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Sample records for 9cr-1mo steel showed

  1. 9 Cr-- 1 Mo steel material for high temperature application

    SciTech Connect

    Jablonski, Paul D; Alman, David; Dogan, Omer; Holcomb, Gordon; Cowen, Christopher

    2012-11-27

    One or more embodiments relates to a high-temperature, titanium alloyed, 9 Cr-1 Mo steel exhibiting improved creep strength and oxidation resistance at service temperatures up to 650.degree. C. The 9 Cr-1 Mo steel has a tempered martensite microstructure and is comprised of both large (0.5-3 .mu.m) primary titanium carbides and small (5-50 nm) secondary titanium carbides in a ratio of. from about 1:1.5 to about 1.5:1. The 9 Cr-1 Mo steel may be fabricated using exemplary austenizing, rapid cooling, and tempering steps without subsequent hot working requirements. The 9 Cr-1 Mo steel exhibits improvements in total mass gain, yield strength, and time-to-rupture over ASTM P91 and ASTM P92 at the temperature and time conditions examined.

  2. Creep deformation mechanisms in modified 9Cr-1Mo steel

    NASA Astrophysics Data System (ADS)

    Shrestha, Triratna; Basirat, Mehdi; Charit, Indrajit; Potirniche, Gabriel P.; Rink, Karl K.; Sahaym, Uttara

    2012-04-01

    Modified 9Cr-1Mo (Grade 91) steel is currently considered as a candidate material for reactor pressure vessels (RPVs) and reactor internals for the Very High Temperature Reactor (VHTR). The tensile creep behavior of modified 9Cr-1Mo steel (Grade 91) was studied in the temperature range of 873-1023 K and stresses between 35 MPa and 350 MPa. Analysis of creep results yielded stress exponents of ∼9-11 in the higher stress regime and ∼1 in the lower stress regime. The high stress exponent in the power-law creep regime was rationalized by invoking the concept of threshold stress, which represents the lattice diffusion controlled dislocation climb process. Without threshold stress compensation, the activation energy was 510 ± 51 kJ/mol, while after correcting for the threshold stress, the activation energy decreased to 225 ± 24 kJ/mol. This value is close to the activation energy for lattice self-diffusion in α-Fe. Threshold stress calculations were performed for the high stress regime at all test temperatures. The calculated threshold stress showed a strong dependence on temperature. The creep behavior of Grade 91 steel was described by the modified Bird-Mukherjee-Dorn relation. The rate controlling creep deformation mechanism in the high stress regime was identified as the edge dislocation climb with a stress exponent of n = 5. On the other hand, the deformation mechanism in the Newtonian viscous creep regime (n = 1) was identified as the Nabarro-Herring creep.

  3. Probing Pulsed Current Gas Metal Arc Welding for Modified 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Krishnan, S.; Kulkarni, D. V.; De, A.

    2015-04-01

    Modified 9Cr-1Mo steels are commonly welded using gas tungsten arc welding process for its superior control over the rate of heat input and vaporization loss of the key alloying elements although the rate electrode deposition remains restricted. Recent developments in pulsed current gas metal arc welding have significantly improved its ability to enhance the rate of electrode deposition with a controlled heat input rate while its application for welding of modified 9Cr-1Mo steels is scarce. The present work reports a detailed experimental study on the pulsed current gas metal arc welding of modified 9Cr-1Mo steels. The effect of the shielding gas, welding current, and speed on the weld bead profile, microstructure and mechanical properties are examined. The results show that the pulsed current gas metal arc welding with appropriate welding conditions can provide acceptable bead profile and mechanical properties in welds of modified 9Cr-1Mo steels.

  4. NEGLIGIBLE CREEP CONDITIONS FOR MOD 9 CR 1 MO STEEL

    SciTech Connect

    Ren, Weiju; Riou, Bernard; Escaravage, Claude; Swindeman, Robert W; Cabrillat, Marie-Th�r�se; Allais, Lucien

    2006-01-01

    Mod 9 Cr 1 Mo Steel (grade 91) is one of the materials envisaged for the Reactor Pressure Vessel of Very High Temperature Reactors. To avoid the implementation of a surveillance program covering the monitoring of the creep damage throughout the whole life of the reactor, it is recommended to operate the Reactor Pressure Vessel in the negligible creep regime. In this paper, the background of negligible creep criteria available in nuclear Codes is first recalled and their limitations were analyzed. Then, guidance for deriving criteria more appropriate for mod 9 Cr 1 Mo steel is provided. Finally, R&D actions in the U. S. and France to support the new approaches are discussed and recommended.

  5. Characterization of modified 9 Cr-1 Mo steel extruded pipe

    SciTech Connect

    Sikka, V.K.; Hart, M.D.

    1985-04-01

    The fabrication of hot-extruded pipe of modified 9 Cr-1 Mo steel at Cameron Iron Works is described. The report also deals with the tempering response; tensile, Charpy impact, and creep properties; and microstructure of the hot-extruded pipe. The tensile properties of the pipe are compared with the average and average -1.65 standard error of estimate curves for various product forms of several commercial heats of this alloy. The creep-rupture properties are compared with the average curve for various product forms of the commercial heats.

  6. Characterization and Performance of Magnetron-Sputtered Zirconium Coatings Deposited on 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Singh, Akash; Murugesan, Somasundaram; Parameswaran, P.; Priya, R.; Thirumurugessan, R.; Muthukumar, N.; Mohandas, E.; Kamachi Mudali, U.; Krishnamurthi, J.

    2016-09-01

    Zirconium coatings of different thicknesses have been deposited at 773 K on 9Cr-1Mo steel substrate using pulsed DC magnetron sputtering. These coatings were heat treated in vacuum at two different temperatures (1173 and 1273 K) for one hour. X-ray diffraction (XRD) analysis of Zr-coated samples revealed the formation of α-phase (HCP structure) of Zr. XRD analysis of heat-treated samples show the presence of Zr3Fe and Zr2Fe intermetallics. The lattice parameter of these coatings was calculated, and it matches with the bulk values when the thickness reached 2µm. In order to understand this, crystallite size and strain values of these coatings were calculated from XRD plots employing Williamson-Hall method. In order to assess the performance of the coatings, systematic corrosion tests were carried out. The corrosion current density calculated from the polarization behavior showed that the corrosion current density of the uncoated 9Cr-1Mo steel was higher than the coated sample before and after the heat treatment. Studies using electrochemical impedance spectroscopy confirmed that the coated steel has higher impedance than the uncoated steel. The corrosion resistance of 9Cr1Mo steel had improved after Zr coating. However, the corrosion resistance of the coating after heat treatment decreased when compared to the as-deposited coating. The microstructure and composition of the surface oxide film influence the corrosion resistance of the Zr-coated 9Cr1Mo steel.

  7. Properties of modified 9Cr-1Mo cast steel

    SciTech Connect

    Zucco, J.A.; Canonico, D.A.

    1996-09-01

    This report describes the development and testing of a cast version of the popular ASME P-91 ferritic stainless steel. ASME and ASTM have approved its use in pressure vessels and boilers. The allowable strength level of the cast material is slightly lower than that of P- 91 wrought steel. The report also describes shop and field welding procedures developed for the cast steel. Figs, tabs.

  8. Sodium compatibility of HT-9 and Fe-9Cr-1Mo steels

    SciTech Connect

    Anantatmula, R.P.; Brehm, W.F.

    1985-11-01

    Ferritic steels have been receiving significant attention for possible use as steam generator tubing, and as alternate structural materials for liquid-metal heat-transport systems in commercial fast reactors, fusion reactors, etc. The materials are chosen on the basis of their high thermal conductivity, resistance to stress-corrosion-cracking in aqueous and steam environments, favorable fabricability and fairly low cost. These steels are available in several classes based on the microstructure and alloy content, viz., martensitics, bainitics, delta ferritics, and duplex steels. The low alloy bainitic steels (Fe-2-1/4Cr-1Mo) undergo extensive decarburization when exposed to high temperature flowing sodium. It is for this reason that ferritic steels with higher chromium (9 to 12% Cr) content have been proposed to minimize the carbon transfer and eventual degradation of mechanical properties. The martensitic steels, HT-9 and improved Fe9Cr1Mo are being considered as cladding/duct materials for liquid metal reactors (LMR). The alloy HT-9 is based on 12Cr1Mo composition. The improved Fe9Cr1Mo alloy is based on 9Cr1Mo composition as its name implies. The objective of the work reported here is to evaluate the sodium compatibility of the alloys at temperatures and flow rates typical of LMR cores. Testing was done for 8104 hours at 60/sup 0/C and 3992 hours at 650/sup 0/C.

  9. An experimental study of biaxial yield in modified 9Cr-1Mo steel at room temperature

    NASA Technical Reports Server (NTRS)

    Ellis, J. R.

    1985-01-01

    Described are two biaxial experiments which investigated yield, hardening, and flow behavior in modified 9Cr-1Mo steel at room temperature. The aim of these experiments was to determine whether the procedures recommended in NE Standard F9-5T for inelastic design analysis are applicable for this material in normalized and tempered condition. The first experiment investigated small offset yield behavior subsequent to radial preloads (sq rt of 3 sub sigma 12 = sub sigma 11) in tension-torsion stress space. The second experiment investigated yield behavior subsequent to nonradial preloads and also the time-dependent flow occurring during 0.5 hour periods at constant stress. The results of these experiments were qualitatively similar to those obtained earlier for types 304 and 316 stainless steel. Specifically, the von Mises yield criterion was found to provide a reasonable approximation of initial yield behavior. Although the subsequent yield surfaces suffered considerable distortion from their near-circular form after both radial and nonradial preloads, the hardening behavior was to the first order kinematic in nature. The strain-time data obtained during the 0.5 hr hold periods showed characteristics typical of creep curves. As in the case of earlier experiments, the high initial flow rates diminished more rapidly than would be estimated from elevated temperature data.

  10. Laser welding and post weld treatment of modified 9Cr-1MoVNb steel.

    SciTech Connect

    Xu, Z.

    2012-04-03

    Laser welding and post weld laser treatment of modified 9Cr-1MoVNb steels (Grade P91) were performed in this preliminary study to investigate the feasibility of using laser welding process as a potential alternative to arc welding methods for solving the Type IV cracking problem in P91 steel welds. The mechanical and metallurgical testing of the pulsed Nd:YAG laser-welded samples shows the following conclusions: (1) both bead-on-plate and circumferential butt welds made by a pulsed Nd:YAG laser show good welds that are free of microcracks and porosity. The narrow heat affected zone has a homogeneous grain structure without conventional soft hardness zone where the Type IV cracking occurs in conventional arc welds. (2) The laser weld tests also show that the same laser welder has the potential to be used as a multi-function tool for weld surface remelting, glazing or post weld tempering to reduce the weld surface defects and to increase the cracking resistance and toughness of the welds. (3) The Vicker hardness of laser welds in the weld and heat affected zone was 420-500 HV with peak hardness in the HAZ compared to 240 HV of base metal. Post weld laser treatment was able to slightly reduce the peak hardness and smooth the hardness profile, but failed to bring the hardness down to below 300 HV due to insufficient time at temperature and too fast cooling rate after the time. Though optimal hardness of weld made by laser is to be determined for best weld strength, methods to achieve the post weld laser treatment temperature, time at the temperature and slow cooling rate need to be developed. (4) Mechanical testing of the laser weld and post weld laser treated samples need to be performed to evaluate the effects of laser post treatments such as surface remelting, glazing, re-hardening, or tempering on the strength of the welds.

  11. Heat treated 9 Cr-1 Mo steel material for high temperature application

    DOEpatents

    Jablonski, Paul D.; Alman, David; Dogan, Omer; Holcomb, Gordon; Cowen, Christopher

    2012-08-21

    The invention relates to a composition and heat treatment for a high-temperature, titanium alloyed, 9 Cr-1 Mo steel exhibiting improved creep strength and oxidation resistance at service temperatures up to 650.degree. C. The novel combination of composition and heat treatment produces a heat treated material containing both large primary titanium carbides and small secondary titanium carbides. The primary titanium carbides contribute to creep strength while the secondary titanium carbides act to maintain a higher level of chromium in the finished steel for increased oxidation resistance, and strengthen the steel by impeding the movement of dislocations through the crystal structure. The heat treated material provides improved performance at comparable cost to commonly used high-temperature steels such as ASTM P91 and ASTM P92, and requires heat treatment consisting solely of austenization, rapid cooling, tempering, and final cooling, avoiding the need for any hot-working in the austenite temperature range.

  12. Data requirements to model creep in 9Cr-1Mo-V steel

    NASA Technical Reports Server (NTRS)

    Swindeman, R. W.

    1988-01-01

    Models for creep behavior are helpful in predicting response of components experiencing stress redistributions due to cyclic loads, and often the analyst would like information that correlates strain rate with history assuming simple hardening rules such as those based on time or strain. On the one hand, much progress has been made in the development of unified constitutive equations that include both hardening and softening through the introduction of state variables whose evolutions are history dependent. Although it is difficult to estimate specific data requirements for general application, there are several simple measurements that can be made in the course of creep testing and results reported in data bases. The issue is whether or not such data could be helpful in developing unified equations, and, if so, how should such data be reported. Data produced on a martensitic 9Cr-1Mo-V-Nb steel were examined with these issues in mind.

  13. The influence of thermal aging on the microstructure and fatigue properties of modified 9Cr-1Mo steel

    SciTech Connect

    Gieseke, B.G.; Brinkman, C.R.; Maziasz, P.J.

    1992-12-31

    Results of elevated-temperature low cycle fatigue and creep-fatigue tests are for one heat of modified 9Cr-1Mo steel in the normalized and tempered condition, after pre-aging 50,000 h at 538 and 593C, and after pre-aging for 75,000 h at 538C. These data show that pre-aging reduces the low cycle fatigue and creepfatigue lives in comparison to unaged material. The magnitude of these reductions are discussed along with the impact of pre-aging on the creep-fatigue damage diagrams. The effect of environment on creep-fatigue life of unaged modified 9Cr-1Mo steels is also addressed. Transmission electron microscopy explains changes in mechanical properties due to thermal aging. In the unaged alloy, TEM shows that dynamic recovery/recrystallization is occurring after significant strain-induced dislocation hardening around a stationary and stable array of as-tempered carbides during creep-fatigue. In contrast creep-fatigue testing of the pre-aged alloy produced a much coarser cellular subgrain structure and dislocation recovery without recrystallization. Aging causes as-tempered carbide dissolution and/or reprecipitation together with additional precipitation of Laves (Fe{sub 2}Mo) phase, which removes some of the precipitate-strengthening effects, and depletes solid-solution hardening effects on the dislocation networks and subgrain boundary structures.

  14. Modification in the Microstructure of Mod. 9Cr-1Mo Ferritic Martensitic Steel Exposed to Sodium

    NASA Astrophysics Data System (ADS)

    Prasanthi, T. N.; Sudha, Cheruvathur; Paul, V. Thomas; Bharasi, N. Sivai; Saroja, S.; Vijayalakshmi, M.

    2014-09-01

    Mod. 9Cr-1Mo is used as the structural material in the steam generator circuit of liquid metal-cooled fast breeder reactors. Microstructural modifications on the surface of this steel are investigated after exposing to flowing sodium at a temperature of 798 K (525 °C) for 16000 hours. Sodium exposure results in the carburization of the ferritic steel up to a depth of ~218 µm from the surface. Electron microprobe analysis revealed the existence of two separate zones with appreciable difference in microchemistry within the carburized layer. Differences in the type, morphology, volume fraction, and microchemistry of the carbides present in the two zones are investigated using analytical transmission electron microscopy. Formation of separate zones within the carburized layer is understood as a combined effect of leaching, diffusion of the alloying elements, and thermal aging. Chromium concentration on the surface in the α-phase suggested possible degradation in the corrosion resistance of the steel. Further, concentration-dependent diffusivities for carbon are determined in the base material and carburized zones using Hall's and den Broeder's methods, respectively. These are given as inputs for simulating the concentration profiles for carbon using numerical computation technique based on finite difference method. Predicted thickness of the carburized zone agrees reasonably well with that of experiment.

  15. Microstructure and elevated-temperature erosion-oxidation behaviour of aluminized 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Huttunen-Saarivirta, E.; Honkanen, M.; Tsipas, S. A.; Omar, H.; Tsipas, D.

