and radiation-induced segregation (RIS). Of these features, it is the formation of precipitates which is most likely to impact the mechanical integrity at high dose. Unlike dislocation loops and RIS, precipitates exhibit an incubation period that can extend from 10 to 46 dpa, above which the cluster composition changes and a separate phase, (G-phase) forms. Both neutron and heavy ion irradiation showed that these clusters develop slowly and continue to evolve beyond 100 dpa. Overall, this work shows that the irradiated microstructure features produced by heavy ion irradiation are remarkably comparable in nature to those produced by neutron irradiation at much lower dose rates. The use of a temperature shift to account for the higher damage rate in heavy ion irradiation results in a fairly good match in the dislocation loop microstructure and the precipitate microstructure in austenitic stainless steels. Both irradiations also show segregation of the same elements and in the same directions, but to achieve comparable magnitudes, heavy ion irradiation must be conducted at a much higher temperature than that which produces a match with loops and precipitates. First-principles modeling has confirmed that the formation of Ni-Si precipitates under irradiation is likely caused by supersaturation of solute to defect sinks caused by highly correlated diffusion of Ni and Si. Thus, the formation and evolution of Ni-Si precipitates at high dose in austenitic stainless steels containing Si is inevitable.

  12. Systems design of high-performance stainless steels

    NASA Astrophysics Data System (ADS)

    Campbell, Carelyn Elizabeth

    A systems approach has been applied to the design of high performance stainless steels. Quantitative property objectives were addressed integrating processing/structure/property relations with mechanistic models. Martensitic transformation behavior was described using the Olson-Cohen model for heterogeneous nucleation and the Ghosh-Olson solid-solution strengthening model for interfacial mobility, and incorporating an improved description of Fe-Co-Cr thermodynamic interaction. Coherent Msb2C precipitation in a BCC matrix was described, taking into account initial paraequilibrium with cementite. Using available SANS data, a composition dependent strain energy was calibrated and a composition independent interfacial energy was evaluated to predict the critical particle size versus the fraction of the reaction completed as input to strengthening theory. Multicomponent Pourbaix diagrams provided an effective tool for evaluating oxide stability; constrained equilibrium calculations correlated oxide stability to Cr enrichment in the oxide film to allow more efficient use of alloy Cr content. Multicomponent solidification simulations provided composition constraints to improve castability. Using the Thermo-Calc and DICTRA software packages, the models were integrated to design a carburizing, secondary-hardening martensitic stainless steel. Initial characterization of the prototype showed good agreement with the design models and achievement of the desired property objectives. Prototype evaluation confirmed the predicted martensitic transformation temperature and the desired carburizing response, achieving a case hardness of Rsb{c} 64 in the secondary-hardened condition without case primary carbides. Decarburization experiments suggest that the design core toughness objective (Ksb{IC} = 65 MPasurdm) can be achieved by reducing the core carbon level to 0.05 weight percent. To achieve the core toughness objective at high core strength levels requires further analysis of an

  13. Thermal Aging Phenomena in Cast Duplex Stainless Steels

    DOE PAGESBeta

    Byun, T. S.; Yang, Y.; Overman, N. R.; Busby, J. T.

    2015-11-12

    We used cast stainless steels (CASSs)for the large components of light water reactor (LWR) power plants such as primary coolant piping and pump casing. The thermal embrittlement of CASS components is one of the most serious concerns related to the extended-term operation of nuclear power plants. Many past researches have concluded that the formation of Cr-rich alpha-phase by Spinodal decomposition of delta-ferrite phase is the primary mechanism for the thermal embrittlement. Cracking mechanism in the thermally-embrittled duplex stainless steels consists of the formation of cleavage at ferrite and its propagation via separation of ferrite-austenite interphase. This article intends to providemore » an introductory overview on the thermal aging phenomena in LWR-relevant conditions. Firstly, the thermal aging effect on toughness is discussed in terms of the cause of embrittlement and influential parameters. Moreover, an approximate analysis of thermal reaction using Arrhenius equation was carried out to scope the aging temperatures for the accelerated aging experiments to simulate the 60 and 80 years of services. Further, an equilibrium precipitation calculation was performed for model CASS alloys using the CALPHAD program, and the results are used to describe the precipitation behaviors in duplex stainless steels. Our results are also to be used to guide an on-going research aiming to provide knowledge-based conclusive prediction for the integrity of the CASS components of LWR power plants during the service life extended up to and beyond 60 years.« less

  14. Influence of fretting on flexural fatigue of 304 stainless steel and mild steel

    NASA Technical Reports Server (NTRS)

    Bill, R. C.; Rohn, D. A.

    1978-01-01

    Fretting fatigue experiments conducted on 304 stainless steel using a flexural fatigue test arrangement with bolted on fretting pads demonstrated that fatigue life is reduced by at least a factor of 10 in the 265 to 334 MPa (38,500 - to 48,500 psi) nominal flexural fatigue stress range. In addition, experiments in which the fretting pads were removed after selected numbers of cycles, followed by continued flexural fatigue without fretting show that continued fretting beyond 50,000 cycles does not significantly further reduce fatigue life of 304 stainless steel at 317 MPa (46,000 psi). Microscopic examination of the fretted contact areas revealed fracture initiation sites as well as numerous cracks that did not propagate to failure. Flexural fretting fatigue experiments performed on mild steel showed an insensitivity of fatigue life to the incidence of fretting under flexural stress conditions of from 162 to 217 MPa (23,500 to 31,500 psi).

  15. Cytotoxicity study of plasma-sprayed hydroxyapatite coating on high nitrogen austenitic stainless steels.

    PubMed

    Ossa, C P O; Rogero, S O; Tschiptschin, A P

    2006-11-01

    Stainless steel has been frequently used for temporary implants but its use as permanent implants is restricted due to its low pitting corrosion resistance. Nitrogen additions to these steels improve both mechanical properties and corrosion resistance, particularly the pitting and crevice corrosion resistance. Many reports concerning allergic reactions caused by nickel led to the development of nickel free stainless steel; it has excellent mechanical properties and very high corrosion resistance. On the other hand, stainless steels are biologically tolerated and no chemical bonds are formed between the steel and the bone tissue. Hydroxyapatite coatings deposited on stainless steels improve osseointegration, due their capacity to form chemical bonds (bioactive fixation) with the bone tissue. In this work hydroxyapatite coatings were plasma-sprayed on three austenitic stainless steels: ASTM-F138, ASTM-F1586 and the nickel-free Böhler-P558. The coatings were analyzed by SEM and XDR. The cytotoxicity of the coatings/steels was studied using the neutral red uptake method by quantitative evaluation of cell viability. The three uncoated stainless steels and the hydroxyapatite coated Böhler-P558 did not have any toxic effect on the cell culture. The hydroxyapatite coated ASTM-F138 and ASTM-F1586 stainless steels presented cytotoxicity indexes (IC50%) lower than 50% and high nickel contents in the extracts. PMID:17122924

  16. Shrinkage Prediction for the Investment Casting of Stainless Steels

    SciTech Connect

    Sabau, Adrian S

    2007-01-01

    In this study, the alloy shrinkage factors were obtained for the investment casting of 17-4PH stainless steel parts. For the investment casting process, unfilled wax and fused silica with a zircon prime coat were used for patterns and shell molds, respectively. Dimensions of the die tooling, wax pattern, and casting were measured using a Coordinate Measurement Machine in order to obtain the actual tooling allowances. The alloy dimensions were obtained from numerical simulation results of solidification, heat transfer, and deformation phenomena. The numerical simulation results for the shrinkage factors were compared with experimental results.

  17. Use of duplex stainless steel castings in control valves

    SciTech Connect

    Gossett, J.L.

    1996-07-01

    Duplex stainless steels have enjoyed rapidly increasing popularity in recent years. For numerous reasons the availability of these alloys in the cast form has lagged behind the availability of the wrought form. Commercial demand for control valves in these alloys has driven development of needed information to move into production. A systematic approach was used to develop specifications, suppliers and weld procedures. Corrosion, stress corrosion cracking (SCC), sulfide stress cracking (SSC) and hardness results are also presented for several alloys including; CD3MN (UNS J92205), CD4MCu (UNS J93370) and CD7MCuN (cast UNS S32550).

  18. Oxidation resistant high creep strength austenitic stainless steel

    DOEpatents

    Brady, Michael P.; Pint, Bruce A.; Liu, Chain-Tsuan; Maziasz, Philip J.; Yamamoto, Yukinori; Lu, Zhao P.

    2010-06-29

    An austenitic stainless steel displaying high temperature oxidation and creep resistance has a composition that includes in weight percent 15 to 21 Ni, 10 to 15 Cr, 2 to 3.5 Al, 0.1 to 1 Nb, and 0.05 to 0.15 C, and that is free of or has very low levels of N, Ti and V. The alloy forms an external continuous alumina protective scale to provide a high oxidation resistance at temperatures of 700 to 800.degree. C. and forms NbC nanocarbides and a stable essentially single phase fcc austenitic matrix microstructure to give high strength and high creep resistance at these temperatures.

  19. Portable probe to measure sensitization of stainless steel

    DOEpatents

    Park, Jang Y.

    1979-01-01

    An electrochemical cell for making field measurements of metals such as stainless steel comprises a cylinder containing a reservoir of an electrolyte, a reference electrode, a capillary tube connecting the electrolyte to the surface of the metal to be measured and another electrode in electrical contact with the electrolyte. External connections from the reference electrode, the other electrode, and the sample to a measuring device provide means for maintaining the potential of the electrolyte while sweeping the potential difference between the electrolyte and the metal. Such a sweep enables the determination of a current-voltage characteristic that is a measure of sensitization in the metal.

  20. Apparatus and process for ultrasonic seam welding stainless steel foils

    DOEpatents

    Leigh, Richard W.

    1992-01-01

    An ultrasonic seam welding apparatus having a head which is rotated to form contact, preferably rolling contact, between a metallurgically inert coated surface of the head and an outside foil of a plurality of layered foils or work materials. The head is vibrated at an ultrasonic frequency, preferably along a longitudinal axis of the head. The head is constructed to transmit vibration through a contacting surface of the head into each of the layered foils. The contacting surface of the head is preferably coated with aluminum oxide to prevent the head from becoming welded to layered stainless steel foils.

  1. Surface characterization of adsorbed asphaltene on a stainless steel surface

    NASA Astrophysics Data System (ADS)

    Abdallah, W. A.; Taylor, S. D.