    2012-10-01

    Degradation of materials by a combination of erosive wear and atmospheric oxidation at elevated temperatures constitutes a problem in some power generation processes, such as fluidized-bed combustion. In this work, 9Cr-1Mo steel, a common tube material in combustion chambers, is coated by a pack cementation method from an Al-containing pack in order to improve the resistance to erosion-oxidation at elevated temperatures. The resulting coating is studied in terms of microstructure and microhardness and tested for its resistance against impacts by sand particles in air at temperatures of 550-700 °C under several conditions, with thickness changes and appearance of the exposed surfaces being studied. The coating was found to contain several phases and layers, the outermost of which was essentially Al-rich and contained e.g., small AlN precipitates. The microhardness values for such coating ranged from 950 to 1100 HV20g. The coating provided the substrate with increased protection particularly against normal particle impacts, as manifested by smaller thickness losses for coated specimens as compared to uncoated counterparts. However, much of the coating was lost under all test conditions, despite the fact that particle debris formed a homogeneous layer on the surface. These results are described and discussed in this paper.

  16. Transfer of modified 9Cr-1Mo steel technology through cooperative programs (1980-1985)

    SciTech Connect

    Sikka, V.K.; DiStefano, J.R.; Patriarca, P.

    1986-06-01

    The principal objective of the United States Department of Energy (DOE) 9Cr-1Mo steel development program has been to provide the data and analyses required by designers for use of the alloy in advanced liquid metal reactors to reduce technical tasks and plant capital costs. It was recognized early that designers would not consider use of any material for nuclear applications unless there was a considerable body of experience already established. Toward this end, the plan has been to get the alloy accepted in Section I (Power Boilers), Section II (Materials Specifications), Section VIII (Pressure Vessels), and Section III (Nuclear power Plant Components) of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV) Code as logical steps in the process. To achieve this objective, extensive interaction with the industrial community was considered mandatory. Accordingly, an intensive effort to achieve technology transfer was initiated, which resulted in the involvement of many organizations. This report is a compilation of 47 status sheets describing 35 participating organizations and funding sources, purpose of the interactions, material and product forms utilized, summary of the work completed, findings, and appropriate references. These interactions contributed significantly toward the fulfillment of the program goals.

  17. Effect of Alloy 625 Buffer Layer on Hardfacing of Modified 9Cr-1Mo Steel Using Nickel Base Hardfacing Alloy

    NASA Astrophysics Data System (ADS)

    Chakraborty, Gopa; Das, C. R.; Albert, S. K.; Bhaduri, A. K.; Murugesan, S.; Dasgupta, Arup

    2016-04-01

    Dashpot piston, made up of modified 9Cr-1Mo steel, is a part of diverse safety rod used for safe shutdown of a nuclear reactor. This component was hardfaced using nickel base AWS ER NiCr-B alloy and extensive cracking was experienced during direct deposition of this alloy on dashpot piston. Cracking reduced considerably and the component was successfully hardfaced by application of Inconel 625 as buffer layer prior to hardface deposition. Hence, a separate study was undertaken to investigate the role of buffer layer in reducing the cracking and on the microstructure of the hardfaced deposit. Results indicate that in the direct deposition of hardfacing alloy on modified 9Cr-1Mo steel, both heat-affected zone (HAZ) formed and the deposit layer are hard making the thickness of the hard layer formed equal to combined thickness of both HAZ and deposit. This hard layer is unable to absorb thermal stresses resulting in the cracking of the deposit. By providing a buffer layer of Alloy 625 followed by a post-weld heat treatment, HAZ formed in the modified 9Cr-1Mo steel is effectively tempered, and HAZ formed during the subsequent deposition of the hardfacing alloy over the Alloy 625 buffer layer is almost completely confined to Alloy 625, which does not harden. This reduces the cracking susceptibility of the deposit. Further, unlike in the case of direct deposition on modified 9Cr-1Mo steel, dilution of the deposit by Ni-base buffer layer does not alter the hardness of the deposit and desired hardness on the deposit surface could be achieved even with lower thickness of the deposit. This gives an option for reducing the recommended thickness of the deposit, which can also reduce the risk of cracking.

  18. Prediction and Monitoring Systems of Creep-Fracture Behavior of 9Cr-1Mo Steels for Teactor Pressure Vessels

    SciTech Connect

    Potirniche, Gabriel; Barlow, Fred D.; Charit, Indrajit; Rink, Karl

    2013-11-26

    A recent workshop on next-generation nuclear plant (NGNP) topics underscored the need for research studies on the creep fracture behavior of two materials under consideration for reactor pressure vessel (RPV) applications: 9Cr-1Mo and SA-5XX steels. This research project will provide a fundamental understanding of creep fracture behavior of modified 9Cr-1Mo steel welds for through modeling and experimentation and will recommend a design for an RPV structural health monitoring system. Following are the specific objectives of this research project: Characterize metallurgical degradation in welded modified 9Cr-1Mo steel resulting from aging processes and creep service conditions; Perform creep tests and characterize the mechanisms of creep fracture process; Quantify how the microstructure degradation controls the creep strength of welded steel specimens; Perform finite element (FE) simulations using polycrystal plasticity to understand how grain texture affects the creep fracture properties of welds; Develop a microstructure-based creep fracture model to estimate RPVs service life; Manufacture small, prototypic, cylindrical pressure vessels, subject them to degradation by aging, and measure their leak rates; Simulate damage evolution in creep specimens by FE analyses; Develop a model that correlates gas leak rates from welded pressure vessels with the amount of microstructural damage; Perform large-scale FE simulations with a realistic microstructure to evaluate RPV performance at elevated temperatures and creep strength; Develop a fracture model for the structural integrity of RPVs subjected to creep loads; and Develop a plan for a non-destructive structural health monitoring technique and damage detection device for RPVs.

  19. Effect of sodium environment on the low cycle fatigue properties of modified 9Cr-1Mo ferritic martensitic steel

    NASA Astrophysics Data System (ADS)

    Kannan, R.; Sandhya, R.; Ganesan, V.; Valsan, M.; Bhanu Sankara Rao, K.

    2009-02-01

    Modified 9Cr-1Mo ferritic steel is the material of current interest for the steam generator components of liquid metal cooled fast breeder reactors (LMFBRs). The steam generator has been designed to operate for 30-40 years. It is important to accurately determine the life of the components in the actual environment in order to consider the extension of life beyond the design life. With this objective in view, a programme has been initiated at our laboratory to evaluate the effects of flowing sodium on the LCF behaviour of modified 9Cr-1Mo steel. LCF tests conducted in flowing sodium environment at 823 K and 873 K exhibited cyclic softening behaviour both in air and sodium environments. The fatigue lives are significantly improved in sodium environment when compared to the data obtained in air environment under identical testing conditions. The lack of oxidation in sodium environment is considered to be responsible for the delayed crack initiation and consequent increase in fatigue life. Comparison of experimental lifetimes with RCC-MR design code predictions indicated that the design curve based on air tests is too conservative.

  20. The effect of long-term aging on the impact properties of modified 9Cr-1Mo steel

    SciTech Connect

    Alexander, D.J.; Maziasz, P.J.; Brinkman, C.R.

    1992-12-31

    The Charpy impact and room-temperature tensile properties of two heats of modified 9Cr-1Mo steel have been examined after aging at temperatures from 482 to 704C for times up to 75,000 h. In general, aging at lower temperatures (482, 538, or 593C) resulted in little change in the room-temperature tensile properties, but rapid increases in the transition temperature, with the greatest increase for an aging time of 25,000 h. The upper-shelf energy level decreased, reaching a minimum at 25,000 h, followed by recovery at 50,000-h aging. At higher aging temperatures (649 and 704C) there was little change in the transition temperatures, but significant softening at room temperature, and large increases in the upper-shelf energy.

  1. Effects of Simulated Microstructure on the Creep Rupture of the Modified 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Hsiao, T. H.; Chen, T. C.; Jeng, S. L.; Chung, T. J.; Tsay, L. W.

    2016-10-01

    Microstructures of the heat-affected zone (HAZ) of a Gr. 91 steel weld were simulated to evaluate their effects on the creep life of the weld at elevated temperatures. The Ac1 and Ac3 temperatures of the Gr. 91 steel were determined by a dilatometer to be at 867 and 907 °C, respectively. An infrared heating system was employed to heat the samples to 860 (STOT), 900 (ICHAZ) and 940 °C (FGHAZ) for 1 min, followed by cooling to room temperature. The simulated specimens were then subjected to conventional post-weld heat treatment (PWHT) at 750 °C/2 h. After the PWHT, the tempered ICHAZ specimen had a shortest creep life among the specimens tested at 650 °C/60 MPa. Moreover, the simulated specimen heated to 860 °C (STOT) was more likely to fracture at 615 °C/80 MPa than others.

  2. Effects of Simulated Microstructure on the Creep Rupture of the Modified 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Hsiao, T. H.; Chen, T. C.; Jeng, S. L.; Chung, T. J.; Tsay, L. W.

    2016-08-01

    Microstructures of the heat-affected zone (HAZ) of a Gr. 91 steel weld were simulated to evaluate their effects on the creep life of the weld at elevated temperatures. The Ac1 and Ac3 temperatures of the Gr. 91 steel were determined by a dilatometer to be at 867 and 907 °C, respectively. An infrared heating system was employed to heat the samples to 860 (STOT), 900 (ICHAZ) and 940 °C (FGHAZ) for 1 min, followed by cooling to room temperature. The simulated specimens were then subjected to conventional post-weld heat treatment (PWHT) at 750 °C/2 h. After the PWHT, the tempered ICHAZ specimen had a shortest creep life among the specimens tested at 650 °C/60 MPa. Moreover, the simulated specimen heated to 860 °C (STOT) was more likely to fracture at 615 °C/80 MPa than others.

  3. In Situ Tensile Deformation and Residual Stress Measurement by Neutron Diffraction in Modified 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Shrestha, Triratna; Charit, Indrajit; Potirniche, Gabriel

    2015-12-01

    The deformation behavior of monolithic modified 9Cr-1Mo (Grade 91) steel during uniaxial tensile loading was studied using the in situ neutron diffraction technique. The residual stress distribution across gas tungsten arc welds in the Grade 91 steel was measured by the time-of-flight neutron diffraction method using the SMARTS diffractometer at Lujan Neutron Scattering Center, Los Alamos National Laboratory. Grade 91 plates were welded using the gas tungsten arc welding (GTAW) technique. The load sharing by different grain orientations was observed during the tensile loading. The residual stresses along three orthogonal directions were determined at the mid-thickness, 4.35 and 2.35 mm below the surface of both the as-welded and post-weld heat-treated plates. The residual stresses of the as-welded plates were compared with those of the post-weld heat-treated plates. The post-weld heat treatment significantly reduced the residual stress level in the base metal, the heat-affected zone, and the weld zone. Vickers microhardness across the weld zone of the as-welded and post-weld heat-treated specimens was evaluated and correlated with the observed residual stress profile and microstructure.

  4. The morphology and ageing behaviour of δ-ferrite in a modified 9Cr-1Mo steel

    NASA Astrophysics Data System (ADS)

    Kishore, R.; Singh, R. N.; Sinha, T. K.; Kashyap, B. P.

    1992-10-01

    Dual phase (martensite + δ-ferrite) microstructures were developed in a modified 9Cr-1Mo steel, by austenitising at 1523-1623 K, followed by water-quenching. These duplex structures were thermally aged at 973 K for ageing periods varying from 30 min to 21 h. Morphological aspects of δ-ferrite phase and its response to age-hardening were studied by optical, scanning electron and transmission electron microscopy, X-ray diffraction, electron probe microanalysis and microhardness testing. It was observed that austenitizing at 1523 K produced fine, acicular δ-ferrite while the δ-ferrite formed by austenitising at higher temperatures (1573-1623 K) were massive, irregular-shaped and banded. Moreover the presence of 8-ferrite caused an abnormally strong (110) reflection, observed in X-ray diffraction patterns of martensite plus δ-ferrite structures. This behaviour is thought to be due to development of (110) texture in δ-ferrite phase. Thermal ageing at 973 K caused age-hardening of δ-ferrite with a peak hardness attained after 3.6 ks of ageing. Electron microscopic results suggest that the observed hardening was caused by the formation of Fe 2Mo Laves phase.

  5. Effect of Activated Flux on the Microstructure, Mechanical Properties, and Residual Stresses of Modified 9Cr-1Mo Steel Weld Joints

    NASA Astrophysics Data System (ADS)

    Maduraimuthu, V.; Vasudevan, M.; Muthupandi, V.; Bhaduri, A. K.; Jayakumar, T.

    2012-02-01

    A novel variant of tungsten inert gas (TIG) welding called activated-TIG (A-TIG) welding, which uses a thin layer of activated flux coating applied on the joint area prior to welding, is known to enhance the depth of penetration during autogenous TIG welding and overcomes the limitation associated with TIG welding of modified 9Cr-1Mo steels. Therefore, it is necessary to develop a specific activated flux for enhancing the depth of penetration during autogeneous TIG welding of modified 9Cr-1Mo steel. In the current work, activated flux composition is optimized to achieve 6 mm depth of penetration in single-pass TIG welding at minimum heat input possible. Then square butt weld joints are made for 6-mm-thick and 10-mm-thick plates using the optimized flux. The effect of flux on the microstructure, mechanical properties, and residual stresses of the A-TIG weld joint is studied by comparing it with that of the weld joints made by conventional multipass TIG welding process using matching filler wire. Welded microstructure in the A-TIG weld joint is coarser because of the higher peak temperature in A-TIG welding process compared with that of multipass TIG weld joint made by a conventional TIG welding process. Transverse strength properties of the modified 9Cr-1Mo steel weld produced by A-TIG welding exceeded the minimum specified strength values of the base materials. The average toughness values of A-TIG weld joints are lower compared with that of the base metal and multipass weld joints due to the presence of δ-ferrite and inclusions in the weld metal caused by the flux. Compressive residual stresses are observed in the fusion zone of A-TIG weld joint, whereas tensile residual stresses are observed in the multipass TIG weld joint.

  6. Heat treatment effects on impact toughness of 9Cr-1MoVNb and 12Cr-1MoVW steels irradiated to 100 dpa

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.

    1997-08-01

    Plates of 9Cr-1MoVNb and 12Cr-1MoVW steels were given four different heat treatments: two normalizing treatments were used and for each normalizing treatment two tempers were used. Miniature Charpy specimens from each heat treatment were irradiated to {approx}19.5 dpa at 365{degrees}C and to {approx}100 dpa at 420{degrees}C in the Fast Flux Test Facility (FFTF). In previous work, the same materials were irradiated to 4-5 dpa at 365{degrees}C and 35-36 dpa at 420{degrees}C in FFTF. The tests indicated that prior austenite grain size, which was varied by the different normalizing treatments, had a significant effect on impact behavior of the 9Cr-1MoVNb but not on the 12Cr-1MoVW. Tempering treatment had relatively little effect on the shift in DBTT for both steels. Conclusions are presented on how heat treatment can be used to optimize impact properties.

  7. Microstructural Analysis of Orientation-Dependent Recovery and Recrystallization in a Modified 9Cr-1Mo Steel Deformed by Compression at a High Strain Rate

    NASA Astrophysics Data System (ADS)

    Zhang, Zhenbo; Zhang, Yubin; Mishin, Oleg V.; Tao, Nairong; Pantleon, Wolfgang; Juul Jensen, Dorte

    2016-09-01

    The evolution of the microstructure and texture during annealing of a modified ferritic/martensitic 9Cr-1Mo steel compressed by dynamic plastic deformation (DPD) to a strain of 2.3 has been investigated using transmission electron microscopy and electron backscatter diffraction. It is found that the duplex <111> + <100> fiber texture formed by DPD is transformed during annealing to a dominant <111> fiber texture, and that crystallites of the <111> component have an advantage during both nucleation and growth. Detailed characterization of the microstructural morphology, and estimation of the stored energies in <111>- and <100>-oriented regions in deformed and annealed samples, as well as investigations of the growth of recrystallizing grains, are used to analyze the annealing behavior. It is concluded that recrystallization in the given material occurs by a combination of oriented nucleation and oriented growth.

  8. High-temperature mechanical properties improvement on modified 9Cr-1Mo martensitic steel through thermomechanical treatments

    NASA Astrophysics Data System (ADS)

    Hollner, S.; Fournier, B.; Le Pendu, J.; Cozzika, T.; Tournié, I.; Brachet, J.-C.; Pineau, A.

    2010-10-01

    In the framework of the development of generation IV nuclear reactors and fusion nuclear reactors, materials with an improved high temperature (≅650 °C) mechanical strength are required for specific components. The 9-12%Cr martensitic steels are candidate for these applications. Thermomechanical treatments including normalisation at elevated temperature (1150 °C), followed by warm-rolling in metastable austenitic phase and tempering, have been applied on the commercial Grade 91 martensitic steel in order to refine its microstructure and to improve its precipitation state. The temperature of the warm-rolling was set at 600 °C, and those of the tempering heat-treatment at 650 °C and 700 °C thanks to MatCalc software calculations. Microstructural observations proved that the warm-rolling and the following tempering heat-treatment lead to a finer martensitic microstructure pinned with numerous small carbide and nitride particles. The hardness values of thermomechanically treated Grade 91 steel are higher than those of the as-received Grade 91. It is also shown that the yield stress and the ductility of the thermomechanically treated Grade 91 steel are significantly improved compared to the as-received material. Preliminary creep results showed that these thermomechanical treatments improve the creep lifetime by at least a factor 14.

  9. Temperature dependence of liquid metal embrittlement susceptibility of a modified 9Cr-1Mo steel under low cycle fatigue in lead-bismuth eutectic at 160-450 °C

    NASA Astrophysics Data System (ADS)

    Gong, Xing; Marmy, Pierre; Qin, Ling; Verlinden, Bert; Wevers, Martine; Seefeldt, Marc

    2016-01-01

    Low cycle fatigue properties of a 9Cr-1Mo ferritic-martensitic steel (T91) have been tested in a low oxygen concentration (LOC) lead-bismuth eutectic (LBE) environment and in vacuum at 160-450 °C. The results show a clear fatigue endurance "trough" in LOC LBE, while no such a strong temperature dependence of the fatigue endurance is observed when the steel is tested in vacuum. The fractographic observations by means of scanning electron microscopy (SEM) show that ductile microdimples are prevalent on the fracture surfaces of the specimens tested in vacuum, whereas the fracture surfaces produced in LOC LBE at all the temperatures are characterized by quasi-cleavage. Interestingly, using electron backscatter diffraction (EBSD), martensitic laths close to the fatigue crack walls or to the fracture surfaces of the specimens tested in vacuum are found to have transformed into very fine equiaxed subgrains. Nevertheless, such microstructural modifications do not happen to the specimens tested in LOC LBE at 160-450 °C. These interesting microstructural distinctions indicate that liquid metal embrittlement (LME) is able to occur throughout the fatigue crack propagation phase in the full range of the temperatures investigated, i.e. LME is not very sensitive to temperature during the fatigue crack propagation.

  10. Investigation of a Modified 9Cr-1Mo (P91) Pipe Failure

    SciTech Connect

    Klueh, Ronald L; Shingledecker, John P

    2006-04-01

    A modified 9Cr-1Mo feedwater (condensate) line at an Eastman Chemical Company plant failed in January 2005. The line was in continuous service since start-up December 2001 until failure. The Plant Superintendent estimated there were three thermal cycles since start-up, although there may have been as many as 25 thermal cycles during commissioning. Normal operating temperature was 325 F (163 C) and pressure was 1762 psig. The line was steam traced with the tracing activated only when ambient outdoor temperature dropped to 40 F (5 C). A modified 9Cr-1Mo steel (P91) pipe failure in a feedwater line in a chemical plant was investigated. The failure occurred in the vicinity of an elbow produced with socket welds of the pipe to the elbow. Based on metallography and hardness measurements, it was concluded that failure occurred because of an improper post-weld heat treatment of the socket weldment.

  11. Characterization of the structural details of residual austenite in the weld metal of a 9Cr1MoNbV welded rotor

    NASA Astrophysics Data System (ADS)

    Liu, Xia; Ji, Hui-jun; Liu, Peng; Wang, Peng; Lu, Feng-gui; Gao, Yu-lai

    2014-06-01

    The existence of residual austenite in weld metal plays an important role in determining the properties and dimensional accuracy of welded rotors. An effective corrosive agent and the metallographic etching process were developed to clearly reveal the characteristics of residual austenite in the weld metal of a 9Cr1MoNbV welded rotor. Moreover, the details of the distribution, shape, length, length-to-width ratio, and the content of residual austenite were systematically characterized using the Image-Pro Plus image analysis software. The results revealed that the area fraction of residual austenite was approximately 6.3% in the observed weld seam; the average area, length, and length-to-width ratio of dispersed residual austenite were quantitatively evaluated to be (5.5 ± 0.1) μm2, (5.0 ± 0.1) μm, and (2.2 ± 0.1), respectively. The newly developed corrosive agent and etching method offer an appropriate approach to characterize residual austenite in the weld metal of welded rotors in detail.

  12. Comparison of the mechanical strength properties of several high-chromium ferritic steels

    SciTech Connect

    Booker, M.K.; Sikka, V.K.; Booker, B.L.P.

    1981-01-01

    A modified 9 Cr-1 Mo ferritic steel has been selected as an alternative material for breeder reactors. Different 9 Cr-1 Mo steels are already being used commercially in UK and USA and a 9 Cr-2 Mo steel (EM12) is being used commercially in France. The 12% Cr steel alloy HT9 is also often recommended for high-temperature service. Creep-rupture data for all six seels were analyzed to yield rupture life as a function of stress, temperature, and lot-to-lot variations. Yield and tensile strength data for the three 9 Cr-1 Mo materials were also examined. All results were compared with Type 304 stainless steel, and the tensile and creep properties of the modified and British 9 Cr-1 Mo materials were used to calculate allowable stress values S/sub 0/ per Section VIII, Division 1 and S/sub m/ per code Case N-47 to section III of the ASME Boiler and Pressure Vessel Code. these values were compared with code listings for American commercial 9 Cr-1 Mo steel, 2 1/4 Cr-1 Mo steel, and Type 304 stainless steel. The conclusion is made that the modified 9 Cr-1 Mo steel displays tensile and creep strengths superior to those of the other ferritic materials examined and is at least comparable to Type 304 stainless steel from room temperature to about 625/sup 0/C. 31 figures.

  13. Creep-fatigue modelling in structural steels using empirical and constitutive creep methods implemented in a strip-yield model

    NASA Astrophysics Data System (ADS)

    Andrews, Benjamin J.

    The phenomena of creep and fatigue have each been thoroughly studied. More recently, attempts have been made to predict the damage evolution in engineering materials due to combined creep and fatigue loading, but these formulations have been strictly empirical and have not been used successfully outside of a narrow set of conditions. This work proposes a new creep-fatigue crack growth model based on constitutive creep equations (adjusted to experimental data) and Paris law fatigue crack growth. Predictions from this model are compared to experimental data in two steels: modified 9Cr-1Mo steel and AISI 316L stainless steel. Modified 9Cr-1Mo steel is a high-strength steel used in the construction of pressure vessels and piping for nuclear and conventional power plants, especially for high temperature applications. Creep-fatigue and pure creep experimental data from the literature are compared to model predictions, and they show good agreement. Material constants for the constitutive creep model are obtained for AISI 316L stainless steel, an alloy steel widely used for temperature and corrosion resistance for such components as exhaust manifolds, furnace parts, heat exchangers and jet engine parts. Model predictions are compared to pure creep experimental data, with satisfactory results. Assumptions and constraints inherent in the implementation of the present model are examined. They include: spatial discretization, similitude, plane stress constraint and linear elasticity. It is shown that the implementation of the present model had a non-trivial impact on the model solutions in 316L stainless steel, especially the spatial discretization. Based on these studies, the following conclusions are drawn: 1. The constitutive creep model consistently performs better than the Nikbin, Smith and Webster (NSW) model for predicting creep and creep-fatigue crack extension. 2. Given a database of uniaxial creep test data, a constitutive material model such as the one developed for

  14. Neutron irradiation effects on the ductile-brittle transition of ferritic/martensitic steels

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.

    1997-08-01

    Ferritic/martensitic steels such as the conventional 9Cr-1MoVNb (Fe-9Cr-1Mo-0.25V-0.06Nb-0.1C) and 12Cr-1MoVW (Fe-12Cr-1Mo-0.25V-0.5W-0.5Ni-0.2C) steels have been considered potential structural materials for future fusion power plants. The major obstacle to their use is embrittlement caused by neutron irradiation. Observations on this irradiation embrittlement is reviewed. Below 425-450{degrees}C, neutron irradiation hardens the steels. Hardening reduces ductility, but the major effect is an increase in the ductile-brittle transition temperature (DBTT) and a decrease in the upper-shelf energy, as measured by a Charpy impact test. After irradiation, DBTT values can increase to well above room temperature, thus increasing the chances of brittle rather than ductile fracture.

  15. Effect of heat treatment on microstructure and hardness of Grade 91 steel

    DOE PAGES

    Shrestha, Triratna; Alsagabi, Sultan; Charit, Indrajit; Potirniche, Gabriel; Glazoff, Michael

    2015-01-21

    The modified 9Cr-1Mo steel (Grade 91) is a material of choice in fossil-fuel-fired power plants with increased efficiency, service life, and reduction in emission of greenhouse gases. It is also considered a prospective material for the Next Generation Nuclear Power Plant for application in reactor pressure vessels at temperatures up to 650°C. In this paper, heat treatment of the modified 9Cr-1Mo steel was studied by normalizing and tempering the steel at various temperatures and times, with the ultimate goal of improving its creep resistance and optimizing material hardness. The microstructural evolution of the heat treated steels was correlated with themore » differential scanning calorimetric results. Optical microscopy, scanning and transmission electron microscopy in conjunction with microhardness profiles and calorimetric plots were used to understand the evolution of microstructure including precipitate structures in modified 9Cr-1Mo steel and relate it to the mechanical behavior of the steel. Thermo-CalcTM calculations were used to support experimental work and provide guidance in terms of the precipitate stability and microstructural evolution. Furthermore, the carbon isopleth and temperature dependencies of the volume fraction of different precipitates were constructed. The predicted and experimentally observed results were found to be in good agreement.« less

  16. Effect of heat treatment on microstructure and hardness of Grade 91 steel

    SciTech Connect

    Shrestha, Triratna; Alsagabi, Sultan; Charit, Indrajit; Potirniche, Gabriel; Glazoff, Michael

    2015-01-21

    The modified 9Cr-1Mo steel (Grade 91) is a material of choice in fossil-fuel-fired power plants with increased efficiency, service life, and reduction in emission of greenhouse gases. It is also considered a prospective material for the Next Generation Nuclear Power Plant for application in reactor pressure vessels at temperatures up to 650°C. In this paper, heat treatment of the modified 9Cr-1Mo steel was studied by normalizing and tempering the steel at various temperatures and times, with the ultimate goal of improving its creep resistance and optimizing material hardness. The microstructural evolution of the heat treated steels was correlated with the differential scanning calorimetric results. Optical microscopy, scanning and transmission electron microscopy in conjunction with microhardness profiles and calorimetric plots were used to understand the evolution of microstructure including precipitate structures in modified 9Cr-1Mo steel and relate it to the mechanical behavior of the steel. Thermo-CalcTM calculations were used to support experimental work and provide guidance in terms of the precipitate stability and microstructural evolution. Furthermore, the carbon isopleth and temperature dependencies of the volume fraction of different precipitates were constructed. The predicted and experimentally observed results were found to be in good agreement.

  17. The weldability of low activation Cr-W steels

    NASA Astrophysics Data System (ADS)

    Wang, C. A.; Klueh, R. L.; Chin, B. A.

    1992-09-01

    A series of chromium-tungsten ferritic steels patterned on the chromium-molybdenum alloys, case 2 14 Cr-1Mo, 9Cr-1MoVNb and 12Cr-1MoVW, were tested for weldability. These steels are being developed as candidates for the first wall and blanket structure of fusion reactors. Use of these materials will minimize the long-term radioactive hazards associated with disposal after service. In these low activation alloys, long half-life elements (Mo and Nb), which become activated during irradiation, are replaced. Autogenous bead-on-plate welds were performed using the gas tungsten arc welding process. Experimental results showed that all welds were free of cracks. Sound welds were achieved in case 2 14 and 5% Cr-W low activation steels while loss of ductility was observed in 9 and 12% Cr-W steels. This results suggests that post-weld heat treatment is necessary to restore toughness to the 9-12% Cr-W steels.

  18. Fatigue behavior of irradiated helium-containing ferritic steels for fusion reactor applications*1

    NASA Astrophysics Data System (ADS)

    Grossbeck, M. L.; Vitek, J. M.; Liu, K. C.

    1986-11-01

    The martensitic alloys 12Cr-1MoVW and 9Cr-1MoVNb have been irradiated in the High Flux Isotope Reactor (HFIR) and subsequently tested in fatigue. In order to achieve helium levels characteristic of fusion reactors, the 12Cr-1MoVW was doped with 1 and 2% Ni, resulting in helium levels of 210 and 410 appm at damage levels of 25 dpa. The 9Cr-1MoVNb was irradiated to a damage level of 3 dpa and contained less than 5 appm He. Irradiations were carried out at 55°C and testing at 22°C. No significant changes were found in 9Cr-1MoVNb upon irradiation at this damage level, but effects that could possibly be attributed to helium were found in 12Cr-1MoVW. Levels of 210 and 410 appm He produced cyclic strengthening of 29 and 34% over unirradiated nickel-doped materials, respectively. This cyclic hardening, attributable largely to helium, resulted in degradation of the cyclic life. However, the fatigue life remained comparable to or better than unirradiated 20%-cold-worked 316 stainless steel.

  19. Toward Improving the Type IV Cracking Resistance in Cr-Mo Steel Weld Through Thermo-Mechanical Processing

    NASA Astrophysics Data System (ADS)

    Shassere, Benjamin A.; Yamamoto, Yukinori; Babu, Sudarsanam Suresh

    2016-05-01

    Detailed microstructure characterization of Grade 91 (Modified 9Cr-1Mo, ASTM A387) steel subjected to a thermo-mechanical treatment process was performed to rationalize the cross-weld creep properties. A series of thermo-mechanical processing in the austenite phase region, followed by isothermal aging at temperatures at 973 K to 1173 K (700 °C to 900 °C), was applied to the Grade 91 steel to promote precipitation kinetics of MX (M: Nb and V, X: C and N) in the austenite matrix. Detailed characterization of the base metals after standard tempering confirmed the presence of fine MX dispersion within the tempered martensitic microstructure in steels processed at/and above 1073 K (800 °C). Relatively low volume fraction of M23C6 precipitates was observed after processing at 1073 K (800 °C). The cross-weld creep strength after processing was increased with respect to the increase of MX dispersion, indicating that these MX precipitates maintained during weld thermal cycles in the fine-grained heat-affected zone region and thereby contribute to improved creep resistant of welds in comparison to the welds made with the standard "normalization and tempering" processes. The steels processed in this specific processing condition showed improved cross-weld creep resistance and sufficient room temperature toughness. The above data are also analyzed based on existing theories of creep deformation based on dislocation climb mechanism.

  20. Toward Improving the Type IV Cracking Resistance in Cr-Mo Steel Weld Through Thermo-Mechanical Processing

    DOE PAGES

    Shassere, Benjamin A.; Yamamoto, Yukinori; Babu, Sudarsanam Suresh

    2016-02-23

    Detailed microstructure characterization of Grade 91 (Modified 9Cr-1Mo, ASTM A387) steel subjected to a thermo-mechanical treatment (TMT) process was performed to rationalize the cross-weld creep properties. A series of thermo-mechanical processing in the austenite phase region, followed by isothermal aging at temperatures at 973 to 1173 K (700 to 900ºC) was applied to the Grade 91 steel to promote precipitation kinetics of MX (M: Nb and V, X: C and N) in the austenite matrix. Detailed characterization of the base metals after standard tempering confirmed the presence of fine MX dispersion within the tempered martensitic microstructure in steels processed at/andmore » above 1073 K (800 ºC). Relatively low volume fraction of M23C6 precipitates was observed after processing at 1073 K (800 ºC). The cross-weld creep strength after processing was increased with respect to the increase of MX dispersion, indicating that these MX precipitates maintained during weld thermal cycles in the fine grained heat affected zone (FGHAZ) region and thereby contribute to improved creep resistant of welds in comparison to the welds made with the standard “normalization and tempering” processes. Lastly, the steels processed in this specific processing condition showed improved cross-weld creep resistance and sufficient room-temperature toughness. The above data is also analysed based on existing theories of creep deformation based on dislocation climb mechanism.« less

  1. 20. DETAILED OBLIQUE VIEW SOUTHWEST FURNACE 2, SHOWING STEEL FRAME ...

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

    20. DETAILED OBLIQUE VIEW SOUTHWEST FURNACE 2, SHOWING STEEL FRAME BOXES FOR COUNTERWEIGHTS, AND FURNACE HEATING PIPES AT RIGHT. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  2. Structures and properties of rapidly solidified 9Cr-lMo steel

    NASA Astrophysics Data System (ADS)

    Megusar, J.; Lavernia, E.; Domalavage, P.; Harling, O. K.; Grant, N. J.