    2007-05-01

    X-ray photoelectron spectroscopy was used to characterize a single layer of adsorbed asphaltene on a metallic surface. The deposits were created by immersing a stainless steel disc into a dilute asphaltene solution with either toluene or dichloromethane as the solvent, although the toluene solution allowed for better control of the adsorbed asphaltene layer and less atmospheric oxygen contamination. The analyses for C 1s, S 2p3/2, N 1s and O 1s photoemission peaks indicated that different functional groups are present in the asphaltene layer including carboxylic, pyrrolic, pyridininc, thiophenic and sulfite, with slight differences in their binding energies.

  2. General and Localized Corrosion of Borated Stainless Steels

    SciTech Connect

    T.E. Lister; Ronald E. Mizia; A.W. Erickson; T.L. Trowbridge; B. S. Matteson

    2008-03-01

    The Transportation, Aging and Disposal (TAD) canister-based system is being proposed to transport and store spent nuclear fuel at the Monitored Geologic Repository (MGR) located at Yucca Mountain, Nevada. The preliminary design of this system identifies borated stainless steel as the neutron absorber material that will be used to fabricate fuel basket inserts for nuclear criticality control. This paper discusses corrosion test results for verifying the performance of this material manufactured to the requirements of ASTM A887, Grade A, under the expected repository conditions.

  3. Modeling of Linear Gas Tungsten Arc Welding of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Maran, P.; Sornakumar, T.; Sundararajan, T.

    2008-08-01

    A heat and fluid flow model has been developed to solve the gas tungsten arc (GTA) linear welding problem for austenitic stainless steel. The moving heat source problem associated with the electrode traverse has been simplified into an equivalent two-dimensional (2-D) transient problem. The torch residence time has been calculated from the arc diameter and torch speed. The mathematical formulation considers buoyancy, electromagnetic induction, and surface tension forces. The governing equations have been solved by the finite volume method. The temperature and velocity fields have been determined. The theoretical predictions for weld bead geometry are in good agreement with experimental measurements.

  4. Hardening of aged duplex stainless steels by spinodal decomposition.

    PubMed

    Danoix, F; Auger, P; Blavette, D

    2004-06-01

    Mechanical properties, such as hardness and impact toughness, of ferrite-containing stainless steels are greatly affected by long-term aging at intermediate temperatures. It is known that the alpha-alpha' spinodal decomposition occurring in the iron-chromium-based ferrite is responsible for this aging susceptibility. This decomposition can be characterized unambiguously by atom probe analysis, allowing comparison both with the existing theories of spinodal decomposition and the evolution of some mechanical properties. It is then possible to predict the evolution of hardness of industrial components during service, based on the detailed knowledge of the involved aging process. PMID:15233853

  5. Low cycle fatigue behavior of aluminum/stainless steel composites

    NASA Technical Reports Server (NTRS)

    Bhagat, R. B.

    1983-01-01

    Composites consisting of an aluminum matrix reinforced with various volume fractions of stainless steel wire were fabricated by hot die pressing under various conditions of temperature, time, and pressure. The composites were tested in plane bending to complete fracture under cycle loading, and the results were analyzed on a computer to obtain a statistically valid mathematical relationship between the low-cycle fatigue life and the fiber volume fraction of the composite. The fractured surfaces of the composites were examined by scanning electron microscopy to identify the characteristic features of fatigue damage. Fatigue damage mechanisms are proposed and discussed.

  6. Fiber laser micro-cutting of stainless steel sheets

    NASA Astrophysics Data System (ADS)

    Baumeister, M.; Dickmann, K.; Hoult, T.

    2006-11-01

    The authors report on laser micro-cutting results for stainless steel foils with the aid of a 100 W fiber laser. This novel laser source combines a high output power in relation to conventional laser sources for micro-processing applications with an excellent beam quality (M2=1.1). Different material thicknesses were evaluated (100 μm to 300 μm). Processing was carried out with cw operation of the laser source, and with nitrogen and oxygen as assisting gases. Besides the high processing rate of oxygen assisted cutting, a better cutting performance in terms of a lower kerf width was obtained.

  7. Equation of state and electrical conductivity of stainless steel.

    SciTech Connect

    Desjarlais, Michael Paul; Mattsson, Thomas Kjell Rene

    2004-11-01

    Warm dense matter is the region in phase space of density and temperature where the thermal, Fermi, and Coulomb energies are approximately equal. The lack of a dominating scale and physical behavior makes it challenging to model the physics to high fidelity. For Sandia, a fundamental understanding of the region is of importance because of the needs of our experimental HEDP programs for high fidelity descriptive and predictive modeling. We show that multi-scale simulations of macroscopic physical phenomena now have predictive capability also for difficult but ubiquitous materials such as stainless steel, a transition metal alloy.

  8. Carbon, nitrogen, and oxygen ion implantation of stainless steel

    SciTech Connect

    Rej, D.J.; Gavrilov, N.V.; Emlin, D.

    1995-12-31

    Ion implantation experiments of C, N, and O into stainless steel have been performed, with beam-line and plasma source ion implantation methods. Acceleration voltages were varied between 27 and 50 kV, with pulsed ion current densities between 1 and 10 mA/cm{sup 2}. Implanted doses ranged from 0.5 to 3 {times} 10{sup 18}cm{sup -2}, while workpiece temperatures were maintained between 25 and 800 C. Implant concentration profiles, microstructure, and surface mechanical properties of the implanted materials are reported.

  9. Laser-induced color marking of stainless steel

    NASA Astrophysics Data System (ADS)

    Antonczak, Arkadiusz J.; Nowak, Maciej; Koziol, Pawel; Kaczmarek, Pawel R.; Waz, Adam T.; Abramski, Krzysztof M.

    2013-01-01

    This paper presents the analysis of the impact of selected process parameters on the resulting laser color marking. The study was conducted for AISI 304 multipurpose stainless steel using a commercially available industrial fiber laser. It was determined how various process parameters, such as laser power, scanning speed of the laser beam, temperature of the material, location of the sample relative to the focal plane, affect the repeatability of the colors obtained. For objective assessment of color changes, an optical spectrometer and the CIE color difference parameter ΔEab * were used.

  10. Laser Welding of Large Scale Stainless Steel Aircraft Structures

    NASA Astrophysics Data System (ADS)

    Reitemeyer, D.; Schultz, V.; Syassen, F.; Seefeld, T.; Vollertsen, F.

    In this paper a welding process for large scale stainless steel structures is presented. The process was developed according to the requirements of an aircraft application. Therefore, stringers are welded on a skin sheet in a t-joint configuration. The 0.6 mm thickness parts are welded with a thin disc laser, seam length up to 1920 mm are demonstrated. The welding process causes angular distortions of the skin sheet which are compensated by a subsequent laser straightening process. Based on a model straightening process parameters matching the induced welding distortion are predicted. The process combination is successfully applied to stringer stiffened specimens.

  11. Microstructures of laser deposited 304L austenitic stainless steel

    SciTech Connect

    BROOKS,JOHN A.; HEADLEY,THOMAS J.; ROBINO,CHARLES V.

    2000-05-22

    Laser deposits fabricated from two different compositions of 304L stainless steel powder were characterized to determine the nature of the solidification and solid state transformations. One of the goals of this work was to determine to what extent novel microstructure consisting of single-phase austenite could be achieved with the thermal conditions of the LENS [Laser Engineered Net Shape] process. Although ferrite-free deposits were not obtained, structures with very low ferrite content were achieved. It appeared that, with slight changes in alloy composition, this goal could be met via two different solidification and transformation mechanisms.

  12. Aluminum nanocomposites having wear resistance better than stainless steel

    SciTech Connect

    An, Linan; Qu, Jun; Luo, Jinsong; Fan, Yi; Zhang, Ligong; Liu, Jinling; Xu, Chengying; Blau, Peter Julian

    2011-01-01

    Tribological behavior of alumina-particle-reinforced aluminum composites made by powder metallurgy process has been investigated. The nanocomposite containing 15 vol% of Al2O3 nanoparticles exhibits excellent wear resistance by showing significantly low wear rate and abrasive wear mode. The wear rate of the nanocomposite is even lower than stainless steel. We have also demonstrated that such excellent wear resistance only occurred in the composite reinforced with the high volume fraction of nanosized reinforcing particles. The results were discussed in terms of the microstructure of the nanocomposite.

  13. Iron contamination causes stress corrosion cracking in stainless steels

    SciTech Connect

    Khatak, H.S.; Bharasi, N.S.; Gnanamoorthy, J.B. . Metallurgy Div.)

    1994-06-01

    Iron-contaminated U-bend samples of types 316 and 304 stainless steels (SS) were exposed to a sodium chloride solution in the laboratory at room temperature. Two of the four samples of 304 SS and one of the four samples of 316 SS showed cracking. The cracks initiated in the iron-contaminated regions. Based on the results of these tests, the failure of many components in industries can be explained and the importance of carrying out pickling and passivation immediately after fabrication to remove possible iron contamination is highlighted.

  14. High Strength Stainless Steel Properties that Affect Resistance Welding

    SciTech Connect

    Kanne, W.R.

    2001-08-01

    This report discusses results of a study on selected high strength stainless steel alloy properties that affect resistance welding. The austenitic alloys A-286, JBK-75 (Modified A-286), 21-6-9, 22-13-5, 316 and 304L were investigated and compared. The former two are age hardenable, and the latter four obtain their strength through work hardening. Properties investigated include corrosion and its relationship to chemical cleaning, the effects of heat treatment on strength and surface condition, and the effect of mechanical properties on strength and weldability.

  15. Controlled powder morphology experiments in megabar 304 stainless steel compaction

    SciTech Connect

    Staudhammer, K.P.; Johnson, K.A.

    1985-01-01

    Experiments with controlled morphology including shape, size, and size distribution were made on 304L stainless steel powders. These experiments involved not only the powder variables but pressure variables of 0.08 to 1.0 Mbar. Also included are measured container strain on the material ranging from 1.5% to 26%. Using a new strain controllable design it was possible to seperate and control, independently, strain and pressure. Results indicate that powder morphology, size distribution, packing density are among the pertinent parameters in predicting compaction of these powders.

  16. Evaluation of tantalum 316 stainless steel transition joints

    NASA Technical Reports Server (NTRS)

    Stoner, D. R.