    1984-05-01

    Irradiation induced shifts of the DBTT and possible hydrogen embrittlement of ferritic steels are currently considered major problems for CTR applications. Rapid solidification and in particular liquid dynamic compaction (LDC) has been studied in developing 9Cr-1Mo steel as a candidate first wall material. Structural refinements such as reduction of segregation, fine grain size and fine size of second phase particles are retained in this process and this will have a favorable effect on fracture properties. LDC has also the potential of preparing first wall components directly from the melt and this would have an economic advantage over conventional ingot technology.

  3. The influence on hydrogen permeation through steel of surface oxide layers and their characterisation using nuclear reactions

    SciTech Connect

    Earwaker, L.G.; Cheetham, J.L.; Farr, J.P.G.; Ross, D.K.

    1981-04-01

    The rate of hydrogen permeation through metals is important in many technological applications, not least in the nuclear industry. Permeation measurements at elevated temperature, made under conditions likely to be found in industry, have shown that oxide layers which form on the surface of steels can sometimes reduce permeation drastically. Measurements have been made on a range of steels, including AISI 321, AISI 316L, Fecralloy and 9% Cr/1% Mo, at temperatures from 600/sup 0/C up to 1100/sup 0/C and the oxide layers produced have been investigated using a range of nuclear reactions. Oxygen content has been measured using the /sup 16/O(d,p) reaction and, in the case of Fecralloy, the thickness of Al/sub 2/O/sub 3/ measured using the /sup 27/Al(p,..gamma..) reaction. Rutherford backscattering of alpha particles has also been used to investigate the behaviour of the surface layers, particularly for those alloys containing additives. Results show that at the lower temperatures investigated the oxide layers are generally mixed, while at higher temperatures they are largely Cr/sub 2/O/sub 3/, or Al/sub 2/O/sub 3/ in the case of Fecralloy. The addition of small amounts of rare earth metals tends to stabilise the oxide and prevent cracking and spalling. This higher degree of stability is found to decrease hydrogen permeation by up to four orders of magnitude.

  4. Interior detail of south wall with shed roofs showing steel ...

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

    Interior detail of south wall with shed roofs showing steel structure, paint room on lower right, view facing west-southwest - U.S. Naval Base, Pearl Harbor, Boat Shop, Seventh Street near Avenue E, Pearl City, Honolulu County, HI

  5. Pool area showing steel trusses from mezzanine on west ...

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

    Pool area showing steel trusses from mezzanine on west - Fitzsimons General Hospital, Swimming Pool, Southeast corner of East Nineteenth Place (formerly East McAfee Avenue) & Wheeling Street (formerly South Van Valzah Street), Aurora, Adams County, CO

  6. 6. SUPERINTENDENT'S COTTAGE PORTION OF EAST WALL SHOWING TYPICAL STEEL ...

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

    6. SUPERINTENDENT'S COTTAGE PORTION OF EAST WALL SHOWING TYPICAL STEEL SASH CASEMENT WINDOW AND LOG VIGAS. - Tucson Plant Materials Center, Superintendent's Cottage, 3241 North Romero Road, Tucson, Pima County, AZ

  7. INTERIOR VIEW OF BASEMENT UNDER FURNACE NO. 2 SHOWING STEEL ...

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

    INTERIOR VIEW OF BASEMENT UNDER FURNACE NO. 2 SHOWING STEEL AND REFRACTORY BRICK SUPPORT SYSTEM. - Chambers-McKee Window Glass Company, Furnace No. 2, Clay Avenue Extension, Jeannette, Westmoreland County, PA

  8. View of Irving Flume Tunnel #1 showing the steel flume ...

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

    View of Irving Flume Tunnel #1 showing the steel flume with trestles leading into concrete tunnel. Looking south - Childs-Irving Hydroelectric Project, Irving System, Flume Tunnel No. 1, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  9. 14. DETAIL OF SECOND NORTH APPROACH SPAN, SHOWING STEEL PIERS ...

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

    14. DETAIL OF SECOND NORTH APPROACH SPAN, SHOWING STEEL PIERS AND CANTILEVERED CONCRETE PEDESTAL. VIEW TO SOUTH. - Navajo Bridge, Spanning Colorado River at U.S. Highway 89 Alternate, Page, Coconino County, AZ

  10. Interior of the mine observation tower building, showing the steel ...

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

    Interior of the mine observation tower building, showing the steel compass ring in the tower. View facing east - U.S. Naval Base, Pearl Harbor, Waipio Peninsula, Waipo Peninsula, Pearl City, Honolulu County, HI

  11. 8. VIEW OF NEW PUMP PLANT CONSTRUCTION WORK, SHOWING STEEL ...

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

    8. VIEW OF NEW PUMP PLANT CONSTRUCTION WORK, SHOWING STEEL MANIFOLD RUNNING BELOW GRADE, April 24, 1952 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

  12. 13. Interior, Hangar 1301, showing bottom of a truss, steel ...

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

    13. Interior, Hangar 1301, showing bottom of a truss, steel hinge point and expansion joint, and concrete buttress, looking north northwest - Dover Air Force Base, Hangar No. 1301, Dover, Kent County, DE

  13. INTERIOR OF SOUTH ENTRY AIRLOCK SHOWING STEEL DOORS OPENING TO ...

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

    INTERIOR OF SOUTH ENTRY AIRLOCK SHOWING STEEL DOORS OPENING TO OUTSIDE AND INTO MAIN EQUIPMENT ROOM, VIEW FACING SOUTHEAST. - Naval Air Station Barbers Point, Telephone Exchange, Coral Sea Road north of Bismarck Sea Road, Ewa, Honolulu County, HI

  14. BLDG 101, CENTRAL ENTRY/ PASSAGE SHOWING LEAD FLOOR, STEEL WALLS ...

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

    BLDG 101, CENTRAL ENTRY/ PASSAGE SHOWING LEAD FLOOR, STEEL WALLS AND ASBESTOS CEILING - Naval Magazine Lualualei, Headquarters Branch, Operational Storage Building, Fifteenth Street near Kolekole Road intersection, Pearl City, Honolulu County, HI

  15. Effect of transient thermal cycles in a supercritical water-cooled reactor on the microstructure and properties of ferritic martensitic steels

    NASA Astrophysics Data System (ADS)

    Totemeier, T. C.; Clark, D. E.

    2006-09-01

    Microstructural and mechanical property changes in modified 9Cr-1Mo and HCM12A ferritic-martensitic steels resulting from short-duration thermal transients that occur during loss of feedwater flow events in a supercritical water reactor (SCWR) were studied. Specimen blanks were exposed to reference transients with 810 and 840 °C maximum temperatures using a thermal cycle simulator, and the subsequent microstructure, hardness, and creep-rupture strength were evaluated. Exposure to five consecutive cycles at either temperature resulted in no significant changes - only very slight indications of overtempering. Subsequent study of a wider variety of transient conditions showed that significant ferrite-to-austenite transformation occurred during thermal transients whose maximum temperature exceeded 860 °C, or during transients with holds exceeding 10 s at 840 °C maximum temperature. The subsequent presence of untempered martensite in the microstructure, coupled with severe overtempering, resulted in an order of magnitude decrease in creep-rupture strength at 600 °C. The findings were consistent with measured Ac1 temperatures for the two steels and the dependence of Ac1 on heating rate.

  16. Embrittlement of Cr-Mo steels after low fluence irradiation in HFIR

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.

    1995-04-01

    The goal of this work is the determination of the possible effect of the simultaneous formation of helium and displacement damage during irradiation on the Charpy impact behavior. Subsize Charpy impact specimens of 9Cr-1MoVNb (modified 9Cr-1Mo) and 12Cr-1MoVW (Sandvik HT9) steels and 12Cr-1MoVW with 2%Ni (12Cr-1MOVW-2Ni) were irradiated in the High Flux Isotope Reactor (HFIR) at 300 and 400{degree}C to damage levels up to 2.5 dpa. The objective was to study the effect of the simultaneous formation of displacement damage and transmutation helium on impact toghness. Despite the low fluence relative to previous irradiations of these steels, significant increases in the ductile-brittle transition temperature (DBTT) occurred. The 12Cr-1MoVW-2Ni steel irradiated at 400{degree}C had the largest increase in DBTT and displayed indications of intergranular fracture. A mechanism is proposed to explain how helium can affect the fracture behaviour of this latter steel in the present tests, and how it affected all three steels in previous experiments, where the steels were irradiated to higher fluences.

  17. Section NN, showing steel roof trusses, mezzanine iron railing, first ...

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

    Section NN, showing steel roof trusses, mezzanine iron railing, first floor doors, etc. San Bernardino Valley Union Junior College, Library Building. Also includes steel truss roof plan and a small stress diagram of the truss. Howard E. Jones, Architect, San Bernardino, California. Sheet 8, job no. 315. Scales 1/2 inch to the foot (section), and 1/8 and 1/16 inch to the foot. No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  18. View northeast, wharfs A and B, showing steel lift tower, ...

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

    View northeast, wharfs A and B, showing steel lift tower, pier C, and wharf B slope to water - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  19. CONSTRUCTION PROGRESS PHOTO SHOWING EMPLACEMENT STEEL BEAMS FUEL STORAGE BUILDING ...

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

    CONSTRUCTION PROGRESS PHOTO SHOWING EMPLACEMENT STEEL BEAMS FUEL STORAGE BUILDING (CPP-603) LOOKING EAST. INL PHOTO NUMBER NRTS-51-1371. Unknown Photographer, 1/31/1951 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  20. South Fork Latrine, interior showing head with steel tank mounted ...

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

    South Fork Latrine, interior showing head with steel tank mounted to wall; view south - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  1. 4. VIEW SHOWING NORTHEAST ELEVATION WITH STEEL SASH AND STUCCO ...

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

    4. VIEW SHOWING NORTHEAST ELEVATION WITH STEEL SASH AND STUCCO WALL FINISH, LOOKING SOUTH; 1906-1910 ONE-STORY SHED ADDITION WITH ROOF MONITOR IS IN FOREGROUND LEFT - Massachusetts Mills, Cloth Room-Section 15, 95 Bridge Street, Lowell, Middlesex County, MA

  2. 20. VIEW OF STEEL ARCH, SHOWING UNDERSIDE OF BRIDGE DECK ...

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

    20. VIEW OF STEEL ARCH, SHOWING UNDERSIDE OF BRIDGE DECK AT EAST END, TYPICAL FLOOR BEAM DETAILS AND IRVING DECKING, X-BRACING AND PENETRATION OF ARCH LOWER CHORD THROUGH DECK, LOOKING NORTHWEST. GAS LINE IS CARRIED ON FLOOR BEAM OUTRIGGERS. NEW BRIDGE IS AT LEFT - Notre Dame Bridge, Spanning Merrimack River on Bridge Street, Manchester, Hillsborough County, NH

  3. Charpy impact toughness of martensitic steels irradiated in FFTF: Effect of heat treatment

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.; Alexander, D. J.

    Charpy tests were made on plates of 9Cr-1MoVNb and 12Cr-1MoVW steels given four different normalizing-and-tempering treatments. One-third-size Charpy specimens from each steel were irradiated to 7.4 - 8 (times) 10(sup 26) n/m(sup 2) (about 34 - 37 dpa) at 420 C in the Materials Open Test Assembly of the Fast Flux Test Facility. Specimens were also thermally aged to 20000 h at 400 C to determine the effect of aging during irradiation. Previous work on these steels irradiated to 4 - 5 dpa at 365 C in MOTA were reexamined in light of the new results. The tests indicated that prior austenite grain size, which was varied by different normalizing treatments, had an effect on impact behavior of the 9Cr-1MoVNb but not on the 12Cr-1MoVW. Tempering treatment had relatively little effect on the shift in DBTT for both steels. Conclusions are presented on how heat treatment can be used to optimize properties.

  4. Report on thermal aging effects on tensile properties of ferritic-martensitic steels.

    SciTech Connect

    Li, M.; Soppet, W.K.; Rink, D.L.; Listwan, J.T.; Natesan, K.

    2012-05-10

    This report provides an update on the evaluation of thermal-aging induced degradation of tensile properties of advanced ferritic-martensitic steels. The report is the first deliverable (level 3) in FY11 (M3A11AN04030103), under the Work Package A-11AN040301, 'Advanced Alloy Testing' performed by Argonne National Laboratory, as part of Advanced Structural Materials Program for the Advanced Reactor Concepts. This work package supports the advanced structural materials development by providing tensile data on aged alloys and a mechanistic model, validated by experiments, with a predictive capability on long-term performance. The scope of work is to evaluate the effect of thermal aging on the tensile properties of advanced alloys such as ferritic-martensitic steels, mod.9Cr-1Mo, NF616, and advanced austenitic stainless steel, HT-UPS. The aging experiments have been conducted over a temperature of 550-750 C for various time periods to simulate the microstructural changes in the alloys as a function of time at temperature. In addition, a mechanistic model based on thermodynamics and kinetics has been used to address the changes in microstructure of the alloys as a function of time and temperature, which is developed in the companion work package at ANL. The focus of this project is advanced alloy testing and understanding the effects of long-term thermal aging on the tensile properties. Advanced materials examined in this project include ferritic-martensitic steels mod.9Cr-1Mo and NF616, and austenitic steel, HT-UPS. The report summarizes the tensile testing results of thermally-aged mod.9Cr-1Mo, NF616 H1 and NF616 H2 ferritic-martensitic steels. NF616 H1 and NF616 H2 experienced different thermal-mechanical treatments before thermal aging experiments. NF616 H1 was normalized and tempered, and NF616 H2 was normalized and tempered and cold-rolled. By examining these two heats, we evaluated the effects of thermal-mechanical treatments on material microstructures and

  5. A study of steel alloys for potential use in CO2 sequestration

    SciTech Connect

    Tylczak, Joseph H.; Rawers, James C.; Blankenship, Daniel

    2005-01-01

    The effect of CO2 as a greenhouse gas, and the potential of global warming, has led to the study of sequestration of CO2 as a mineral carbonate. Some of the processes of mineral sequestration involve handing large tonnages of silicate minerals and reacting them with CO2. In this study the Albany Research Center evaluated the effects of wear and corrosion individually, and any possible synergetic effects resulting from a combination of wear and corrosion, on steel alloys that might be used in CO2 sequestration. By understanding the mechanism of slurry material loss, a better selection of erosion/corrosion resistant steel alloys can be chosen which in turn help plan construction costs. Four different conventional alloys were chosen. The alloys include AISI 1080 carbon steel, a 9Cr, 1 Mo steel, a 316 stainless steel, and a heat treatable 440C stainless steel. These materials covered a large range of alloy composition and cost. A variety of erosion and corrosion tests were used to evaluate the steels response to selected sequestration environments. The tests used included: (i) wear from dry Jet and HAET erosion tests, (ii) corrosion from immersion tests, and (iii) slurry erosion/corrosion tests. The slurry wear tests were conducted using a 270-μm silica abrasive in water and a solution (a mixture of sodium chloride, magnesium chloride, and sodium carbonate) saturated with CO2 at pH levels of 4.5 and 9.4. The results of these tests were compared with the results dry erosion and immersion corrosion tests. The results of the various tests were then used to evaluate the mechanism of material loss and determine is the presence of synergetic effects. The corrosion test showed little loss of material for all alloys. The erosion tests showed only a small difference between alloys. The slurry tests showed synergistic effect of combining erosion and corrosion resulted in a significant additional loss of material. It was further found both increasing the hardness and amounts of

  6. Evaluation of misindexing of EBSD patterns in a ferritic steel.

    PubMed

    Karthikeyan, T; Dash, M K; Saroja, S; Vijayalakshmi, M

    2013-01-01

    The systematic misindexing caused by pseudo-symmetry Kikuchi diffraction patterns in automated Electron Backscatter Diffraction analysis has been studied in a 9Cr-1Mo ferritic steel. Grains with its [1 1 1] directed towards detector centre were found to be prone to misindexing, and the solutions exhibit a relative orientation of ±30° and 60° about the common [1 1 1] axis (as compared to the true orientation). Fictitious boundaries were detected within such grains, which satisfy the Σ3 or Σ13b type coincidence site lattice boundary criteria. Misindexing rate was reduced with more than six detected bands, but 30° rotated solution was comparatively more persistent, as the additional bands of (3 1 0)-type exhibited a nearly good pattern match. Increase in detector collection angle to 0.96 sr or number of detected bands to nine were found to be beneficial in preventing the misindexing problem.