    1972-01-01

    Tubular transition joints providing a metallurgically bonded connection between tantalum and 316 stainless steel pipe sections were comparatively evaluated for durability under thermal cycling conditions approximating the operation of a SNAP-8 mercury boiler. Both coextruded and vacuum brazed transition joints of 50mm (2 inch) diameter were tested by thermal cycling 100 times between 730 C and 120 C(1350 F and 250 F) in a high vacuum environment. The twelve evaluated transition joints survived the full test sequence without developing leaks, although liquid penetrant bond line indications eventually developed in all specimens. The brazed transition joints exhibited the best dimensional stability and bond line durability.

  17. 75 FR 67110 - Forged Stainless Steel Flanges From India and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... stainless steel flanges from India and Taiwan (65 FR 49964). Following second five-year reviews by Commerce... duty orders on imports of forged stainless steel flanges from India and Taiwan (71 FR 3457, January 23... part 201), and part 207, subparts A, D, E, and F (19 CFR part 207), as most recently amended at 74...

  18. 77 FR 41754 - Drawn Stainless Steel Sinks From the People's Republic of China: Postponement of Preliminary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-16

    ...'s Republic of China: Initiation of Antidumping Duty Investigation, 77 FR 18207 (March 27, 2012). On... International Trade Administration Drawn Stainless Steel Sinks From the People's Republic of China: Postponement...'') initiated an antidumping duty investigation on drawn stainless steel sinks from the People's Republic...

  19. 78 FR 21596 - Drawn Stainless Steel Sinks From the People's Republic of China: Countervailing Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-11

    ... Countervailing Duty Determination, 78 FR 13017 (February 26, 2013). \\2\\ See Drawn Stainless Steel Sinks from... From the People's Republic of China: Preliminary Affirmative Countervailing Duty Determination, 77 FR... International Trade Administration Drawn Stainless Steel Sinks From the People's Republic of...

  20. 78 FR 45271 - Welded Stainless Steel Pressure Pipe From Malaysia, Thailand, and Vietnam

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ... Commission, Washington, DC, and by publishing the notice in the Federal Register of May 24, 2013 (78 FR 31574... COMMISSION Welded Stainless Steel Pressure Pipe From Malaysia, Thailand, and Vietnam Determination On the... injured by reason of imports from Malaysia, Thailand, and Vietnam of welded stainless steel pressure...

  1. 75 FR 53714 - Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... imports of stainless steel butt-weld pipe fittings from Japan (53 FR 9787). On February 23, 1993, Commerce... on imports of stainless steel butt-weld pipe fittings from Japan, Korea, and Taiwan (65 FR 11766... Japan, Korea, and Taiwan (70 FR 61119). The Commission is now conducting third reviews to...

  2. 77 FR 41969 - Stainless Steel Bar From Japan: Rescission of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-17

    ... Revocation in Part, and Deferral of Administrative Review, 77 FR 19179, 19181 (March 30, 2012). Based on a... International Trade Administration Stainless Steel Bar From Japan: Rescission of Antidumping Duty Administrative...) initiated an administrative review of the antidumping duty order on stainless steel bar from Japan...

  3. 75 FR 59744 - Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-28

    ... group response to its notice of institution (75 FR 30437, June 1, 2010) was adequate and that the... COMMISSION Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan AGENCY... Korea and the antidumping duty orders on stainless steel sheet and strip from Germany, Italy,...

  4. 75 FR 76025 - Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... party responded to the sunset review notice of initiation by the applicable deadline * * *'' (75 FR... COMMISSION Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan AGENCY: United States... stainless steel butt-weld pipe fittings from Japan, Korea, and Taiwan would be likely to lead...

  5. 78 FR 63517 - Control of Ferrite Content in Stainless Steel Weld Metal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... Information The NRC published DG-1279 in the Federal Register on October 3, 2012 (77 FR 60479), for a 60-day... COMMISSION Control of Ferrite Content in Stainless Steel Weld Metal AGENCY: Nuclear Regulatory Commission... revision to Regulatory Guide (RG) 1.31, ``Control of Ferrite Content in Stainless Steel Weld Metal.''...

  6. Corrosion characteristics of ferric and austenitic stainless steels for dental magnetic attachment.

    PubMed

    Endo, K; Suzuki, M; Ohno, H

    2000-03-01

    The corrosion behaviors of four ferric stainless steels and two austenitic stainless steels were examined in a simulated physiological environment (0.9% NaCl solution) to obtain basic data for evaluating the appropriate composition of stainless steels for dental magnetic attachments. The corrosion resistance was evaluated by electrochemical techniques and the analysis of released metal ions by atomic absorption spectrophotometry. The surface of the stainless steels was analyzed by X-ray photoelectron spectroscopy (XPS). The breakdown potential of ferric stainless steels increased and the total amount of released metal ions decreased linearly with increases in the sum of the Cr and Mo contents. The corrosion rate of the ferric stainless steels increased 2 to 6 times when they were galvanically coupled with noble metal alloys but decreased when coupled with commercially pure Ti. For austenitic stainless steels, the breakdown potential of high N-bearing stainless steel was approximately 500 mV higher than that of SUS316L, which is currently used as a component in dental magnetic attachments. The enriched nitrogen at the alloy/passive film interface may be effective in improving the localized corrosion resistance. PMID:11219089

  7. 77 FR 3231 - Certain Stainless Steel Wire Rods From India: Continuation of Antidumping Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-23

    ... [Federal Register Volume 77, Number 14 (Monday, January 23, 2012)] [Notices] [Pages 3231-3232] [FR... (``Sunset'') Review, 76 FR 38613 (July 1, 2011); see also Stainless Steel Wire Rod From India; Institution..., 76 FR 38686 (July 1, 2011). \\1\\ Antidumping Duty Order: Certain Stainless Steel Wire Rods from...

  8. 77 FR 13631 - Drawn Stainless Steel Sinks From China; Institution and Scheduling of Preliminary Phase...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... COMMISSION Drawn Stainless Steel Sinks From China; Institution and Scheduling of Preliminary Phase... the United States is materially retarded, by reason of imports from China of drawn stainless steel... amended. The amendments took effect on November 7, 2011. See 76 FR 61937 (Oct. 6, 2011) and the...

  9. 77 FR 58355 - Drawn Stainless Steel Sinks From the People's Republic of China: Countervailing Duty Investigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-20

    ... Countervailing Duty Determination: Drawn Stainless Steel Sinks From the People's Republic of China, 77 FR 46717...: Initiation of Countervailing Duty Investigation, 77 FR 18211 (March 27, 2012), and, also, see Drawn Stainless Steel Sinks From the People's Republic of China: Initiation of Antidumping Duty Investigation, 77...

  10. Assessment of bacterial biofilm on stainless steel by hyperspectral fluorescence imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hyperspectral fluorescence imaging techniques were investigated for detection of two genera of microbial biofilms on stainless steel material which is commonly used to manufacture food processing equipment. Stainless steel coupons were deposited in nonpathogenic E. coli O157:H7 and Salmonella cultu...

  11. 76 FR 69292 - Aging Management of Stainless Steel Structures and Components in Treated Borated Water

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    .... ML100920158), for which a notice of availability was published in the Federal Register on June 22, 2010 (75 FR... COMMISSION Aging Management of Stainless Steel Structures and Components in Treated Borated Water AGENCY... Staff Guidance (LR-ISG), LR- ISG-2011-01, ``Aging Management of Stainless Steel Structures...

  12. Beneficially reusing LLRW the Savannah River Site Stainless Steel Program

    SciTech Connect

    Boettinger, W.L.

    1993-09-09

    With 68 radioactively contaminated excess Process Water Heat Exchangers the Savannah River Site launched its program to turn potential LLRW metal liabilities into assets. Each Heat Exchanger contains approximately 100 tons of 304 Stainless Steel and could be disposed as LLRW by land burial. Instead the 7000 tons of metal will be recycled into LLRW, HLW, and TRU waste containers thereby eliminating the need for near term land disposal and also eliminating the need to add more clean metal to the waste stream. Aspects of the partnership between DOE and Private Industry necessary to accomplish this new mission are described. A life cycle cost analysis associated with past practices of using carbon steel containers to indefinitely store material (contributing to the creation of today`s legacy waste problems) is presented. The avoided cost calculations needed to support the economics of the ``Indifference`` decision process in assessing the Beneficial Reuse option relative to the Burial option are described.

  13. Stainless Steels with Improved Oxidation Resistance for Recuperators

    SciTech Connect

    Pint, Bruce A

    2006-01-01

    New materials are being evaluated to replace type 347 stainless steel in microturbine recuperators operating at higher temperatures in order to increase the efficiency of the microturbine. Commercial alloys 120 and 625 are being tested along with potentially lower cost substitutes, such as Fe-20Cr-25Ni and Fe-20Cr-20Ni. Long-term testing of these materials at 650--700 C shows excellent corrosion resistance to a simulated exhaust gas environment. Testing at 800 C has been used to further differentiate the performance of the various materials. The depletion of Cr from foils of these materials is being used to evaluate the rate of attack. Although those alloys with the highest Ni and Cr contents have longer lives in this environment, lower alloyed steels may have sufficient protection at a lower cost.

  14. Stress corrosion cracking of duplex stainless steels in caustic solutions

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Ananya

    Duplex stainless steels (DSS) with roughly equal amount of austenite and ferrite phases are being used in industries such as petrochemical, nuclear, pulp and paper mills, de-salination plants, marine environments, and others. However, many DSS grades have been reported to undergo corrosion and stress corrosion cracking in some aggressive environments such as chlorides and sulfide-containing caustic solutions. Although stress corrosion cracking of duplex stainless steels in chloride solution has been investigated and well documented in the literature but the SCC mechanisms for DSS in caustic solutions were not known. Microstructural changes during fabrication processes affect the overall SCC susceptibility of these steels in caustic solutions. Other environmental factors, like pH of the solution, temperature, and resulting electrochemical potential also influence the SCC susceptibility of duplex stainless steels. In this study, the role of material and environmental parameters on corrosion and stress corrosion cracking of duplex stainless steels in caustic solutions were investigated. Changes in the DSS microstructure by different annealing and aging treatments were characterized in terms of changes in the ratio of austenite and ferrite phases, phase morphology and intermetallic precipitation using optical micrography, SEM, EDS, XRD, nano-indentation and microhardness methods. These samples were then tested for general and localized corrosion susceptibility and SCC to understand the underlying mechanisms of crack initiation and propagation in DSS in the above-mentioned environments. Results showed that the austenite phase in the DSS is more susceptible to crack initiation and propagation in caustic solutions, which is different from that in the low pH chloride environment where the ferrite phase is the more susceptible phase. This study also showed that microstructural changes in duplex stainless steels due to different heat treatments could affect their SCC

  15. The retention of iodine in stainless steel sample lines

    SciTech Connect

    Evans, G.J.; Deir, C.; Ball, J.M.

    1995-02-01

    Following an accident in a multi-unit CANDU nuclear generating station, decontamination of air vented from containment would play a critical role in minimizing the release of iodine to the environment. The concentration of gas phase iodine in containment air would be measured using the post accident radiation monitoring system, requiring that air samples be passed through a considerable length of tubing to a remote location where the desired measurements could safely be made. A significant loss of iodine, due to adsorption on the sample line surfaces, could greatly distort the measurement. In this study, the retention of I{sub 2}(g) on stainless steel was evaluated in bench scale experiments in order to evaluate, and if possible minimise, the extent of any such line losses. Experiments at the University of Toronto were performed using 6 inch lengths of 1/4 inch stainless steel tubing. Air, containing I-131 labelled I{sub 2}(g), ranging in concentration from 10{sup {minus}10} to 10{sup {minus}6} mol/dm{sup 3} and relative humidity (:RH) from 20 to 90 %, was passed through tubing samples maintained at temperatures ranging from 25 to 90{degrees}C. Adsorption at low gas phase iodine concentrations differed substantially from that at higher concentrations. The rate of deposition was proportional to the gas phase concentration, giving support to the concept of a first order deposition velocity. The surface loading increased with increasing relative humidity, particularly at low RH values, while the deposition rate decreased with increasing temperature. Surface water on the steel may play an important role in the deposition process. The chemisorbed iodine was located primarily in areas of corrosion. Furthermore, water used to wash the steel contained Fe, Mn and iodine in the form of iodide, suggesting that I{sub 2} reacted to form metal iodides. The deposition of I{sub 2} was also found to depend on the initial surface condition.

  16. Study on tempering behaviour of AISI 410 stainless steel

    SciTech Connect

    Chakraborty, Gopa; Das, C.R.; Albert, S.K.; Bhaduri, A.K.; Thomas Paul, V.; Panneerselvam, G.; Dasgupta, Arup

    2015-02-15

    Martensitic stainless steels find extensive applications due to their optimum combination of strength, hardness and wear-resistance in tempered condition. However, this class of steels is susceptible to embrittlement during tempering if it is carried out in a specific temperature range resulting in significant reduction in toughness. Embrittlement of as-normalised AISI 410 martensitic stainless steel, subjected to tempering treatment in the temperature range of 673–923 K was studied using Charpy impact tests followed by metallurgical investigations using field emission scanning electron and transmission electron microscopes. Carbides precipitated during tempering were extracted by electrochemical dissolution of the matrix and identified by X-ray diffraction. Studies indicated that temper embrittlement is highest when the steel is tempered at 823 K. Mostly iron rich carbides are present in the steel subjected to tempering at low temperatures of around 723 K, whereas chromium rich carbides (M{sub 23}C{sub 6}) dominate precipitation at high temperature tempering. The range 773–823 K is the transition temperature range for the precipitates, with both Fe{sub 2}C and M{sub 23}C{sub 6} types of carbides coexisting in the material. The nucleation of Fe{sub 2}C within the martensite lath, during low temperature tempering, has a definite role in the embrittlement of this steel. Embrittlement is not observed at high temperature tempering because of precipitation of M{sub 23}C{sub 6} carbides, instead of Fe{sub 2}C, preferentially along the lath and prior austenite boundaries. Segregation of S and P, which is widely reported as one of the causes for temper embrittlement, could not be detected in the material even through Auger electron spectroscopy studies. - Highlights: • Tempering behaviour of AISI 410 steel is studied within 673–923 K temperature range. • Temperature regime of maximum embrittlement is identified as 773–848 K. • Results show that type of

  17. Applications and experiences with super duplex stainless steel in wet FGD scrubber systems

    SciTech Connect

    Francis, R.; Byrne, G.; Warburton, G.; Hebdon, S.

    1998-12-31

    The paper presents the properties of the author`s company`s proprietary super duplex stainless steel. Work is presented showing the development of a more realistic laboratory solution representing typical limestone slurries found in real flue gas desulfurization (FGD) systems. The importance of additions of metal ions such as Fe{sup 3+} and Mn{sup 2+} as well as partially oxidized sulfur species is demonstrated. Results are presented comparing the crevice corrosion resistance of super duplex stainless steel in these slurries with other commonly used wrought and cast stainless steels, for both simulated anthracite and lignite type slurries. Data from loop tests on the erosion resistance of a range of alloys in simulated FGD slurries is presented. The results clearly show the superior resistance of super duplex stainless steel to both crevice corrosion and erosion in FGD slurries. Finally the experiences in UK FGD systems with both cast and wrought super duplex stainless steel are presented.

  18. Biocompatibility of 17-4 PH stainless steel foam for implant applications.

    PubMed

    Mutlu, Ilven; Oktay, Enver

    2011-01-01

    In this study, biocompatibility of 17-4 PH stainless steel foam for biomedical implant applications was investigated. 17-4 PH stainless steel foams having porosities in the range of 40-82% with an average pore size of around 600 μm were produced by space holder-sintering technique. Sintered foams were precipitation hardened for times of 1-6 h at temperatures between 450-570 °C. Compressive yield strength and Young's modulus of aged stainless steel foams were observed to vary between 80-130 MPa and 0.73-1.54 GPa, respectively. Pore morphology, pore size and the mechanical properties of the 17-4 PH stainless steel foams were close to cancellous bone. In vitro evaluations of cytotoxicity of the foams were investigated by XTT and MTT assays and showed sufficient biocompatibility. Surface roughness parameters of the stainless steel foams were also determined to characterize the foams. PMID:22182790

  19. Type 304L stainless steel surface microstructure: Performance in hydride storage and acid cleaning

    SciTech Connect

    Clark, E.A.

    1994-07-01

    The performance of stainless steel as the container in hydride storage bed systems has been evaluated, primarily using scanning electron microscopy. No adverse reaction between Type 304L stainless steel and either LaNi{sub 5{minus}x},Al{sub x}, or palladium supported on Kieselguhr granules (silica) during exposure in hydrogen was found in examination of retired prototype storage bed containers and special compatibility test samples. Intergranular surface ditching, observed on many of the stainless steel surfaces examined, was shown to result from air annealing and acid cleaning of stainless steel during normal fabrication. The ditched air annealed and acid cleaned stainless steel samples were more resistant to subsequent acid attack than vacuum annealed or polished samples without ditches.

  20. 76 FR 38686 - Stainless Steel Wire Rod From India; Institution of a Five-Year Review Concerning the Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... on imports of stainless steel wire rod from India (58 FR 63335). Following first five-year reviews by... duty order on imports of stainless steel wire rod from India (65 FR 47403). Following second five-year... antidumping duty order on imports of stainless steel wire rod from India (71 FR 45023). The Commission is...

  1. 76 FR 64106 - Certain Welded Stainless Steel Pipe From Korea and Taiwan; Scheduling of Expedited Five-Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-17

    ... COMMISSION Certain Welded Stainless Steel Pipe From Korea and Taiwan; Scheduling of Expedited Five-Year Reviews Concerning the Antidumping Duty Orders on Certain Welded Stainless Steel Pipe From Korea and... duty orders on certain welded stainless steel pipe (specifically ASTM A-312 pipe) from Korea and...

  2. 75 FR 27987 - Certain Welded Stainless Steel Pipes From the Republic of Korea: Final Results of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-19

    ... Antidumping Duty Order: Certain Welded Stainless Steel Pipe From the Republic of Korea, 60 FR 10064, 10065... International Trade Administration Certain Welded Stainless Steel Pipes From the Republic of Korea: Final... welded stainless steel pipes (WSSP) from the Republic of Korea (Korea). This review covers one...

  3. 77 FR 24459 - Stainless Steel Butt-Weld Pipe Fittings From Italy: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-24

    ... International Trade Administration Stainless Steel Butt-Weld Pipe Fittings From Italy: Final Results of... stainless steel butt-weld pipe fittings (SSBW pipe fittings) from Italy.\\1\\ This review covers two... results remain unchanged from the preliminary results of review. \\1\\ See Stainless Steel Butt-Weld...

  4. 78 FR 22227 - Stainless Steel Bar From Brazil: Final Results of Antidumping Duty Administrative Review; 2011-2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-15

    ...: Stainless Steel Bar from Brazil, India and Japan, 60 FR 9661 (February 21, 1995). Changes Since the... International Trade Administration Stainless Steel Bar From Brazil: Final Results of Antidumping Duty... preliminary results of the administrative review of the antidumping duty order on stainless steel bar...

  5. 76 FR 13357 - Stainless Steel Sheet and Strip in Coils From Mexico; Correction Notice to Amended Final Results...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ... International Trade Administration Stainless Steel Sheet and Strip in Coils From Mexico; Correction Notice to... administrative review for stainless steel sheet and strip in coils from Mexico. See Stainless Steel Sheet and..., 76 FR 9542 (February 18, 2011) (Amended Final Results). The Amended Final Results states...

  6. 76 FR 67672 - Certain Stainless Steel Wire Rods From India: Final Results of the Expedited Sunset Review of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ...\\ Antidumping Duty Order: Certain Stainless Steel Wire Rods from India, 58 FR 63335 (December 1, 1993). The... International Trade Administration Certain Stainless Steel Wire Rods From India: Final Results of the Expedited...) initiated the third sunset review of the antidumping duty order on certain stainless steel wire rods...

  7. 76 FR 56401 - Stainless Steel Bar from India: Final Results of the Antidumping Duty Administrative Review, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-13

    ...: Stainless Steel Bar from India, 59 FR 66915 (December 28, 1994). These cash deposit requirements, when... International Trade Administration Stainless Steel Bar from India: Final Results of the Antidumping Duty.... Finally, we are announcing our revocation of the order on stainless steel bar from India, in part,...

  8. 76 FR 38688 - Certain Welded Stainless Steel Pipe From Korea and Taiwan; Institution of a Five-Year Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... ASTM A-312 stainless steel pipe from Korea (57 FR 62301) and Taiwan (57 FR 62300). Following first five... ASTM A-312 stainless steel pipe from Korea and Taiwan (71 FR 53412, September 11, 2006). The Commission... as all welded stainless steel pipes and pressure tubes, excluding grade 409 tubes and...

  9. Quality control and assurance program for duplex stainless steels, field experience

    SciTech Connect

    Mekhjian, M.; Richard, D.; Nemzer, A.