  7. Irradiation effects in ferritic steels

    NASA Astrophysics Data System (ADS)

    Lechtenberg, Thomas

    1985-08-01

    Since 1979 the Alloy Development for Irradiation Performance (ADIP) task funded by the US Department of Energy has been studying the 2-12Cr class of ferritic steels to establish the feasibility of using them in fusion reactor first wall/breeding blanket (FW/B) applications. The advantages of ferritic steels include superior swelling resistance, low thermal stresses compared to austenitic stainless steels, attractive mechanical properties up to 600°C. and service histories exceeding 100 000 h. These steels are commonly used in a range of microstructural conditions which include ferritic, martensitic. tempered martensitic, bainitic etc. Throughout this paper where the term "ferritic" is used it should be taken to mean any of these microstructures. The ADIP task is studying several candidate alloy systems including 12Cr-1MoWV (HT-9), modified 9Cr-1MoVNb, and dual-phased steels such as EM-12 and 2 {1}/{4}Cr-Mo. These materials are ferromagnetic (FM), body centered cubic (bcc), and contain chromium additions between 2 and 12 wt% and molybdenum additions usually below 2%. The perceived issues associated with the application of this class of steel to fusion reactors are the increase in the ductile-brittle transition temperature (DBTT) with neutron damage, the compatibility of these steels with liquid metals and solid breeding materials, and their weldability. The ferromagnetic character of these steels can also be important in reactor design. It is the purpose of this paper to review the current understanding of these bcc steels and the effects of irradiation. The major points of discussion will be irradiation-induced or -enhanced dimensional changes such as swelling and creep, mechanical properties such as tensile strength and various measurements of toughness, and activation by neutron interactions with structural materials.

  8. View south, wharf A, showing steel lift tower U.S. ...

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

    View south, wharf A, showing steel lift tower - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  9. 22. Detail at southwest corner, T18, showing steel studs and ...

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

    22. Detail at southwest corner, T-18, showing steel studs and ribs and corrugated metal cladding - Advance Base Depot Davisville, Building T-17, Ninth Street southeast of Davisville Road, Davisville, Washington County, RI

  10. 13. Detail of steel ribs of T18, showing connectin to ...

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

    13. Detail of steel ribs of T-18, showing connectin to concrete foundation wall - Advance Base Depot Davisville, Building T-17, Ninth Street southeast of Davisville Road, Davisville, Washington County, RI

  11. A&M. TAN607. Construction detail showing structural steel framework with reinforcing ...

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

    A&M. TAN-607. Construction detail showing structural steel framework with reinforcing steel in place prior to pouring concrete for biparting doors between hot shop and special equipment service (SES) room. Facing north. Hot shop to left, SES room to right. slot for north half of door shows at upper left of view. Date: May 21, 1954. INEEL negative no. 10548 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  12. Aluminide coatings on iron-chromium-molybdenum steel synthesized by pack cementation for power generation applications

    NASA Astrophysics Data System (ADS)

    Wang, Yongqing

    Aluminide coatings on ferritic/martensite Fe-9Cr-1Mo steel substrates for power generation applications were developed via a pack cementation process at both high temperatures (1050°C) and low temperatures (650 and 700°C). Thermodynamic analysis was first conducted using HSC 5.0 software to provide a guideline for the selection of a masteralloy and the amount of the activator in the pack. Equilibrium partial pressures of halide gaseous species were calculated for packs containing Cr-Al binary alloys with Al contents varying from 5wt%Al to pure Al at both 1050°C and 700°C (Except for 650°C, at which only pure Al masteralloy was used). The calculation was also made for packs containing Hf, HfO2 or HfCl4 for developing Hf-modified aluminide coatings. At 1050°C, both simple and Hf-modified aluminide coatings were synthesized using a Cr-25wt.%Al binary masteralloy with a noncontact pack arrangement. Oxidation testing in air + 10vol.% H2O at 700°C indicates that simple pack aluminide coatings exhibited similar oxidation behavior to the model coatings fabricated via chemical vapor deposition (CVD). For up to 4,600h, Hf-modified aluminide coatings showed an improved oxidation resistance to CVD coatings. Low temperature aluminide coatings were synthesized at temperatures of 650 and 700°C, below the tempering temperature of the ferritic/martensite steel substrate. Initial coating development showed that a continuous Fe 2Al5 coating layer was deposited at 650°C with pure Al masteralloy. However, the coating thickness was not uniform and cracks were observed in the coatings. Cr-25wt%Al and Cr-15wt.%Al binary alloys with reduced Al activities were used to reduce the tendency of forming the brittle, Al-rich Fe2Al5 phase. With Cr-25wt.%Al masteralloy at 700°C, the synthesized coating consisted of a thin layer of Fe2Al 5 and an underlying layer of FeAl. The masteralloy of Cr-15wt.%Al was then utilized to further reduce the Al activity, and FeAl coatings with improved

  13. Effect of Austenization Temperature on the Microstructure and Strength of 9% and 12% Cr Ferritic-Martensitic Steels

    SciTech Connect

    Terry C. Totemeier

    2004-10-01

    The effect of reduced-temperature austenization on the microstructure and strength of two ferritic-martensitic steels was studied. Prototypic 9% and 12% Cr steels, grade 91 (9Cr-1MoVNb) and type 422 stainless (12Cr-1MoVW), respectively, were austenized at 925°C and 1050°C and tempered at 760°C. The reduced austenization temperature was intended to simulate potential inadequate austenization during field construction of large structures and also the thermal cycle experienced in the Type IV region of weld heat affected zones (HAZ). The microstructure, tensile behavior, and creep strength were characterized for both steels treated at each condition. The reduced austenization temperature resulted in general coarsening of carbides in both steels and polygonization of the tempered martensite structure in type 422. For this steel, a marked reduction in microhardness was observed, while there was little change in microhardness for grade 91. Slight reductions in tensile strength were observed for both steels at room temperature and elevated temperatures of 450 and 550°C. The strength reduction was greater for type 422 than for grade 91. At 650°C the tensile strength reduction was minimal for both steels. Marked reductions in creep rupture lives were observed for both steels at 650°C; the reductions were less at 600°C and minimal at 550°C. Overall, the higher Cr content steel was observed to be more sensitive to variations in heat treatment conditions.

  14. 50. VIEW OF CRUSHER ADDITION FROM EAST. SHOWS 100TON STEEL ...

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

    50. VIEW OF CRUSHER ADDITION FROM EAST. SHOWS 100-TON STEEL UNOXIDIZED ORE BIN, STEPHENS-ADAMSON 15 TON/HR INCLINED BUCKET ELEVATOR, AND DUST COLLECTION BIN IN UPPER RIGHT QUADRANT. THE ROD MILL CIRCUIT STOOD IN FRONT OF THE BUCKET ELEVATOR AND BEHIND THE BAKER COOLER (LEFT CENTER). MILL SOLUTION TANKS WERE IN FRONT OF THE CRUSHED OXIDIZED ORE BIN (CENTER), AND THE MILL FLOOR WAS THE NEXT LEVEL DOWN (RIGHT). - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  15. PERFORMANCE IMPROVEMENT OF CREEP-RESISTANT FERRITIC STEEL WELDMENTS THROUGH THERMO-MECHANICAL TREATMENT AND ALLOY DESIGN

    SciTech Connect

    Yamamoto, Yukinori; Babu, Prof. Sudarsanam Suresh; Shassere, Benjamin; Yu, Xinghua

    2016-01-01

    Two different approaches have been proposed for improvement of cross-weld creep properties of the high temperature ferrous structural materials for fossil-fired energy applications. The traditional creep strength-enhanced ferritic (CSEF) steel weldments suffer from Type IV failures which occur at the fine-grained heat affected zone (FGHAZ). In order to minimize the premature failure at FGHAZ in the existing CSEF steels, such as modified 9Cr-1Mo ferritic-martensitic steels (Grade 91), a thermo-mechanical treatment consisting of aus-forging/rolling and subsequent aus-aging is proposed which promotes the formation of stable MX carbonitrides prior to martensitic transformation. Such MX remains undissolved during welding process, even in FGHAZ, which successfully improves the cross-weld creep properties. Another approach is to develop a new fully ferrtic, creep-resistant FeCrAl alloy which is essentially free from Type IV failure issues. Fe-30Cr-3Al base alloys with minor alloying additions were developed which achieved a combination of good oxidation/corrosion resistance and improved tensile and creep performance comparable or superior to Grade 92 steel.

  16. Estimation of martensite feature size in a low-carbon alloy steel by microtexture analysis of boundaries.

    PubMed

    Karthikeyan, T; Dash, Manmath Kumar; Saroja, S; Vijayalakshmi, M

    2015-01-01

    A methodology for classifying the hierarchy of martensite boundaries from the EBSD microtexture data of low-carbon steel is presented. Quaternion algebra has been used to calculate the ideal misorientation between product α variants for Kurdjumov-Sachs (KS) and its nearby orientation relationships, and arrive at the misorientation angle-axis set corresponding to packet (12 types), block (3 types) and sub-block boundaries. Analysis of proximity of experimental misorientation between data points from the theoretical misorientation set is found to be useful for identifying the different types of martensite boundaries. The optimal OR in the alloy system and the critical deviation threshold for identification of martensite boundaries could both be ascertained by invoking the 'Enhancement Factor' concept. The prior-γ grain boundaries, packet, block and sub-block boundaries could be identified reasonably well, and their average intercept lengths in a typical tempered martensite microstructure of 9Cr-1Mo-0.1C steel was estimated as 31 μm, 14 μm, 9 μm and 4 μm respectively.

  17. Estimation of martensite feature size in a low-carbon alloy steel by microtexture analysis of boundaries.

    PubMed

    Karthikeyan, T; Dash, Manmath Kumar; Saroja, S; Vijayalakshmi, M

    2015-01-01

    A methodology for classifying the hierarchy of martensite boundaries from the EBSD microtexture data of low-carbon steel is presented. Quaternion algebra has been used to calculate the ideal misorientation between product α variants for Kurdjumov-Sachs (KS) and its nearby orientation relationships, and arrive at the misorientation angle-axis set corresponding to packet (12 types), block (3 types) and sub-block boundaries. Analysis of proximity of experimental misorientation between data points from the theoretical misorientation set is found to be useful for identifying the different types of martensite boundaries. The optimal OR in the alloy system and the critical deviation threshold for identification of martensite boundaries could both be ascertained by invoking the 'Enhancement Factor' concept. The prior-γ grain boundaries, packet, block and sub-block boundaries could be identified reasonably well, and their average intercept lengths in a typical tempered martensite microstructure of 9Cr-1Mo-0.1C steel was estimated as 31 μm, 14 μm, 9 μm and 4 μm respectively. PMID:25464145

  18. Safe Use Limits for Advanced Ferritic Steels in Ultra-Supercritical Power Boilers.

    SciTech Connect

    Swindeman, RW

    2003-11-03

    In 2000, a Cooperative Research and Development Agreement (CRADA) was undertaken between the Oak Ridge National Laboratory (ORNL) and the Babcock & Wilcox Company to examine the databases for advanced ferritic steels and determine the safe limits for operation in supercritical steam power boilers. The materials of interest included the vanadium-modified 9-12% Cr steels with 1-2% Mo or W. The first task involved a review of pertinent information and the down-selection of a steel of special interest. The long-time database for 9Cr-1Mo-V steel was found to be most satisfactory for the examinations, and this steel was taken to be representative of the group. The second task involved the collection of aged and service exposed samples for metallurgical and mechanical testing. Here, aged samples to 75,000 hours, laboratory-tested samples to 83,000 hours, and service-exposed sample with up to 143,000 hours exposure were collected. The third task involved mechanical testing of exposed samples. Creep-rupture testing to long times was undertaken. Variable stress and temperature testing was included. Results were compared against the prediction of damage models. These models seemed to be adequate for life prediction. The fourth task involved the metallurgical examination of exposed specimens. Changes in microstructure were compared against published information on the evolution of microstructures in 9Cr-Mo-V steels and the results were found to be consistent with expectations. The fifth task involved a survey of steam and fireside corrosion. Data from the service-exposed tubing was examined, and a literature survey was undertaken as part of an activity in support of ultra-supercritical steam boiler technology. The corrosion study indicated some concerns about long-time fireside corrosion and suggested temperature limits were needed for corrosive coal ash conditions.

  19. Contact nanofatigue shows crack growth in amorphous calcium phosphate on Ti, Co-Cr and Stainless steel.

    PubMed

    Saber-Samandari, Saeed; Gross, Karlis A

    2013-03-01

    Fatigue testing of load-bearing coated implants is usually very time-consuming and so a new contact nanofatigue test using a nanoindenter has been evaluated. A cube corner indenter provided the fastest indication of failure, through crack formation, compared to a spherical indenter. Contact nanofatigue was performed on a sintered hydroxyapatite and then on amorphous calcium phosphate splats produced on titanium, stainless steel and Co-Cr surfaces, made either at room temperature or on 250°C preheated surfaces. Sintered hydroxyapatite showed continual plastic deformation, but this is not that apparent for splats on metal surfaces. Substrate preheating was found to induce cracking in splats, explained by greater thermal residual stresses. Endurance during contact nanofatigue, measured as time to crack formation, was the lowest for splats on titanium followed by Co-Cr and stainless steel. The splat on titanium showed both cracking and plastic deformation during testing. Good agreement has been reached with previous studies with cracking directed to the substrate without splat delamination. Contact nanofatigue with the nanoindenter easily and quickly identifies cracking events that previously required detection with acoustic emission, and shows good feasibility for mechanical testing of discs and splats produced by thermal spraying, spray forming, laser-ablation, aerosol jet and ink jet printing. PMID:23164945

  20. Type IV Creep Damage Behavior in Gr.91 Steel Welded Joints

    NASA Astrophysics Data System (ADS)

    Hongo, Hiromichi; Tabuchi, Masaaki; Watanabe, Takashi

    2012-04-01

    Modified 9Cr-1Mo steel (ASME Grade 91 steel) is used as a key structural material for boiler components in ultra-supercritical (USC) thermal power plants at approximately 873 K (600 °C). The creep strength of welded joints of this steel decreases as a result of Type IV creep cracking that forms in the heat-affected zone (HAZ) under long-term use at high temperatures. The current article aims to elucidate the damage processes and microstructural degradations that take place in the HAZ of these welded joints. Long-term creep tests for base metal, simulated HAZ, and welded joints were conducted at 823 K, 873 K, and 923 K (550 °C, 600 °C, and 650 °C). Furthermore, creep tests of thick welded joint specimens were interrupted at several time steps at 873 K (600 °C) and 90 MPa, after which the distribution and evolution of creep damage inside the plates were measured quantitatively. It was found that creep voids are initiated in the early stages (0.2 of life) of creep rupture life, which coalesce to form a crack at a later stage (0.8 of life). In a fine-grained HAZ, creep damage is concentrated chiefly in an area approximately 20 pct below the surface of the plate. The experimental creep damage distributions coincide closely with the computed results obtained by damage mechanics analysis using the creep properties of a simulated fine-grained HAZ. Both the concentration of creep strain and the high multiaxial stress conditions in the fine-grained HAZ influence the distribution of Type IV creep damage.

  1. Verification of Allowable Stresses In ASME Section III Subsection NH For Grade 91 Steel & Alloy 800H

    SciTech Connect

    R. W. Swindeman; M. J. Swindeman; B. W. Roberts; B. E. Thurgood; D. L. Marriott

    2007-11-30

    The database for the creep-rupture of 9Cr-1Mo-V (Grade 91) steel was collected and reviewed to determine if it met the needs for recommending time-dependent strength values, S{sub t}, for coverage in ASME Section III Subsection NH (ASME III-NH) to 650 C (1200 F) and 600,000 hours. The accumulated database included over 300 tests for 1% total strain, nearly 400 tests for tertiary creep, and nearly 1700 tests to rupture. Procedures for analyzing creep and rupture data for ASME III-NH were reviewed and compared to the procedures used to develop the current allowable stress values for Gr 91 for ASME II-D. The criteria in ASME III-NH for estimating S{sub t} included the average strength for 1% total strain for times to 600,000 hours, 80% of the minimum strength for tertiary creep for times to 600,000 hours, and 67% of the minimum rupture strength values for times to 600,000 hours. Time-temperature-stress parametric formulations were selected to correlate the data and make predictions of the long-time strength. It was found that the stress corresponding to 1% total strain and the initiation of tertiary creep were not the controlling criteria over the temperature-time range of concern. It was found that small adjustments to the current values in III-NH could be introduced but that the existing values were conservative and could be retained. The existing database was found to be adequate to extend the coverage to 600,000 hours for temperatures below 650 C (1200 F).

  2. Survey of the degradation modes of candidate materials for high-level radioactive waste disposal containers

    SciTech Connect

    Vinson, D.W.; Nutt, W.M.; Bullen, D.B.