    1994-12-31

    Duplex stainless steels have proven to be cost effective alternatives to more highly alloyed materials in chloride environments in which conventional 300 series austenitic stainless steels suffer from stress corrosion cracking. However, improper welding of these alloys can cause significant reduction in their corrosion resistance. Close monitoring of welding during fabrication and tight quality control is necessary to ensure that sound weld metal microstructure is obtained with optimum corrosion resistance. One of FMC`s primary applications for duplex stainless steels has been in large scrubbers units in chemical processing plants. In the fabrication of these scrubbers, training of the fabricators and welders was necessary as a part of the total quality control and assurance program. Corrosion testing was performed on coupons removed from each welding procedure qualification test plate and from run-off tabs removed from production welds. The corrosion tests were performed in ferric chloride. Although ferric chloride is not a realistic service environment for these alloys, it has been widely used for screening purposes and successfully indicates the presence of undesirable microstructures. Two deposited weld microstructures were identified as being most susceptible to pitting in the samples examined. These were areas with high ferrite containing precipitates and reheated areas of multiple pass welds with a high secondary austenite content. Field experience showed that relying only on monitoring and controlling the welding heat input, preheat and interpass temperatures, may not be sufficient for ensuring the corrosion resistance of the finished weldment and additional corrosion testing should be done. The materials tested were weldments of alloy 2205 (UNS S31803) and alloy 255 (LTNS S32550).

  10. Strength comparison of allogenic bone screws, bioabsorbable screws, and stainless steel screw fixation.

    PubMed

    Rano, James A; Savoy-Moore, Ruth T; Fallat, Lawrence M

    2002-01-01

    Allogenic bone screws are new to the fixation market and have yet to be tested against current fixation materials. An in vitro comparison of the same sizes of stainless steel, bioabsorbable, and allogenic bone screws was undertaken to assess screw resistance to the forces of bending, pullout, and shear. Using aluminum plates to support the screws, forces up to 1000 Newtons were applied to six to eight samples of each type of screw. During each test, stainless steel screws withstood the maximum force that could be exerted by the testing apparatus without failing (bending, 113.9 +/- 11.8 N mean +/- SE; pullout 999.1 +/- 33.7 N; and shear, 997.5 +/- 108.8 N). In each test, compared to bioabsorbable screws, allogenic bone screws failed faster (pullout, allogenic: 12.4 +/- 1.1 seconds vs. bioabsorbable, 120.6 +/- 13.8 seconds; p = .001; bending, allogenic: 53.4 +/- 4.8 seconds vs. bioabsorbable, 201.9 +/- 11.1 seconds; p = .001; shear, allogenic 13.5 +/- 1.4 seconds vs. bioabsorbable, 43.8 +/- 0.9 seconds; p = .001) under equivalent (pullout: bioabsorbable, 385.0 +/- 18.4 N vs. allogenic, 401.0 +/- 35.9 N; p = .001) or lower (bending, allogenic: 4.7 +/- 0.2 N vs. bioabsorbable, 11.0 +/- 0.9 N; p = .675; shear, allogenic: 312.1 +/- 15.5 N vs. bioabsorbable 680.9 +/- 8.5 N; p = .001) loads, and in a highly variable fashion. Overall, the bioabsorbable screws withstood the forces of bending, pullout, and shear better than the allogenic screws, and stainless steel screws outperformed both bioabsorbable and allogenic screws. Despite these results, allogenic screws could still be useful in compliant patients who would benefit from their osteoconductive properties. PMID:11858609

  11. Stainless steel corrosion by molten nitrates : analysis and lessons learned.

    SciTech Connect

    Kruizenga, Alan Michael

    2011-09-01

    A secondary containment vessel, made of stainless 316, failed due to severe nitrate salt corrosion. Corrosion was in the form of pitting was observed during high temperature, chemical stability experiments. Optical microscopy, scanning electron microscopy and energy dispersive spectroscopy were all used to diagnose the cause of the failure. Failure was caused by potassium oxide that crept into the gap between the primary vessel (alumina) and the stainless steel vessel. Molten nitrate solar salt (89% KNO{sub 3}, 11% NaNO{sub 3} by weight) was used during chemical stability experiments, with an oxygen cover gas, at a salt temperature of 350-700 C. Nitrate salt was primarily contained in an alumina vessel; however salt crept into the gap between the alumina and 316 stainless steel. Corrosion occurred over a period of approximately 2000 hours, with the end result of full wall penetration through the stainless steel vessel; see Figures 1 and 2 for images of the corrosion damage to the vessel. Wall thickness was 0.0625 inches, which, based on previous data, should have been adequate to avoid corrosion-induced failure while in direct contact with salt temperature at 677 C (0.081-inch/year). Salt temperatures exceeding 650 C lasted for approximately 14 days. However, previous corrosion data was performed with air as the cover gas. High temperature combined with an oxygen cover gas obviously drove corrosion rates to a much higher value. Corrosion resulted in the form of uniform pitting. Based on SEM and EDS data, pits contained primarily potassium oxide and potassium chromate, reinforcing the link between oxides and severe corrosion. In addition to the pitting corrosion, a large blister formed on the side wall, which was mainly composed of potassium, chromium and oxygen. All data indicated that corrosion initiated internally and moved outward. There was no evidence of intergranular corrosion nor were there any indication of fast pathways along grain boundaries. Much of the

  12. Development of cryogenic thermal control heat pipes. [of stainless steels

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The development of thermal control heat pipes that are applicable to the low temperature to cryogenic range was investigated. A previous effort demonstrated that stainless steel axially grooved tubing which met performance requirements could be fabricated. Three heat pipe designs utilizing stainless steel axially grooved tubing were fabricated and tested. One is a liquid trap diode heat pipe which conforms to the configuration and performance requirements of the Heat Pipe Experiment Package (HEPP). The HEPP is scheduled for flight aboard the Long Duration Flight Exposure Facility (LDEF). Another is a thermal switch heat pipe which is designed to permit energy transfer at the cooler of the two identical legs. The third thermal component is a hybrid variable conductance heat pipe (VCHP). The design incorporates both a conventional VCHP system and a liquid trap diode. The design, fabrication and thermal testing of these heat pipes is described. The demonstrated heat pipe behavior including start-up, forward mode transport, recovery after evaporator dry-out, diode performance and variable conductance control are discussed.

  13. Intergranular stress distributions in polycrystalline aggregates of irradiated stainless steel

    NASA Astrophysics Data System (ADS)

    Hure, J.; El Shawish, S.; Cizelj, L.; Tanguy, B.

    2016-08-01

    In order to predict InterGranular Stress Corrosion Cracking (IGSCC) of post-irradiated austenitic stainless steel in Light Water Reactor (LWR) environment, reliable predictions of intergranular stresses are required. Finite elements simulations have been performed on realistic polycrystalline aggregate with recently proposed physically-based crystal plasticity constitutive equations validated for neutron-irradiated austenitic stainless steel. Intergranular normal stress probability density functions are found with respect to plastic strain and irradiation level, for uniaxial loading conditions. In addition, plastic slip activity jumps at grain boundaries are also presented. Intergranular normal stress distributions describe, from a statistical point of view, the potential increase of intergranular stress with respect to the macroscopic stress due to grain-grain interactions. The distributions are shown to be well described by a master curve once rescaled by the macroscopic stress, in the range of irradiation level and strain considered in this study. The upper tail of this master curve is shown to be insensitive to free surface effect, which is relevant for IGSCC predictions, and also relatively insensitive to small perturbations in crystallographic texture, but sensitive to grain shapes.

  14. Aging degradation of cast stainless steel: status and program

    SciTech Connect

    Chopra, O.K.; Ayrault, G.

    1983-10-01

    A program has been initiated to investigate the significance of in-service embrittlement of cast duplex stainless steels under light-water reactor operating conditions. The existing data are reviewed to determine the critical parameters that control the aging behavior and to define the objectives and scope of the investigation. The test matrices for microstructural studies and mechanical property measurements are presented. The initial experimental effort is focussed on characterizing the microstructure of long-term, low-temperature aged material. Specimens from three heats of cast CF-8 and CF-8M stainless steel aged for up to 70,000 h at 300, 350, and 400/sup 0/C were obtained from George Fisher Ltd., of Switzerland. Initial analyses reveal the formation of three different types of precipitates which are not ..cap alpha..'. An FCC phase, similar to the M/sub 23/C/sub 6/ precipitates, was present in all the long-term aged material. 15 references, 10 figures, 2 tables.

  15. IN-SITU MEASUREMENT OF TRITIUM PERMEATION THROUGH STAINLESS STEEL

    SciTech Connect

    Luscher, Walter G.; Senor, David J.; Clayton, Kevin; Longhurst, Glen R.

    2013-06-01

    The TMIST-2 irradiation experiment was conducted in the Advanced Test Reactor at Idaho National Laboratory to evaluate tritium permeation through Type 316 stainless steel (316 SS). The interior of a 316 SS seamless tube specimen was exposed to a 4He carrier gas mixed with a specified quantity of tritium (T2) to yield partial pressures of 0.1, 5, and 50 Pa at 292° and 330°C. In-situ tritium permeation measurements were made by passing a He-Ne sweep gas over the outer surface of the specimen to carry the permeated tritium to a bubbler column for liquid scintillation counting. An irradiation enhancement factor (IEF) was determined by comparing in-situ permeation data with a correlation for ex-reactor hydrogen permeation through austenitic stainless steel developed from literature data and reported by Le Claire. Nominal values for the IEF ranged between 3 and 5 for 316 SS. In-situ permeation data were also used to derive an in-reactor permeation correlation as a function of temperature and pressure. In addition, the triton recoil contribution to tritium permeation, which results from the transmutation of 3He to T, was also evaluated by introducing a 4He carrier gas mixed with 3He at a partial pressure of 1013 Pa at 330°C. Less than 3% of the tritium resulting from 3He transmutation contributed to tritium permeation.

  16. In Situ Measurement of Tritium Permeation Through Stainless Steel

    SciTech Connect

    Luscher, Walter G.; Senor, David J.; Clayton, Kevin; Longhurst, Glen

    2013-06-01

    The TMIST-2 irradiation experiment was conducted in the Advanced Test Reactor at Idaho National Laboratory to evaluate tritium permeation through Type 316 stainless steel (316 SS). The interior of a 316 SS seamless tube specimen was exposed to a 4He carrier gas mixed with a specified quantity of tritium (T2) to yield partial pressures of 0.1, 5, and 50 Pa at 292° and 330°C. In-situ tritium permeation measurements were made by passing a He-Ne sweep gas over the outer surface of the specimen to carry the permeated tritium to a bubbler column for liquid scintillation counting. An irradiation enhancement factor (IEF) was determined by comparing in-situ permeation data with a correlation for ex-reactor hydrogen permeation through austenitic stainless steel developed from literature data and reported by Le Claire. Nominal values for the IEF ranged between 3 and 5 for 316 SS. In-situ permeation data were also used to derive an in-reactor permeation correlation as a function of temperature and pressure. In addition, the triton recoil contribution to tritium permeation, which results from the transmutation of 3He to T, was also evaluated by introducing a 4He carrier gas mixed with 3He at a partial pressure of 1013 Pa at 330°C. Less than 3% of the tritium resulting from 3He transmutation contributed to tritium permeation.

  17. Processing fine stainless-steel slag using spiral concentration.

    PubMed

    Wolfe, Eric R; Klima, Mark S

    2008-04-01

    In this study, the effectiveness of spiral concentration to process a fine (-1 mm) stainless-steel slag was evaluated. Specifically, testing was conducted to determine the feasibility of producing a high metal content stainless steel product and a low metal content aggregate product. This involved investigating a key operating variable for both five-and seven-turn spiral concentrators. The raw slag and spiral products were characterized to determine their respective size and metal distributions. Separation testing was carried out using the two full-scale spiral concentrators to evaluate the effects of feed solids concentration on spiral performance at solids feed rates ranging from 15 to 30 kg/min. The results indicated that under certain conditions, a high-quality metal fraction could be produced. For example, using the five-turn spiral, a product containing 95% metal was obtained at a low metal recovery. Both spirals were ineffective at concentrating the aggregate fraction. Overall, the feed solids concentration did not significantly affect the quality or recoveries of the products, particularly for feed solids concentrations less than 35% by weight. In order to improve the metal recoveries and to produce a low-metal aggregate material, reprocessing of the product streams and/or additional liberation of the raw slag would be required. PMID:18324536

  18. Thermal treatment effects on laser surface remelting duplex stainless steel

    NASA Astrophysics Data System (ADS)

    do Nascimento, Alex M.; Ierardi, Maria Clara F.; Aparecida Pinto, M.; Tavares, Sérgio S. M.

    2008-10-01

    In this paper the microstructural changes and effects on corrosion resistance of duplex stainless steels UNS S32304 and UNS S32205, commonly used by the petroleum industry, were studied, following the execution of laser surface remelting (LSM) and post-thermal treatments (TT). In this way, data was obtained, which could then be compared with the starting condition of the alloys. In order to analyze the corrosion behaviour of the alloys in the as-received conditions, treated with laser and after post-thermal treatments, cyclic polarization tests were carried out. A solution of 3.5% NaCl (artificial sea water) was used, as duplex stainless steels are regularly used by the petroleum industry in offshore locations. The results obtained showed that when laser surface treated, due to rapid resolidification, the alloys became almost ferritic, and since the level of nitrogen in the composition of both alloys is superior to their solubility limit in ferrite, a precipitation of Cr2N (chromium nitrides) occurred in the ferritic matrix, causing loss of corrosion resistance, thus resulting in an increase in surface hardness. However, after the post-thermal treatment the alloys corrosion resistance was restored to values close to those of the as-received condition.

  19. Nitrogen containing shielding gases for GTAW duplex stainless steels

    SciTech Connect

    Creffield, G.K.; Cole, M.H.; Paciej, R.; Huang, W.; Urmston, S.

    1993-12-31

    The duplex stainless steel are alloys characterized as consisting of two phases; austenite and ferrite. As such, they combine the benefits of both phases i.e. good ductility and general corrosion resistance of austenite, but with improved stress corrosion cracking resistance and strength associate with ferrite. Carefully controlled manufacturing techniques are employed to produce this combination in roughly equal proportions to ensure optimum properties. The range of duplex alloys studied in this work covered both the standard grade (2205) and the latest generation of super duplex (2507) alloys; typical compositions are shown in Table 1. Although the standard duplex is the most commonly available and widely used, super duplexes, which are characterized by higher chromium, nickel, molybdenum and nitrogen contents, have even better corrosion properties and are finding increasing applications in the offshore industry. To benefit from the superior properties of duplex, it is vital that these alloys can be welded effectively and that the properties of the welded joint match those of the parent weld. The objective of the current investigation was to study the effect of nitrogen, in both the shielding and purge gas, on the weld metal nitrogen content, microstructure and corrosion resistance, with the eventual aim of recommending an effective shielding gas mixture for duplex stainless steels.

  20. Fusion welding of a modern borated stainless steel

    SciTech Connect

    Robino, C.V.; Cieslak, M.J.

    1997-01-01

    Experiments designed to assess the fabrication and service weldability of 304B4A borated stainless steel were conducted. Welding procedures and parameters for manual gas tungsten arc (GTA) welding, autogenous electron beam (EB) welding and filler-added EB welding were developed and found to be similar to those for austenitic stainless steels. Following the procedure development, four test welds were produced and evaluated by microstructural analysis and Charpy impact testing. Further samples were used for determination of the postweld heat treatment (PWHT) response of the welds. The fusion zone structure of welds in this alloy consists of primary austenite dendrites with an interdendritic eutectic-like austenite/boride constituent. Welds also show an appreciable partially molten zone that consists of the austenite/boride eutectic surrounding unmelted austenite islands. The microstructure of the EB welds was substantially finer than that of the GTA welds, and boride coarsening was not observed in the solid state heat-affected zone (HAZ) of either weld type. The impact toughness of as-welded samples was found to be relatively poor, averaging less than 10 J for both GTA and EB welds. For fusion zone notched GTA and EB samples and centerline notched EB samples, fracture generally occurred along the boundary between the partially molten and solid-state regions of the HAZ. The results of the PWHT study were very encouraging, with typical values of the impact energy for HAZ notched samples approaching 40 J, or twice the minimum code-acceptable value.

  1. A porous stainless steel membrane system for extraterrestrial crop production

    NASA Technical Reports Server (NTRS)

    Koontz, H. V.; Prince, R. P.; Berry, W. L.; Knott, W. M. (Principal Investigator)

    1990-01-01

    A system was developed in which nutrient flow to plant roots is controlled by a thin (0.98 or 1.18 mm) porous (0.2 or 0.5 microns) stainless steel sheet membrane. The flow of nutrient solution through the membrane is controlled by adjusting the relative negative pressure on the nutrient solution side of the membrane. Thus, the nutrient solution is contained by the membrane and cannot escape from the compartment even under microgravity conditions if the appropriate pressure gradient across the membrane is maintained. Plant roots grow directly on the top surface of the membrane and pull the nutrient solution through this membrane interface. The volume of nutrient solution required by this system for plant growth is relatively small, since the plenum, which contains the nutrient solution in contact with the membrane, needs only to be of sufficient size to provide for uniform flow to all parts of the membrane. Solution not passing through the membrane to the root zone is recirculated through a reservoir where pH and nutrient levels are controlled. The size of the solution reservoir depends on the sophistication of the replenishment system. The roots on the surface of the membrane are covered with a polyethylene film (white on top, black on bottom) to maintain a high relative humidity and also limit light to prevent algal growth. Seeds are sown directly on the stainless steel membrane under the holes in the polyethylene film that allow a pathway for the shoots.

  2. The diffusivity of hydrogen in Nb stabilized stainless steel

    NASA Technical Reports Server (NTRS)

    Outlaw, R. A.; Peterson, D. T.

    1983-01-01

    The evolution of hydrogen from 347 stainless steel has been studied by using a real time dynamic technique under ultrahigh vacuum conditions. Auger electron spectroscopy was used to determine the surface composition as a function of time and temperature. The surface film on the electropolished samples was found to be approximately 15 A thick and consisted of a carbon-oxygen complex and a metal oxide (FexOy). Upon heating to 400 C, the carbon-oxygen complex desorbed as CO and the remaining oxygen and carbon began to incorporate. Also at this temperature sulfur began to diffuse out of the bulk to the surface and at approximately 800 C formed a complete monolayer. At 900 C, carbon and oxygen virtually disappeared, leaving the monolayer of sulfur as the only surface contaminant. The hydrogen diffusivity was found to follow closely the equation D = 7.01 x 10 to the -7th exp(-48.0/RT) sq m per second over the entire temperature range studied, thus indicating that hydrogen evolution is not significantly affected by the changing surface composition. The somewhat higher value of the diffusivity obtained in this work compared to past measurements in austenitic stainless steels may indicate the importance of sample preprocessing and ultrahigh vacuum conditions in minimizing the effects of surface layers.

  3. Investigating electrochemical removal of bacterial biofilms from stainless steel substrates.

    PubMed

    Dargahi, Mahdi; Hosseinidoust, Zeinab; Tufenkji, Nathalie; Omanovic, Sasha

    2014-05-01

    Electrochemical removal of biofilms deserves attention because of its ease of use and environmentally friendly nature. We investigated the influence of electrode potential and treatment time on the removal of a 10-day old Pseudomonas aeruginosa biofilm formed on stainless steel 316 L substrates. At electrode potentials more positive than -1.5 V vs. Ag/AgCl, lower removal rates were observed and only partial removal of the biofilm was achieved during a 1-min time interval. Electrostatic repulsion between the film and electrode surface is believed to drive biofilm detachment under these conditions. However, when the biofilm-coated substrates were treated at potentials negative of -1.5 V vs. Ag/AgCl, complete removal of a biofilm was achieved within seconds. Under these conditions, vigorous evolution of hydrogen gas is believed to be responsible for the film removal, mechanically detaching the bacteria and extracellular polymeric matrix from the substrate. Stainless steel substrates were also subjected to repeated cycles of biofilm formation and electrochemical removal. High removal efficiencies were maintained throughout this process suggesting the potential of the proposed technology for application on conductive surfaces in various industrial settings. PMID:24681392

  4. Deuterium retention in ITER-grade austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Nemanič, Vincenc; Žumer, Marko; Zajec, Bojan

    2008-11-01

    In view of the construction of ITER, it is essential to confirm that the retention of tritium by the large interior surface area of stainless steel will not become an issue for safety or operating inventory reasons. Retention of deuterium in ITER-grade austenitic stainless steel samples was studied during t = 24 h exposures to pure gaseous deuterium at p = 0.01 mbar and 0.1 mbar and T = 100 °C, 250 °C and 400 °C, respectively. The required high sensitivity for distinguishing hydrogen isotopes involved in the process (H2, HD and D2) was gained after suppression of the native hydrogen concentration by a thermal treatment at T = 400 °C for t = 200 h. The quantity of retained deuterium was determined by measuring the absolute pressure change during the deuterium exposure and subsequent mass spectrometry revealing an intense isotope exchange reaction. The retained amount of 2.6 × 1016 D cm-2 was the highest at T = 400 °C and p = 0.1 mbar and noticeably less at lower deuterium pressure and temperature. Our results, when compared with similar tritium exposures, do not exceed the limits set in the generic safety analysis for the ITER. They manifest that an extremely high sensitivity for deuterium absorption and release can be gained with a precise pressure measuring technique, otherwise attributed exclusively to tritium scintillation methods.