    1995-06-01

    Oxidation and atmospheric corrosion data suggest that addition of Cr provides the greatest improvement in oxidation resistance. Cr-bearing cast irons are resistant to chloride environments and solutions containing strongly oxidizing constituents. Weathering steels, including high content and at least 0.04% Cu, appear to provide adequate resistance to oxidation under temperate conditions. However, data from long-term, high-temperature oxidation studies on weathering steels were not available. From the literature, it appears that the low alloy steels, plain carbon steels, cast steels, and cast irons con-ode at similar rates in an aqueous environment. Alloys containing more than 12% Cr or 36% Ni corrode at a lower rate than plain carbon steels, but pitting may be worse. Short term tests indicate that an alloy of 9Cr-1Mo may result in increased corrosion resistance, however long term data are not available. Austenitic cast irons show the best corrosion resistance. A ranking of total corrosion performance of the materials from most corrosion resistant to least corrosion resistant is: Austenitic Cast Iron; 12% Cr = 36% Ni = 9Cr-1Mo; Carbon Steel = Low Alloy Steels; and Cast Iron. Since the materials to be employed in the Advanced Conceptual Design (ACD) waste package are considered to be corrosion allowance materials, the austenitic cast irons, high Cr steels, high Ni steels and the high Cr-Mo steels should not be considered as candidates for the outer containment barrier. Based upon the oxidation and corrosion data available for carbon steels, low alloy steels, and cast irons, a suitable list of candidate materials for a corrosion allowance outer barrier for an ACD waste package could include, A516, 2.25%Cr -- 1%Mo Steel, and A27.

  3. An Approach to Maximize Weld Penetration During TIG Welding of P91 Steel Plates by Utilizing Image Processing and Taguchi Orthogonal Array

    NASA Astrophysics Data System (ADS)

    Singh, Akhilesh Kumar; Debnath, Tapas; Dey, Vidyut; Rai, Ram Naresh

    2016-06-01

    P-91 is modified 9Cr-1Mo steel. Fabricated structures and components of P-91 has a lot of application in power and chemical industry owing to its excellent properties like high temperature stress corrosion resistance, less susceptibility to thermal fatigue at high operating temperatures. The weld quality and surface finish of fabricated structure of P91 is very good when welded by Tungsten Inert Gas welding (TIG). However, the process has its limitation regarding weld penetration. The success of a welding process lies in fabricating with such a combination of parameters that gives maximum weld penetration and minimum weld width. To carry out an investigation on the effect of the autogenous TIG welding parameters on weld penetration and weld width, bead-on-plate welds were carried on P91 plates of thickness 6 mm in accordance to a Taguchi L9 design. Welding current, welding speed and gas flow rate were the three control variables in the investigation. After autogenous (TIG) welding, the dimension of the weld width, weld penetration and weld area were successfully measured by an image analysis technique developed for the study. The maximum error for the measured dimensions of the weld width, penetration and area with the developed image analysis technique was only 2 % compared to the measurements of Leica-Q-Win-V3 software installed in optical microscope. The measurements with the developed software, unlike the measurements under a microscope, required least human intervention. An Analysis of Variance (ANOVA) confirms the significance of the selected parameters. Thereafter, Taguchi's method was successfully used to trade-off between maximum penetration and minimum weld width while keeping the weld area at a minimum.

  4. High Temperature Irradiation Effects in Selected Generation IV Structural Alloys

    SciTech Connect

    Nanstad, Randy K; McClintock, David A; Hoelzer, David T; Tan, Lizhen; Allen, Todd R.

    2009-01-01

    In the Generation IV Materials Program cross-cutting task, irradiation and testing were carried out to address the issue of high temperature irradiation effects with selected current and potential candidate metallic alloys. The materials tested were (1) a high-nickel iron-base alloy (Alloy 800H); (2) a nickel-base alloy (Alloy 617); (3) two advanced nano-structured ferritic alloys (designated 14YWT and 14WT); and (4) a commercial ferritic-martensitic steel (annealed 9Cr-1MoV). Small tensile specimens were irradiated in rabbit capsules in the High-Flux Isotope Reactor at temperatures from about 550 to 700 C and to irradiation doses in the range 1.2 to 1.6 dpa. The Alloy 800H and Alloy 617 exhibited significant hardening after irradiation at 580 C; some hardening occurred at 660 C as well, but the 800H showed extremely low tensile elongations when tested at 700 C. Notably, the grain boundary engineered 800H exhibited even greater hardening at 580 C and retained a high amount of ductility. Irradiation effects on the two nano-structured ferritic alloys and the annealed 9Cr-1MoV were relatively slight at this low dose.

  5. Creep Deformation, Rupture Analysis, Heat Treatment and Residual Stress Measurement of Monolithic and Welded Grade 91 Steel for Power Plant Components

    NASA Astrophysics Data System (ADS)

    Shrestha, Triratna

    Modified 9Cr-1 Mo (Grade 91) steel is currently considered as a candidate material for reactor pressure vessels (RPVs) and reactor internals for the Very High Temperature Reactor (VHTR), and in fossil-fuel fired power plants at higher temperatures and stresses. The tensile creep behavior of Grade 91 steel was studied in the temperature range of 600°C to 750°C and stresses between 35 MPa and 350 MPa. Heat treatment of Grade 91 steel was studied by normalizing and tempering the steel at various temperatures and times. Moreover, Thermo-Ca1c(TM) calculation was used to predict the precipitate stability and their evolution, and construct carbon isopleths of Grade 91 steel. Residual stress distribution across gas tungsten arc welds (GTAW) in Grade 91 steel was measured by the time-of-flight neutron diffraction using the Spectrometer for Materials Research at Temperature and Stress (SMARTS) diffractometer at Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, NM, USA. Analysis of creep results yielded stress exponents of ˜9-11 in the higher stress regime and ˜1 in the lower stress regime. The creep behavior of Grade 91 steel was described by the modified Bird-Mukherjee-Dorn relation. The rate-controlling creep deformation mechanism in the high stress regime was identified as the edge dislocation climb with a stress exponent of n = 5. On the other hand, the deformation mechanism in the Newtonian viscous creep regime (n = 1) was identified as the Nabarro-Herring creep. Creep rupture data were analyzed in terms of Monkman-Grant relation and Larson-Miller parameter. Creep damage tolerance factor and stress exponent were used to identify the cause of creep damage. The fracture surface morphology of the ruptured specimens was studied by scanning electron microscopy to elucidate the failure mechanisms. Fracture mechanism map for Grade 91 steel was developed based on the available material parameters and experimental observations. The microstructural

  6. Investigation of a Novel NDE Method for Monitoring Thermomechanical Damage and Microstructure Evolution in Ferritic-Martensitic Steels for Generation IV Nuclear Energy Systems

    SciTech Connect

    Nagy, Peter

    2013-09-30

    The main goal of the proposed project is the development of validated nondestructive evaluation (NDE) techniques for in situ monitoring of ferritic-martensitic steels like Grade 91 9Cr-1Mo, which are candidate materials for Generation IV nuclear energy structural components operating at temperatures up to ~650{degree}C and for steam-generator tubing for sodium-cooled fast reactors. Full assessment of thermomechanical damage requires a clear separation between thermally activated microstructural evolution and creep damage caused by simultaneous mechanical stress. Creep damage can be classified as "negligible" creep without significant plastic strain and "ordinary" creep of the primary, secondary, and tertiary kind that is accompanied by significant plastic deformation and/or cavity nucleation and growth. Under negligible creep conditions of interest in this project, minimal or no plastic strain occurs, and the accumulation of creep damage does not significantly reduce the fatigue life of a structural component so that low-temperature design rules, such as the ASME Section III, Subsection NB, can be applied with confidence. The proposed research project will utilize a multifaceted approach in which the feasibility of electrical conductivity and thermo-electric monitoring methods is researched and coupled with detailed post-thermal/creep exposure characterization of microstructural changes and damage processes using state-of-the-art electron microscopy techniques, with the aim of establishing the most effective nondestructive materials evaluation technique for particular degradation modes in high-temperature alloys that are candidates for use in the Next Generation Nuclear Plant (NGNP) as well as providing the necessary mechanism-based underpinnings for relating the two. Only techniques suitable for practical application in situ will be considered. As the project evolves and results accumulate, we will also study the use of this technique for monitoring other GEN IV

  7. 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.

  8. The steel scrap age.

    PubMed

    Pauliuk, Stefan; Milford, Rachel L; Müller, Daniel B; Allwood, Julian M

    2013-04-01

    Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age.

  9. The steel scrap age.

    PubMed

    Pauliuk, Stefan; Milford, Rachel L; Müller, Daniel B; Allwood, Julian M

    2013-04-01

    Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age. PMID:23442209

  10. "The Show"

    ERIC Educational Resources Information Center

    Gehring, John

    2004-01-01

    For the past 16 years, the blue-collar city of Huntington, West Virginia, has rolled out the red carpet to welcome young wrestlers and their families as old friends. They have come to town chasing the same dream for a spot in what many of them call "The Show". For three days, under the lights of an arena packed with 5,000 fans, the state's best…

  11. Fireside corrosion of superheater materials in chlorine containing flue gas

    NASA Astrophysics Data System (ADS)

    Valente, T.

    2001-10-01

    Corrosion resistance of three types of candidate materials for superheater sections under simulated waste incineration conditions was evaluated. A 9Cr1Mo steel, an AISI 310SS, and the Ni-based alloy Sanicro 28 were tested on a laboratory and on a pilot scale with different flue gas compositions (up to 2500 mg/Nm3 of HCl and 1500 mg/Nm3 of fly ash). Laboratory tests were carried out in a furnace up to 200 h. Metal and gas temperature were kept constant at 500 °C. Pilot scale tests were carried out by using a 0.3 × 0.3 m cross-sectional combustor, with flue gas velocity of 5 m/s. Air-cooled probes, designed to operate at a metal temperature of 500 °C and facing gas temperatures as high as 600 °C, were used for 200 h as maximum test time. Qualitative correspondence was found between results obtained by the two sets of experimental tests, but quantitative values were not comparable. Metallographic evaluations, metal loss measurements, and weight loss analysis evidenced as the most suitable alloy Sanicro28. Maximum metal loss observed was 240, 182, and 107 µm, respectively, for 9Cr1Mo, AISI310SS, and Sanicro 28 under the most aggressive conditions. Intergranular corrosion attack was evidenced for AISI310SS, limiting the choice of materials to 9Cr1Mo and Sanicro 28, depending upon the lifetime expected at the design stage.

  12. Low-cycle fatigue behavior of HT-9 alloy in a flowing-lithium environment

    SciTech Connect

    Chopra, O.K.; Smith, D.L.

    1983-06-01

    Low-cycle fatigue data have been obtained on normalized/tempered or lithium-preexposed HT-9 alloy at 755 K in flowing lithium of controlled purity. The results show that the fatigue life of this material decreases with an increase in nitrogen content in lithium. A reduction in strain rate also decreases the fatigue life in high-nitrogen lithium. However, in the range from approx. 4 x 10/sup -4/ to 4 x 10/sup -2/ s/sup -1/, the strain rate has no effect on fatigue life in lithium containing <200 wppM nitrogen. The fatigue life of the HT-9 alloy in low-nitrogen lithium is significantly greater than the fatigue life of Fe-9Cr-1Mo steel or Type 403 martensitic steel in air. Furthermore, a 4.0-Ms preexposure to low-nitrogen lithium has no influence on fatigue life. The reduction in fatigue life in high-nitrogen lithium is attributed to internal corrosive attack of the material. The specimens tested in high-nitrogen lithium show internal corrosion along grain and martensitic lathe boundaries and intergranular fracture. This behavior is not observed in specimens tested in low-nitrogen lithium. Results for a constant-load corrosion test in flowing lithium are also presented.

  13. 9. VIEW SHOWING JUNCTION OF CONCRETE EAST APPROACH SPAN WITH ...

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

    9. VIEW SHOWING JUNCTION OF CONCRETE EAST APPROACH SPAN WITH STEEL SPAN, LOOKING NORTH. NOTE ROCKING CAST STEEL SHOE ATTACHED TO PIER TO ALLOW FOR EXPANSION OF STEEL SPAN - Jensen Bridge, Spanning Green River at Town of Jensen, Jensen, Uintah County, UT

  14. Interior of shop, showing the reheat furnaces; the vehicle in ...

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

    Interior of shop, showing the reheat furnaces; the vehicle in the center is a charging machine the operator of which manipulates steel ingots in the furnace, as well as in the adjacent forging hammers - Bethlehem Steel Corporation, South Bethlehem Works, Tool Steel-Electric Furnace Shop, Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

  15. Hydrogen Permeation in Nanostructured Bainitic Steel

    NASA Astrophysics Data System (ADS)

    Kazum, Oluwole; Beladi, Hossein; Timokhina, Ilana B.; He, Yinghe; Bobby Kannan, M.

    2016-07-01

    Hydrogen permeation of nanostructured bainitic steel, produced at two different transformation temperatures, i.e., 473.15 K (200 °C) BS-200 and 623.15 K (350 °C) BS-350, was determined using Devanathan-Stachurski hydrogen permeation cell and compared with that of mild steel. Nanostructured bainitic steel showed lower effective diffusivity of hydrogen as compared to the mild steel. The BS-200 steel, which exhibited higher volume fraction of bainitic ferrite phase, showed lower effective diffusivity than BS-350 steel. The finer microstructural constituents (bainitic ferrite laths and retained austenite films) and higher dislocation density in the bainitic ferrite phase of BS-200 steel can be attributed to its lower effective diffusivity as compared to BS-350 steel and mild steel.

  16. Hydrogen Permeation in Nanostructured Bainitic Steel

    NASA Astrophysics Data System (ADS)

    Kazum, Oluwole; Beladi, Hossein; Timokhina, Ilana B.; He, Yinghe; Bobby Kannan, M.

    2016-10-01

    Hydrogen permeation of nanostructured bainitic steel, produced at two different transformation temperatures, i.e., 473.15 K (200 °C) BS-200 and 623.15 K (350 °C) BS-350, was determined using Devanathan-Stachurski hydrogen permeation cell and compared with that of mild steel. Nanostructured bainitic steel showed lower effective diffusivity of hydrogen as compared to the mild steel. The BS-200 steel, which exhibited higher volume fraction of bainitic ferrite phase, showed lower effective diffusivity than BS-350 steel. The finer microstructural constituents (bainitic ferrite laths and retained austenite films) and higher dislocation density in the bainitic ferrite phase of BS-200 steel can be attributed to its lower effective diffusivity as compared to BS-350 steel and mild steel.

  17. Protective coatings for alloys in contact with molten drawsalt (NaNO/sub 3/-KNO/sub 3/)

    SciTech Connect

    Carling, R.W.; Bradshaw, R.W.; Mar, R.W.

    1982-09-01

    Molten drawsalt (NaNO/sub 3/-KNO/sub 3/) is being considered as the energy transfer and storage medium for many solar central receiver applications. In an effort to reduce the cost of the containment material while maintaining corrosion resistance, alloys with aluminide coatings have been examined while in contact with molten drawsalt for more than 6000 hours at 600/sup 0/C. The alloys examined were 2-1/4 Cr-1 Mo, 5 Cr-1/2 Mo, and 9 Cr-1 Mo low-alloy steels, and 316 stainless steel. The results show a steady, albeit slow, net weight loss over the course of the experiment. The weight loss has been attributed to spalling of Al/sub 2/O/sub 3/ from the surface (the occurrence of Al/sub 2/O/sub 3/ is a result of the aluminizing process) and dissolution of corrosion products NaAlO/sub 2/ and/or NaFeO/sub 2/ during post-immersion handling. Scanning electron micrographs of exposed surfaces revealed little or no corrosion of the base metal. It has been concluded that aluminide coated alloys could provide significant cost savings (approx. 50%) relative to Incoloy 800, and provide at least equivalent corrosion resistance.

  18. Structural Amorphous Steels

    NASA Astrophysics Data System (ADS)

    Lu, Z. P.; Liu, C. T.; Thompson, J. R.; Porter, W. D.

    2004-06-01

    Recent advancement in bulk metallic glasses, whose properties are usually superior to their crystalline counterparts, has stimulated great interest in fabricating bulk amorphous steels. While a great deal of effort has been devoted to this field, the fabrication of structural amorphous steels with large cross sections has remained an alchemist’s dream because of the limited glass-forming ability (GFA) of these materials. Here we report the discovery of structural amorphous steels that can be cast into glasses with large cross-section sizes using conventional drop-casting methods. These new steels showed interesting physical, magnetic, and mechanical properties, along with high thermal stability. The underlying mechanisms for the superior GFA of these materials are discussed.

  19. Improvement of ASME NH for Grade 91

    SciTech Connect

    Bernard Riou

    2007-10-09

    This report has been prepared in the context of Task 3 of the ASME/DOE Gen IV material project. It has been identified that creep-fatigue evaluation procedures presently available in ASME (1) and RCC-MR (2) have been mainly developed for austenitic stainless steels and may not be suitable for cyclic softening materials such as mod 9 Cr 1 Mo steel (grade 91). The aim of this document is, starting from experimental test results, to perform a review of the procedures and, if necessary, provide recommendations for their improvements.