  5. Localized weld metal corrosion in stainless steel water tanks

    SciTech Connect

    Strum, M.J.

    1995-05-25

    The rapidly developed leaks within the TFC and TFD tanks (LLNL groundwater treatment facilities) were caused by localized corrosion within the resolidified weld metal. The corrosion was initiated by the severe oxidation of the backsides of the welds which left the exposed surfaces in a condition highly susceptible to aqueous corrosion. The propagation of surface corrosion through the thickness of the welds occurred by localized corrosive attack. This localized attack was promoted by the presence of shielded aqueous environments provided by crevices at the root of the partial penetration welds. In addition to rapid corrosion of oxidized surfaces, calcium carbonate precipitation provided an additional source of physical shielding from the bulk tank environment. Qualification testing of alternate weld procedures showed that corrosion damage can be prevented in 304L stainless steel GTA welds by welding from both sides while preventing oxidation of the tank interior through the use of an inert backing gas such as argon. Corrosion resistance was also satisfactory in GMA welds in which oxidized surfaces were postweld cleaned by wire brushing and chemically passivated in nitric acid. Further improvements in corrosion resistance are expected from a Mo-containing grade of stainless steel such as type 316L, although test results were similar for type 304L sheet welded with type 308L filler metal and type 316L sheet welded with type 316L filler metal.

  6. Abnormal grain growth in AISI 304L stainless steel

    SciTech Connect

    Shirdel, M.; Mirzadeh, H.; Parsa, M.H.

    2014-11-15

    The microstructural evolution during abnormal grain growth (secondary recrystallization) in 304L stainless steel was studied in a wide range of annealing temperatures and times. At relatively low temperatures, the grain growth mode was identified as normal. However, at homologous temperatures between 0.65 (850 °C) and 0.7 (900 °C), the observed transition in grain growth mode from normal to abnormal, which was also evident from the bimodality in grain size distribution histograms, was detected to be caused by the dissolution/coarsening of carbides. The microstructural features such as dispersed carbides were characterized by optical metallography, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, and microhardness. Continued annealing to a long time led to the completion of secondary recrystallization and the subsequent reappearance of normal growth mode. Another instance of abnormal grain growth was observed at homologous temperatures higher than 0.8, which may be attributed to the grain boundary faceting/defaceting phenomenon. It was also found that when the size of abnormal grains reached a critical value, their size will not change too much and the grain growth behavior becomes practically stagnant. - Highlights: • Abnormal grain growth (secondary recrystallization) in AISI 304L stainless steel • Exaggerated grain growth due to dissolution/coarsening of carbides • The enrichment of carbide particles by titanium • Abnormal grain growth due to grain boundary faceting at very high temperatures • The stagnancy of abnormal grain growth by annealing beyond a critical time.

  7. Corrosion study of bare and coated stainless steel

    NASA Technical Reports Server (NTRS)

    Morrison, J. D.

    1972-01-01

    A program was conducted at Kennedy Space Center from February 1968 to February 1971 to evaluate the performance of austenitic stainless steel alloys used in fluid systems lines. For several years, there had been numerous failures of stainless steel hardware caused by pitting and stress corrosion cracking. Several alloys were evaluated for effectiveness of certain sacrificial-type protective coverings in preventing corrosion failures. Samples were tested in specially designed racks placed 91 meters (100 yards) above high-tide line at Cape Kennedy. It is concluded that: (1) unprotected tubing samples showed evidence of pitting initiation after 2 weeks; (2) although some alloys develop larger pits than others, it is probable that the actual pitting rate is independent of alloy type; (3) the deepest pitting occurred in the sheltered part of the samples; and (4) zinc-rich coatings and an aluminum-filled coating have afforded sacrificial protection against pitting for at least 28 months. It is believed that a much longer effective coating life can be expected.

  8. Characterization and Evaluation of Aged Chromium Nickel Niobium Stainless Steels

    NASA Astrophysics Data System (ADS)

    Dewar, Matthew

    20Cr-32Ni-1Nb stainless steel alloys are commonly used in hydrogen reformer manifolds for transporting hot hydrogen by-products at 750-950°C. After long periods of exposure, embrittling secondary carbides and intermetallic phases can precipitate at the grain boundaries which can drastically reduce the ductility, and the repair weldability of the alloy. The intermetallic silicide, G-phase, is commonly observed in 20Cr-32Ni-1Nb stainless steels, and is prone to liquation cracking during welding operations. G-phase is deleterious to the material, where a high degree of G-phase coarsening will render the material unweldable. The present work will investigate various methods in mitigating G-phase precipitation. Variations in casting methods, wall thickness, homogenization treatments, and alloy chemistry will be examined by evaluating their microstructure after periodically aging the samples. Thermodynamic equilibrium modeling using computational thermodynamic tools will be used to optimize the 20Cr-32Ni-1Nb chemistry following ASTM specifications.

  9. Characterization of particle exposure in ferrochromium and stainless steel production.

    PubMed

    Järvelä, Merja; Huvinen, Markku; Viitanen, Anna-Kaisa; Kanerva, Tomi; Vanhala, Esa; Uitti, Jukka; Koivisto, Antti J; Junttila, Sakari; Luukkonen, Ritva; Tuomi, Timo

    2016-07-01

    This study describes workers' exposure to fine and ultrafine particles in the production chain of ferrochromium and stainless steel during sintering, ferrochromium smelting, stainless steel melting, and hot and cold rolling operations. Workers' personal exposure to inhalable dust was assessed using IOM sampler with a cellulose acetate filter (AAWP, diameter 25 mm; Millipore, Bedford, MA). Filter sampling methods were used to measure particle mass concentrations in fixed locations. Particle number concentrations and size distributions were examined using an SMPS+C sequential mobile particle sizer and counter (series 5.400, Grimm Aerosol Technik, Ainring, Germany), and a hand-held condensation particle counter (CPC, model 3007, TSI Incorporated, MN). The structure and elemental composition of particles were analyzed using TEM-EDXA (TEM: JEM-1220, JEOL, Tokyo, Japan; EDXA: Noran System Six, Thermo Fisher Scientific Inc., Madison,WI). Workers' personal exposure to inhalable dust averaged 1.87, 1.40, 2.34, 0.30, and 0.17 mg m(-3) in sintering plant, ferrochromium smelter, stainless steel melting shop, hot rolling mill, and the cold rolling mill, respectively. Particle number concentrations measured using SMPS+C varied from 58 × 10(3) to 662 × 10(3) cm(-3) in the production areas, whereas concentrations measured using SMPS+C and CPC3007 in control rooms ranged from 24 × 10(3) to 243 × 10(3) cm(-3) and 5.1 × 10(3) to 97 × 10(3) cm(-3), respectively. The elemental composition and the structure of particles in different production phases varied. In the cold-rolling mill non-process particles were abundant. In other sites, chromium and iron originating from ore and recycled steel scrap were the most common elements in the particles studied. Particle mass concentrations were at the same level as that reported earlier. However, particle number measurements showed a high amount of ultrafine particles, especially in sintering, alloy smelting and melting, and tapping

  10. A process model for the heat-affected zone microstructure evolution in duplex stainless steel weldments: Part I. the model

    NASA Astrophysics Data System (ADS)

    Hemmer, H.; Grong, Ø.

    1999-11-01

    The present investigation is concerned with modeling of the microstructure evolution in duplex stainless steels under thermal conditions applicable to welding. The important reactions that have been modeled are the dissolution of austenite during heating, subsequent grain growth in the delta ferrite regime, and finally, the decomposition of the delta ferrite to austenite during cooling. As a starting point, a differential formulation of the underlying diffusion problem is presented, based on the internal-state variable approach. These solutions are later manipulated and expressed in terms of the Scheil integral in the cases where the evolution equation is separable or can be made separable by a simple change of variables. The models have then been applied to describe the heat-affected zone microstructure evolution during both thick-plate and thin-plate welding of three commercial duplex stainless steel grades: 2205, 2304, and 2507. The results may conveniently be presented in the form of novel process diagrams, which display contours of constant delta ferrite grain size along with information about dissolution and reprecipitation of austenite for different combinations of weld input energy and peak temperature. These diagrams are well suited for quantitative readings and illustrate, in a condensed manner, the competition between the different variables that lead to structural changes during welding of duplex stainless steels.

  11. A process model for the heat-affected zone microstructure evolution in duplex stainless steel weldments: Part I. The model

    SciTech Connect

    Hemmer, H.; Grong, O.

    1999-11-01

    The present investigation is concerned with modeling of the microstructure evolution in duplex stainless steels under thermal conditions applicable to welding. The important reactions that have been modeled are the dissolution of austenite during heating, subsequent grain growth in the delta ferrite regime, and finally, the decomposition of the delta ferrite to austenite during cooling. As a starting point, a differential formulation of the underlying diffusion problem is presented, based on the internal-state variable approach. These solutions are later manipulated and expressed in terms of the Scheil integral in the cases where the evolution equation is separable or can be made separable by a simple change of variables. The models have then been applied to describe the heat-affected zone microstructure evolution during both thick-plate and thin-plate welding of three commercial duplex stainless steel grades: 2205, 2304, and 2507. The results may conveniently be presented in the form of novel process diagrams, which display contours of constant delta ferrite grain size along with information about dissolution and reprecipitation of austenite for different combinations of weld input energy and peak temperature. These diagrams are well suited for quantitative readings and illustrate, in a condensed manner, the competition between the different variables that lead to structural changes during welding of duplex stainless steels.

  12. Preparation of corrosion-resistant and conductive trivalent Cr-C coatings on 304 stainless steel for use as bipolar plates in proton exchange membrane fuel cells by electrodeposition

    NASA Astrophysics Data System (ADS)

    Wang, Hsiang-Cheng; Sheu, Hung-Hua; Lu, Chen-En; Hou, Kung-Hsu; Ger, Ming-Der

    2015-10-01

    In this study, Cr-C-coated bipolar plates are produced by electroplating on the SS304 plates with a machined flow channel. The resulting plates were tested using potentiodynamic and potentiostatic measurements in simulated PEMFC environments, which show that the bipolar plate coated with Cr-C exhibited good anticorrosion performance. The corrosive current density of the Cr-C coating formed for a plating time of 10 min for 10 h exhibits a low stable value of 1.51 × 10-10 A/cm2 during the potentiostatic test in a 0.5 M H2SO4 + 2 ppm HF solution at 70 °C with an air purge, indicating that the Cr-C coating plated for 10 min is stable in a cathode environment. The interfacial contact resistance (ICR) of the bipolar plate with the Cr-C coating clearly improved, presenting an ICR of 19.52 mΩ cm2 at a pressure of 138 N/cm2. The results from scanning electron microscopy (SEM) and ICR before and after the corrosion tests indicate that the bipolar plate with the Cr-C coating is electrochemically stable. In this study, the maximum power density (212.41 mW/cm2) is obtained at a cell temperature of 80 °C and a gas flow rate of 300 standard cubic centimeters per minute (sccm) when Cr-C coated SS304 bipolar plates were used.

  13. European developments in the application of structural austenitic and duplex stainless steels

    SciTech Connect

    Cochrane, D.J.

    1995-12-31

    Stainless steel is increasingly being specified for structural applications. Principally, this is due to the aesthetic appeal of the material, no need for surface protection, durability, and the growing awareness, and use, of Life Cycle Cost analysis for assessing costs over the longer term, However, use of stainless steel in the U.K. offshore oil and gas platforms for fire and blast walls, has highlighted valuable properties of stainless steel that may be unfamiliar to structural designers. It is the purpose of this paper to demonstrate these properties. Additionally, new design guidance has become available in Europe as a result of a 4 year research program into the structural use of stainless steel. The ``Design Manual for Structural Stainless Steel`` was issued by Euro Inox and the Nickel Development Institute in 1994. This new manual will be outlined in this paper together with its influence on new European Building Standards and new European material standards for structural stainless steel. Currently in preparation, these include high strength grades with significantly higher strength than structural carbon steels. Finally, this paper will address the use of stainless steel for the reinforcement of concrete structures.

  14. Studies on Stress Corrosion Cracking of Super 304H Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Prabha, B.; Sundaramoorthy, P.; Suresh, S.; Manimozhi, S.; Ravishankar, B.

    2009-12-01

    Stress corrosion cracking (SCC) is a common mode of failure encountered in boiler components especially in austenitic stainless steel tubes at high temperature and in chloride-rich water environment. Recently, a new type of austenitic stainless steels called Super304H stainless steel, containing 3% copper is being adopted for super critical boiler applications. The SCC behavior of this Super 304H stainless steel has not been widely reported in the literature. Many researchers have studied the SCC behavior of steels as per various standards. Among them, the ASTM standard G36 has been widely used for evaluation of SCC behavior of stainless steels. In this present work, the SCC behavior of austenitic Fe-Cr-Mn-Cu-N stainless steel, subjected to chloride environments at varying strain conditions as per ASTM standard G36 has been studied. The environments employed boiling solution of 45 wt.% of MgCl2 at 155 °C, for various strain conditions. The study reveals that the crack width increases with increase in strain level in Super 304H stainless steels.

  15. VIEW OF STEEL PLATE DOOR IN NUCLEAR PHYSICS LABORATORY, BETWEEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF STEEL PLATE DOOR IN NUCLEAR PHYSICS LABORATORY, BETWEEN LABORATORY AND SP-SE REACTOR ROOM,LEVEL -15’, LOOKING NORTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

  16. Aerosol measurements from plasma torch cuts on stainless steel, carbon steel, and aluminum

    SciTech Connect

    Novick, V.J.; Brodrick, C.J.; Crawford, S.; Nasiatka, J.; Pierucci, K.; Reyes, V.; Sambrook, J.; Wrobel, S.; Yeary, J.

    1996-01-01

    The main purpose of this project is to quantify aerosol particle size and generation rates produced by a plasma torch whencutting stainless steel, carbon steel and aluminum. the plasma torch is a common cutting tool used in the dismantling of nuclear facilities. Eventually, other cutting tools will be characterized and the information will be compiled in a user guide to aid in theplanning of both D&D and other cutting operations. The data will be taken from controlled laboratory experiments on uncontaminated metals and field samples taken during D&D operations at ANL nuclear facilities. The plasma torch data was collected from laboratory cutting tests conducted inside of a closed, filtered chamber. The particle size distributions were determined by isokinetically sampling the exhaust duct using a cascade impactor. Cuts on different thicknesses showed there was no observable dependence of the aerosol quantity produced as a function of material thickness for carbon steel. However, data for both stainless steel and aluminum revealed that the aerosol mass produced for these materials appear to have some dependance on thickness, with thinner materials producing tmore aerosols. The results of the laboratory cutting tests show that most measured particle size distributions are bimodal with one mode at about 0.2 {mu}m and the other at about 10 {mu}m. The average Mass Median Aerodynamic Diameters (MMAD`s) for these tests are 0.36 {+-}0.08 {mu}m for stainless steel, 0.48 {+-}0.17{mu}m for aluminum and 0.52{+-}0.12 {mu}m for carbon steel.

  17. Adhesion and removal kinetics of Bacillus cereus biofilms on Ni-PTFE modified stainless steel.

    PubMed

    Huang, Kang; McLandsborough, Lynne A; Goddard, Julie M

    2016-01-01

    Biofilm control remains a challenge to food safety. A well-studied non-fouling coating involves codeposition of polytetrafluoroethylene (PTFE) during electroless plating. This coating has been reported to reduce foulant build-up during pasteurization, but opportunities remain in demonstrating its efficacy in inhibiting biofilm formation. Herein, the initial adhesion, biofilm formation, and removal kinetics of Bacillus cereus on Ni-PTFE-modified stainless steel (SS) are characterized. Coatings lowered the surface energy of SS and reduced biofilm formation by > 2 log CFU cm(-2). Characterization of the kinetics of biofilm removal during cleaning demonstrated improved cleanability on the Ni-PTFE coated steel. There was no evidence of biofilm after cleaning by either solution on the Ni-PTFE coated steel, whereas more than 3 log and 1 log CFU cm(-2) of bacteria remained on the native steel after cleaning with water and an alkaline cleaner, respectively. This work demonstrates the potential application of Ni-PTFE non-fouling coatings on SS to improve food safety by reducing biofilm formation and improving the cleaning efficiency of food processing equipment. PMID:27020838

  18. Atmospheric pitting corrosion of 304L stainless steel: the role of highly concentrated chloride solutions.

    PubMed

    Street, Steven R; Mi, Na; Cook, Angus J M C; Mohammed-Ali, Haval B; Guo, Liya; Rayment, Trevor; Davenport, Alison J

    2015-01-01

    The morphology of atmospheric pitting corrosion in 304L stainless steel plate was analysed using MgCl(2) droplets in relation to changes in relative humidity (RH) and chloride deposition density (CDD). It was found that highly reproducible morphologies occur that are distinct at different RH. Pitting at higher concentrations, i.e. lower RH, resulted in satellite pits forming around the perimeter of wide shallow dish regions. At higher RH, these satellite pits did not form and instead spiral attack into the shallow region was observed. Increasing CDD at saturation resulted in a very broad-mouthed pitting attack within the shallow dish region. Large data sets were used to find trends in pit size and morphology in what is essentially a heterogeneous alloy. Electrochemical experiments on 304 stainless steel wires in highly saturated solutions showed that the passive current density increased significantly above 3 M MgCl(2) and the breakdown pitting potential dropped as the concentration increased. It is proposed that the shallow dish regions grow via enhanced dissolution of the passive film, whereas satellite pits and a spiral attack take place with active dissolution of bare metal surfaces. PMID:25910020

  19. Passivation and anodic oxidation of duplex TiN coating on stainless steel

    SciTech Connect

    Rudenja, S.; Pan, J.; Wallinder, I.O.; Leygraf, C.; Kulu, P.

    1999-11-01

    The passivation and anodic oxidation of duplex TiN coatings deposited by arc ion plating onto prenitrided AISI 304 stainless steel have been studied by potentiodynamic polarization, electrochemical impedance spectroscopy, and Mott-Schottky measurements in 0.1 M H{sub 2}SO{sub 4} + 0.05 M HCl. The chemical composition of the oxidized surface film atop TiN was analyzed by X-ray photoelectron spectroscopy. Up to 1.2 V/SHE the TiN coating exhibits passive behavior, which is attributed to the formation of a TiO{sub 2}-like film of nanometer thickness which grows linearly with anodic potential at a rate of 2.4 nm/V. Above 1.2 V/SHE enhanced anodic oxidation of TiN is observed at a rate of 17.7 nm/V, and the overall corrosion performance is governed both by the oxidized TiN coating and by a metallic Ti interlayer atop the nitrided stainless steel substrate. At all potentials the TiO{sub 2} film is characterized by relatively high donor densities and is, furthermore, terminated by a hydroxylated surface.

  20. Removal of long-lived {sup 222}Rn daughters by electropolishing thin layers of stainless steel

    SciTech Connect

    Schnee, R. W.; Bowles, M. A.; Bunker, R.; McCabe, K.; White, J.; Cushman, P.; Pepin, M.; Guiseppe, V. E.

    2013-08-08

    Long-lived alpha and beta emitters in the {sup 222}Rn decay chain on detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay. Removal of tens of microns of material via electropolishing has been shown to be effective at removing radon daughters implanted into material surfaces. Some applications, however, require the removal of uniform and significantly smaller thicknesses. Here, we demonstrate that electropolishing < 1 μm from stainless-steel plates reduces the contamination efficiently, by a factor > 100. Examination of electropolished wires with a scanning electron microscope confirms that the thickness removed is reproducible and reasonably uniform. Together, these tests demonstrate the effectiveness of removal of radon daughters for a proposed low-radiation, multi-wire proportional chamber (the BetaCage), without compromising the screener’s energy resolution. More generally, electropolishing thin layers of stainless steel may effectively remove radon daughters without compromising precision-machined parts.