  20. Atmosphere

    NASA Astrophysics Data System (ADS)

    Ghosh, D.; Mitra, S. K.

    2014-05-01

    This paper investigates the high-temperature corrosion behavior of microstructurally different regions of the weldment of 9 Cr-1 Mo steel used in thermal power plant boiler in SO2 + O2 environment. The weldment is produced by tungsten inert gas welding method, and the different regions of the weldment (weld metal, heat-affected zone, and base metal) are exposed in SO2 + O2 (ratio 2:1) environment at 973 K for 120 h. The reaction kinetics and corrosion growth rate of different regions of weldment in isothermal condition are evaluated. The post corroded scales of the different specimens are studied in SEM, EDS, and XRD. The results indicate that the weld metal shows higher corrosion rate followed by HAZ and base metal. The higher rate of corrosion of weldmetal is mainly attributed to the least protective inner scale of Cr2O3 with minimum Cr Content. This is due to the formation of delta ferrite, which leads to the precipitation of the Cr-based secondary phases and depletes the free Cr from the matrix. The thermal cycles during welding at high temperature are favorable for the formation of delta ferrite. On the other hand, in absence of delta ferrite, the base metal and HAZ regions of the weldment show lower corrosion rate than weld metal. The difference in corrosion rate in the three regions of the weldment is supplemented by post-corroded scale characterizations.

  1. Comparative Structural Strength Research of Hardened Carbon Steel and Hot-Rolled Alloy Steel

    NASA Astrophysics Data System (ADS)

    Bogomolov, A. V.; Zhakupov, A. N.; Kanayev, A. T.; Sikach, I. A.; Tugumov, K. K.

    2016-08-01

    Experiments on quantitative evaluation of fatigue strength showed that St5ps and St5sp carbon steels with A400 strength class can be fully applied for erection of constructions and buildings having cyclical loads during operation. Study of corrosion resistance of hardened carbon steel in comparison with hot-rolled alloy steel consists in difference in structures and hence, difference in intensity of electric and chemical processes featuring presence of steel in concrete. Structure of St5sp steel with A400 strength class in surface area has significantly less corrosion rate than ferritic-perlitic structure of 35GS steel with A400 strength class.

  2. 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.

  3. Monitoring of weathering steel structures. The induction ultrasonic thickness testers

    NASA Astrophysics Data System (ADS)

    McKenzie, M.

    Long term corrosion tests carried out in the UK show that weathering steels continue to corrode at a finite rate. It is therefore necessary to use thicker steel and to monitor the corrosion. An ultrasonic instrument to measure residual steel thickness was assessed. This measures steel thickness through a rust layer, requires no couplant to transmit the ultrasound into the steel and gives only the steel thickness not the thickness of the steel plus a layer of rust. This instrument provides a suitable method of measuring the residual steel thickness on weathering steel structures where corrosion has been generally uniform. However, the instrument can give no information on localized roughness or pitting of the underlying steel surface and it would seem worthwhile to include test specimens in any monitoring scheme so that the surface condition of the steel can be assessed.

  4. 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

  5. 42. CAPE COD AIR STATION PAVE PAWS FACILITY SHOWING ...

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

    42. CAPE COD AIR STATION PAVE PAWS FACILITY - SHOWING BUILDING "RED IRON" STEEL STRUCTURE AT 46T DAY OF STEEL CONSTRUCTION. "BUILDING TOPPED OFF, 7 JULY, 1974. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

  6. 8. COPY OF PHOTOGRAPH TAKEN APRIL 6, 1914, SHOWING OPEN ...

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

    8. COPY OF PHOTOGRAPH TAKEN APRIL 6, 1914, SHOWING OPEN HEARTH BUILDING UNDER CONSTRUCTION. THE FOUNDATION FOR THE MIXER BUILDING CAN BE SEEN IN LEFT FOREGROUND, VIEW LOOKING NORTH PHOTO COURTESY REPUBLIC STEEL CORPORATION. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  7. Ways of improvement for the materials of sodium cooled fast reactors

    SciTech Connect

    Horowitz, E.

    2012-07-01

    The French sodium cooled prototype reactor ASTRID will take into account 'Generation IV' requirements, especially a long operational life-time (60 years) and a high efficiency. The good behavior of austenitic steel AISI316L(N), should be confirmed for a use, in moderately irradiated and unirradiated parts of ASTRID. Parts recovered from dismantled French sodium-cooled reactors will be characterized. Further experiments must be carried out concerning ageing of these components. Other materials will be chosen for fuel wrapping and cladding, in order to reduce creep and swelling under irradiation, (either conventional, or oxide-dispersed strengthened steels (ODSS). Corrosion of ODSS in the presence of sodium needs a serious assessment The lifetime of primary pumps components made of Duplex steels should also be assessed. The disruptions in steam generator tubes should be minimized and controlled; therefore, optimised designs and geometries must be established before defining the corresponding materials. Either Modified 9Cr1Mo or Incoloy 800H, might be candidates;it will be necessary to check whether austenitic steels are compatible with Modified 9Cr1Mo or Incoloy 800H in the same circuit. For all materials, the best manufacturing processes must be combined with thermal, mechanical treatments; calculations of phase diagrams (CALPHAD) might be used to optimise both treatments and chemical compositions. (authors)

  8. Corrosion behaviour of galvanized steel and electroplating steel in aqueous solution: AC impedance study and XPS

    NASA Astrophysics Data System (ADS)

    Lebrini, M.; Fontaine, G.; Gengembre, L.; Traisnel, M.; Lerasle, O.; Genet, N.

    2008-08-01

    The efficiency of a new triazole derivative, namely, 2-{(2-hydroxyethyl)[(4-methyl-1 H-1,2,3-benzotriazol-1-yl)methyl]amino}ethanol (TTA) has been studied for corrosion inhibition of galvanized steel and electroplating steel in aqueous solution. Corrosion inhibition was studied using electrochemical impedance spectroscopy (EIS). These studies have shown that TTA was a very good inhibitor. Data obtained from EIS show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. The corrosion behaviour of galvanized steel and electroplating steel in aqueous solution was also investigated in the presence of 4-methyl-1 H-benzotriazole (TTA unsubstituted) by EIS. These studies have shown that the ability of the molecule to adsorb on the steel surface was dependent on the group in triazole ring substituent. X-ray photoelectron spectroscopy surface analysis with TTA shows that it chemisorbed on surface of galvanized steel and electroplating steel.

  9. Investigation of austenitic alloys for advanced heat recovery and hot-gas cleanup systems

    SciTech Connect

    Swindeman, R.W.

    1997-12-01

    Materials properties were collected for the design and construction of structural components for use in advanced heat recovery and hot gas cleanup systems. Alloys systems included 9Cr-1Mo-V steel, modified 316 stainless steel, modified type 310 stainless steel, modified 20Cr-25Ni-Nb stainless steel, and modified alloy 800. Experimental work was undertaken to expand the databases for potentially useful alloys. Types of testing included creep, stress-rupture, creep-crack growth, fatigue, and post-exposure short-time tensile tests. Because of the interest in relatively inexpensive alloys for service at 700 C and higher, research emphasis was placed on a modified type 310 stainless steel and a modified 20Cr-25Ni-Nb stainless steel. Both steels were found to have useful strength to 925 C with good weldability and ductility.

  10. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    SciTech Connect

    Swindeman, R.W.; Ren, W.

    1996-08-01

    Materials properties were collected for the design and construction of structural components for use in advanced heat recovery and hot gas cleanup systems. Alloys systems included 9Cr-1Mo-V steel, modified 316 stainless steel, modified type 310 stainless steel, modified 20Cr-25Ni-Nb stainless steel, modified alloy 800, and two sulfidation resistant alloys: HR160 and HR120. Experimental work was undertaken to expand the databases for potentially useful alloys. Types of testing included creep, stress-rupture, creep-crack growth, fatigue, and post-exposure short-time tensile tests. Because of the interest in relatively inexpensive alloys for service at 700{degrees}C and higher, research emphasis was placed on a modified type 310 stainless steel and a modified 20Cr-25Ni-Nb stainless steel. Both steels were found to have useful strength to 925{degrees}C with good weldability and ductility.

  11. Intelligent Modeling Combining Adaptive Neuro Fuzzy Inference System and Genetic Algorithm for Optimizing Welding Process Parameters

    NASA Astrophysics Data System (ADS)

    Gowtham, K. N.; Vasudevan, M.; Maduraimuthu, V.; Jayakumar, T.

    2011-04-01

    Modified 9Cr-1Mo ferritic steel is used as a structural material for steam generator components of power plants. Generally, tungsten inert gas (TIG) welding is preferred for welding of these steels in which the depth of penetration achievable during autogenous welding is limited. Therefore, activated flux TIG (A-TIG) welding, a novel welding technique, has been developed in-house to increase the depth of penetration. In modified 9Cr-1Mo steel joints produced by the A-TIG welding process, weld bead width, depth of penetration, and heat-affected zone (HAZ) width play an important role in determining the mechanical properties as well as the performance of the weld joints during service. To obtain the desired weld bead geometry and HAZ width, it becomes important to set the welding process parameters. In this work, adaptative neuro fuzzy inference system is used to develop independent models correlating the welding process parameters like current, voltage, and torch speed with weld bead shape parameters like depth of penetration, bead width, and HAZ width. Then a genetic algorithm is employed to determine the optimum A-TIG welding process parameters to obtain the desired weld bead shape parameters and HAZ width.

  12. Utilization of structural steel in buildings.

    PubMed

    Moynihan, Muiris C; Allwood, Julian M

    2014-08-01

    Over one-quarter of steel produced annually is used in the construction of buildings. Making this steel causes carbon dioxide emissions, which climate change experts recommend be reduced by half in the next 37 years. One option to achieve this is to design and build more efficiently, still delivering the same service from buildings but using less steel to do so. To estimate how much steel could be saved from this option, 23 steel-framed building designs are studied, sourced from leading UK engineering firms. The utilization of each beam is found and buildings are analysed to find patterns. The results for over 10 000 beams show that average utilization is below 50% of their capacity. The primary reason for this low value is 'rationalization'-providing extra material to reduce labour costs. By designing for minimum material rather than minimum cost, steel use in buildings could be drastically reduced, leading to an equivalent reduction in 'embodied' carbon emissions.

  13. Corrosion of alloy steels in oil field fluids

    SciTech Connect

    Martin, R.L.

    1987-01-01

    Laboratory and field tests have been conducted on two low alloy and two higher alloy steels at a range of brine salinities and sulfide contents typical of oil well production fluids. AISI types 4130 and 4340 show the same behavior in these fluids as mild steel. AISI type 410 stainless steel and 9% chromium - 1% molybdenum steel corrode at rates as great as that of mild steel at higher chloride or sulfide concentrations. Special corrosion inhibitors are required for higher alloy steels when they are exposed to these conditions.

  14. View southwest, wharf A and timber breakwater, showing sawn off ...

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

    View southwest, wharf A and timber breakwater, showing sawn off section and steel lift tower - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  15. 6. Detail of interior bin wall section, during demolition. Shows ...

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

    6. Detail of interior bin wall section, during demolition. Shows alternating courses of channel tile with steel bands and largers hollow tile. - Saint Anthony Elevator No. 3, 620 Malcom Avenue, Southeast, Minneapolis, Hennepin County, MN

  16. 45. SOUTHERN INTERIOR VIEW OF MOULD CONDITIONING BUILDING SHOWING FINK ...

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

    45. SOUTHERN INTERIOR VIEW OF MOULD CONDITIONING BUILDING SHOWING FINK TRUSSES AND CORRUGATED METAL SHEETING. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  17. 64. General view looking northwest showing Rust Co. boiler stacks ...

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

    64. General view looking northwest showing Rust Co. boiler stacks with stock bin trestle in foreground and regenerative stoves in background. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  18. 6. DETAIL OF UNITEDTOD TWINTANDEM STEAM ENGINE, SHOWING CRANK END ...

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

    6. DETAIL OF UNITED-TOD TWIN-TANDEM STEAM ENGINE, SHOWING CRANK END OF LOW PRESSURE SIDE OF ENGINE. - Republic Iron & Steel Company, Youngstown Works, Blooming Mill & Blooming Mill Engines, North of Poland Avenue, Youngstown, Mahoning County, OH

  19. 26. INTERIOR VIEW SHOWING ROW OF TIMBER SUPPORT TOWERS BUILT ...

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

    26. INTERIOR VIEW SHOWING ROW OF TIMBER SUPPORT TOWERS BUILT AS TEMPORARY TRUSS REINFORCEMENT (NOTE STEEL STRUCTURES ATOP TIMBER BRACING) - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  20. 17. ENGINE SIDE OF 48' MILL STAND SHOWING POWER CONNECTIONS ...

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

    17. ENGINE SIDE OF 48' MILL STAND SHOWING POWER CONNECTIONS TO PINION STAND AND VERTICAL ROLL SCREWDOWN MECHANISM. Martin Stupich, Photographer, 1989. - U.S. Steel Homestead Works, 48" Plate Mill, Along Monongahela River, Homestead, Allegheny County, PA

  1. 18. OPERATOR'S SIDE OF 48' MILL STAND SHOWING DIALS, VERTICAL ...

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

    18. OPERATOR'S SIDE OF 48' MILL STAND SHOWING DIALS, VERTICAL ROLL SCREWDOWN, AND VIEW THROUGH HOUSING TO PINION STAND. Martin Stupich, Photographer, 1989. - U.S. Steel Homestead Works, 48" Plate Mill, Along Monongahela River, Homestead, Allegheny County, PA

  2. 9. VIEW OF SOUTH SIDE OF BRIDGE RETAINING WALL, SHOWING ...

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

    9. VIEW OF SOUTH SIDE OF BRIDGE RETAINING WALL, SHOWING SMOOTH STEEL REBAR SET IN CONCRETE, LOOKING SOUTH - Box Elder Creek Arch Bridge, Spanning former channel of South fork of Box Elder Creek, Mantua, Box Elder County, UT

  3. 22. General view from the southwest showing No. 1 Furnace ...

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

    22. General view from the southwest showing No. 1 Furnace at left and hot blast stoves in center. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  4. Interior general view of stair well at southwest corner showing ...

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

    Interior general view of stair well at southwest corner showing stair enclosure and typical steel fire door; view to southwest. - Lawrence Machine Shop, Building No. 4, 70 General Street, Lawrence, Essex County, MA

  5. 3. Perspective view of north end of Bunker 103 showing ...

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

    3. Perspective view of north end of Bunker 103 showing north set of steel doors. Camera pointed NW. - Puget Sound Naval Shipyard, Munitions Storage Bunker, Naval Ammunitions Depot, North of Campbell Trail, Bremerton, Kitsap County, WA

  6. 38. Base of No. 2 Furnace showing iron runner to ...

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

    38. Base of No. 2 Furnace showing iron runner to ladle car on floor of casting shed. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  7. 19. DETAILED OBLIQUE VIEW SOUTHSOUTHEAST OF FURNACE 2, SHOWING PLATFORM ...

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

    19. DETAILED OBLIQUE VIEW SOUTH-SOUTHEAST OF FURNACE 2, SHOWING PLATFORM AT UPPER LEFT HOLDING PULLEY SYSTEM AND ELECTRIC MOTOR TO ACTIVATE DOORS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  8. 15. DETAILED OBLIQUE VIEW SOUTHWEST OF FURNACE 1, SHOWING COUNTERWEIGHTED ...

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

    15. DETAILED OBLIQUE VIEW SOUTHWEST OF FURNACE 1, SHOWING COUNTER-WEIGHTED PIVOT ARMS TO RAISE AND LOWER DOORS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  9. 21. DETAILED FRONTAL VIEW WEST OF FURNACE 2, SHOWING MOUTHS ...

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

    21. DETAILED FRONTAL VIEW WEST OF FURNACE 2, SHOWING MOUTHS WITH ROLLERS FOR MOVING TRAYS IN AND OUT OF THE OVENS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  10. 6. OVERALL OBLIQUE VIEW SOUTHSOUTHWEST, SHOWING NORTH & WEST FACADES ...

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

    6. OVERALL OBLIQUE VIEW SOUTH-SOUTHWEST, SHOWING NORTH & WEST FACADES WITH SHED ROOF BUILDING 8 JUTTING FROM NORTH FACADE OF WEST BAY. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  11. 6. DETAIL VIEW AT ROAD LEVEL, SHOWING STEELDECK GRATING AND ...

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

    6. DETAIL VIEW AT ROAD LEVEL, SHOWING STEEL-DECK GRATING AND JUNCTURE OF ARCH AND PAVEMENT - Benson Street Concrete Bowstring Bridge, Spanning Mill Creek at Benson Street, Lockland, Hamilton County, OH

  12. Interior view at top of parachute drying tower showing original ...

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

    Interior view at top of parachute drying tower showing original steel wall-mounted ladder, facing southwest. - Albrook Air Force Station, Parachute & Armament Building, 200 feet north of Andrews Boulevard, Balboa, Former Panama Canal Zone, CZ

  13. 8. EAST PORTAL AND DECK VIEW, FROM EAST, SHOWING PORTAL ...

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

    8. EAST PORTAL AND DECK VIEW, FROM EAST, SHOWING PORTAL CONFIGURATION AND LATERAL BRACING, STEEL MESH FLOOR, METAL RAILINGS, AND PORTION OF EAST APPROACH - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  14. 7. WEST PORTAL AND DECK VIEW, FROM WEST, SHOWING PORTAL ...

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

    7. WEST PORTAL AND DECK VIEW, FROM WEST, SHOWING PORTAL CONFIGURATION AND LATERAL BRACING, STEEL MESH FLOOR, AND METAL RAILINGS - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  15. 15. DETAIL, UNDERSIDE OF DECK, FROM BELOW AND WEST, SHOWING ...

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

    15. DETAIL, UNDERSIDE OF DECK, FROM BELOW AND WEST, SHOWING STRUCTURAL CONFIGURATION, INCLUDING FLOOR BEAMS, STRINGERS, BRACING, AND STEEL MESH DECK - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  16. 12. DETAIL OF UNDERSIDE OF BRIDGE, SHOWING LOWER CHORDS, FLOOR ...

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

    12. DETAIL OF UNDERSIDE OF BRIDGE, SHOWING LOWER CHORDS, FLOOR BEAMS, STRINGERS AND UNDERSIDE OF STEEL DECKING. VIEW TO WEST. - Whispering Pines Bridge, Spanning East Verde River at Forest Service Control Road, Payson, Gila County, AZ

  17. 22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL ...

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

    22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL CONSTRUCTION. CONCRETE PAD AT LEFT IS SITE OF FORMER FURNACE USED TO HEAT URANIUM BILLETS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  18. INTERIOR VIEW LOOKING NORTH, SHOWING GE CONTROL PANEL, RHEOSTATS AND ...

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

    INTERIOR VIEW LOOKING NORTH, SHOWING GE CONTROL PANEL, RHEOSTATS AND METERS FOR NO. 2 FURNACE. METER TO THE LEFT IS WESTINGHOUSE. - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  19. INTERIOR VIEW LOOKING SOUTHWEST, SHOWING HEROULT NO. 2 FURNACE (ca. ...

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

    INTERIOR VIEW LOOKING SOUTHWEST, SHOWING HEROULT NO. 2 FURNACE (ca. 1920) AND DC MOTORS (which raise and lower the bus bars) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  20. INTERIOR VIEW LOOKING NORTHEAST, SHOWING FURNACE NO. 1 (ca. 1910. ...

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

    INTERIOR VIEW LOOKING NORTHEAST, SHOWING FURNACE NO. 1 (ca. 1910. Nameplate reads: "Heroult Electric Furnace, Capacity 6 tons, Built by American Bridge Company, Pencoyd, PA, No. 33") - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  1. INTERIOR VIEW LOOKING EAST, SHOWING HEROULT NO. 2 FURNACE (ca. ...

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

    INTERIOR VIEW LOOKING EAST, SHOWING HEROULT NO. 2 FURNACE (ca. 1920) AND DETAIL OF CABLES AND BUS BARS (which convey power to electrodes) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  2. INTERIOR VIEW LOOKING SOUTHWEST SHOWING NO. 1 FURNACE. TO RIGHT ...

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

    INTERIOR VIEW LOOKING SOUTHWEST SHOWING NO. 1 FURNACE. TO RIGHT ARE D.C. MOTORS (which raise and lower the bus bars) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  3. Materials technology for coal-conversion processes. Progress report, July-September 1980

    SciTech Connect

    1980-12-01

    Failure analysis of the refractory lining of the Grand Forks Energy Technology Center slagging gasifier revealed that sodium hydroxide had reacted with the refractory, causing a large volume change and consequent spallation. Laboratory studies on pressure coupling of acoustic waveguides to pressure boundaries for long-term erosive wear measurements show that the use of annealed copper foil (0.25-0.76 mm (10-30 mil) thick) with a contact pressure of 50-70 MPa (7-10 ksi) can yield satisfactory coupling in the presence of thermal cycling. High-temperature corrosion studies have been initiated to investigate effects of deposits such as CaO and CaSO/sub 4/ on corrosion rates of Fe-2-1/4Cr-1Mo and Fe-9Cr-1Mo ferritic steels. Erosion studies at room temperature and atmospheric pressure were conducted on 1015 carbon steel, 304 and 310 stainless steel, Incoloy 800, and Stellite 6B. Impact particles were 150-..mu..m Al/sub 2/O/sub 3/ with impact angles of 16-81/sup 0/. Weight-loss measurements are in good agreement with prior work. Materials studies for instrumentation included studies of thermowells at the U-Gas plant run by IGT. Analysis of a product gas line from Bi-Gas indicates that failure was caused by caustic- or oxygen-assisted stress-corrosion cracking. A product gas line expansion joint from U-gas was also examined; at present, chloride-induced pitting seems to have been the cause of this failure, which was initiated at the inner surface.

  4. Anodized Steel Electrodes for Supercapacitors.

    PubMed

    Sagu, Jagdeep S; Wijayantha, K G Upul; Bohm, Mallika; Bohm, Siva; Kumar Rout, Tapan

    2016-03-01

    Steel was anodized in 10 M NaOH to enhance its surface texture and internal surface area for application as an electrode in supercapacitors. A mechanism was proposed for the anodization process. Field-emission gun scanning electron microscopy (FEGSEM) studies of anodized steel revealed that it contains a highly porous sponge like structure ideal for supercapacitor electrodes. X-ray photoelectron spectroscopy (XPS) measurements showed that the surface of the anodized steel was Fe2O3, whereas X-ray diffraction (XRD) measurements indicated that the bulk remained as metallic Fe. The supercapacitor performance of the anodized steel was tested in 1 M NaOH and a capacitance of 18 mF cm(-2) was obtained. Cyclic voltammetry measurements showed that there was a large psueudocapacitive contribution which was due to oxidation of Fe to Fe(OH)2 and then further oxidation to FeOOH, and the respective reduction of these species back to metallic Fe. These redox processes were found to be remarkably reversible as the electrode showed no loss in capacitance after 10000 cycles. The results demonstrate that anodization of steel is a suitable method to produce high-surface-area electrodes for supercapacitors with excellent cycling lifetime. PMID:26891093

  5. Anodized Steel Electrodes for Supercapacitors.

    PubMed

    Sagu, Jagdeep S; Wijayantha, K G Upul; Bohm, Mallika; Bohm, Siva; Kumar Rout, Tapan

    2016-03-01

    Steel was anodized in 10 M NaOH to enhance its surface texture and internal surface area for application as an electrode in supercapacitors. A mechanism was proposed for the anodization process. Field-emission gun scanning electron microscopy (FEGSEM) studies of anodized steel revealed that it contains a highly porous sponge like structure ideal for supercapacitor electrodes. X-ray photoelectron spectroscopy (XPS) measurements showed that the surface of the anodized steel was Fe2O3, whereas X-ray diffraction (XRD) measurements indicated that the bulk remained as metallic Fe. The supercapacitor performance of the anodized steel was tested in 1 M NaOH and a capacitance of 18 mF cm(-2) was obtained. Cyclic voltammetry measurements showed that there was a large psueudocapacitive contribution which was due to oxidation of Fe to Fe(OH)2 and then further oxidation to FeOOH, and the respective reduction of these species back to metallic Fe. These redox processes were found to be remarkably reversible as the electrode showed no loss in capacitance after 10000 cycles. The results demonstrate that anodization of steel is a suitable method to produce high-surface-area electrodes for supercapacitors with excellent cycling lifetime.

  6. Television Quiz Show Simulation

    ERIC Educational Resources Information Center

    Hill, Jonnie Lynn

    2007-01-01

    This article explores the simulation of four television quiz shows for students in China studying English as a foreign language (EFL). It discusses the adaptation and implementation of television quiz shows and how the students reacted to them.

  7. Virtual Steel Connection Sculpture--Student Learning Assessment

    ERIC Educational Resources Information Center

    Chou, Karen C.; Moaveni, Saeed; Drane, Denise

    2016-01-01

    A Virtual Steel Connection Sculpture was developed through a grant from the National Science Foundation. The Virtual Sculpture is an interactive tool that shows students and anyone interested in connections how steel members are connected. This tool is created to complement students' steel design courses. The features of this educational tool,…

  8. Ultrahigh carbon steels, Damascus steels, and superplasticity

    SciTech Connect

    Sherby, O.D.; Wadsworth, J.

    1997-04-01

    The processing properties of ultrahigh carbon steels (UHCSs) have been studied at Stanford University over the past twenty years. These studies have shown that such steels (1 to 2.1% C) can be made superplastic at elevated temperature and can have remarkable mechanical properties at room temperature. It was the investigation of these UHCSs that eventually brought us to study the myths, magic, and metallurgy of ancient Damascus steels, which in fact, were also ultrahigh carbon steels. These steels were made in India as castings, known as wootz, possibly as far back as the time of Alexander the Great. The best swords are believed to have been forged in Persia from Indian wootz. This paper centers on recent work on superplastic UHCSs and on their relation to Damascus steels. 32 refs., 6 figs.

  9. Mechanical properties of irradiated 9Cr-2WVTa steel

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.; Rieth, M.

    1998-09-01

    An Fe-9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa) steel has excellent strength and impact toughness before and after irradiation in the Fast Flux Test Facility and the High Flux Reactor (HFR). The ductile-brittle transition temperature (DBTT) increased only 32 C after 28 dpa at 365 C in FFTF, compared to a shift of {approx}60 C for a 9Cr-2WV steel--the same as the 9Cr-2WVTa steel but without tantalum. This difference occurred despite the two steels having similar tensile but without tantalum. This difference occurred despite the two steels having similar tensile properties before and after irradiation. The 9Cr-2WVTa steel has a smaller prior-austenite grain size, but otherwise microstructures are similar before irradiation and show similar changes during irradiation. The irradiation behavior of the 9Cr-2WVTa steel differs from the 9Cr-2WV steel and other similar steels in two ways: (1) the shift in DBTT of the 9Cr-2WVTa steel irradiated in FFTF does not saturate with fluence by {approx}28 dpa, whereas for the 9Cr-2WV steel and most similar steels, saturation occurs at <10 dpa, and (2) the shift in DBTT for 9Cr-2WVTa steel irradiated in FFTF and HFR increased with irradiation temperature, whereas it decreased for the 9Cr-2WV steel, as it does for most similar steels. The improved properties of the 9Cr-2WVTa steel and the differences with other steels were attributed to tantalum in solution.

  10. VIEW SHOWING THE ENTRY THROUGH THE RETAINING WALL (FOREGROUND) TO ...

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

    VIEW SHOWING THE ENTRY THROUGH THE RETAINING WALL (FOREGROUND) TO THE CONCRETE SLAB. NOTE THE 1¾" MOUNTING BOLTS FOR THE STEEL PLATE BASE OF THE 5" GUN, SET IN THE GUN BLOCK. STEEL REINFORCING RODS PROTRUDING FROM THE BROKEN TOPS OF THE RETAINING WALLS ARE ALSO VISIBLE. VIEW FACING EAST - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, South Gun Emplacement, Ford Island, Pearl City, Honolulu County, HI

  11. A Holographic Road Show.

    ERIC Educational Resources Information Center

    Kirkpatrick, Larry D.; Rugheimer, Mac

    1979-01-01

    Describes the viewing sessions and the holograms of a holographic road show. The traveling exhibits, believed to stimulate interest in physics, include a wide variety of holograms and demonstrate several physical principles. (GA)

  12. Steel Creek wildlife: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1987

    SciTech Connect

    Giffin, M.A.; Patterson, K.K.

    1988-03-01

    Reptile and amphibian populations in Steel Creek below L-Lake were assessed in monthly or quarterly sampling programs. Thirty-eight species of reptiles or amphibians were collected during 1987 in the Steel Creek corridor below the L-Lake impoundment, and in the delta and channel. Juvenile turtles and alligators, and larval amphibians were observed or collected during the study, indicating continued reproduction in Steel Creek. The reptile and amphibian populations in Steel Creek show no indication of any effect due to the impoundment of the lake or the operation of L-Reactor. Waterfowl and associated birds in Steel Creek below L-Lake were observed, in conjunction with other sampling programs, during winter--spring and fall--winter migrations. Nine species of waterfowl and five species of associated birds were observed in 1987 in the Steel Creek corridor below the L-Lake impoundment and in the delta and channel.

  13. Comminuting irradiated ferritic steel

    DOEpatents

    Bauer, Roger E.; Straalsund, Jerry L.; Chin, Bryan A.

    1985-01-01

    Disclosed is a method of comminuting irradiated ferritic steel by placing the steel in a solution of a compound selected from the group consisting of sulfamic acid, bisulfate, and mixtures thereof. The ferritic steel is used as cladding on nuclear fuel rods or other irradiated components.

  14. The Ozone Show.

    ERIC Educational Resources Information Center

    Mathieu, Aaron

    2000-01-01

    Uses a talk show activity for a final assessment tool for students to debate about the ozone hole. Students are assessed on five areas: (1) cooperative learning; (2) the written component; (3) content; (4) self-evaluation; and (5) peer evaluation. (SAH)

  15. Show What You Know

    ERIC Educational Resources Information Center

    Eccleston, Jeff

    2007-01-01

    Big things come in small packages. This saying came to the mind of the author after he created a simple math review activity for his fourth grade students. Though simple, it has proven to be extremely advantageous in reinforcing math concepts. He uses this activity, which he calls "Show What You Know," often. This activity provides the perfect…

  16. Showing What They Know

    ERIC Educational Resources Information Center

    Cech, Scott J.

    2008-01-01

    Having students show their skills in three dimensions, known as performance-based assessment, dates back at least to Socrates. Individual schools such as Barrington High School--located just outside of Providence--have been requiring students to actively demonstrate their knowledge for years. The Rhode Island's high school graduating class became…

  17. Stage a Water Show

    ERIC Educational Resources Information Center

    Frasier, Debra

    2008-01-01

    In the author's book titled "The Incredible Water Show," the characters from "Miss Alaineus: A Vocabulary Disaster" used an ocean of information to stage an inventive performance about the water cycle. In this article, the author relates how she turned the story into hands-on science teaching for real-life fifth-grade students. The author also…

  18. What Do Maps Show?

    ERIC Educational Resources Information Center

    Geological Survey (Dept. of Interior), Reston, VA.

    This curriculum packet, appropriate for grades 4-8, features a teaching poster which shows different types of maps (different views of Salt Lake City, Utah), as well as three reproducible maps and reproducible activity sheets which complement the maps. The poster provides teacher background, including step-by-step lesson plans for four geography…

  19. Obesity in show cats.

    PubMed

    Corbee, R J

    2014-12-01

    Obesity is an important disease with a high prevalence in cats. Because obesity is related to several other diseases, it is important to identify the population at risk. Several risk factors for obesity have been described in the literature. A higher incidence of obesity in certain cat breeds has been suggested. The aim of this study was to determine whether obesity occurs more often in certain breeds. The second aim was to relate the increased prevalence of obesity in certain breeds to the official standards of that breed. To this end, 268 cats of 22 different breeds investigated by determining their body condition score (BCS) on a nine-point scale by inspection and palpation, at two different cat shows. Overall, 45.5% of the show cats had a BCS > 5, and 4.5% of the show cats had a BCS > 7. There were significant differences between breeds, which could be related to the breed standards. Most overweight and obese cats were in the neutered group. It warrants firm discussions with breeders and cat show judges to come to different interpretations of the standards in order to prevent overweight conditions in certain breeds from being the standard of beauty. Neutering predisposes for obesity and requires early nutritional intervention to prevent obese conditions. PMID:24612018

  20. Show Me the Way

    ERIC Educational Resources Information Center

    Dicks, Matthew J.

    2005-01-01

    Because today's students have grown up steeped in video games and the Internet, most of them expect feedback, and usually gratification, very soon after they expend effort on a task. Teachers can get quick feedback to students by showing them videotapes of their learning performances. The author, a 3rd grade teacher describes how the seemingly…

  1. The Art Show

    ERIC Educational Resources Information Center

    Scolarici, Alicia

    2004-01-01

    This article describes what once was thought to be impossible--a formal art show extravaganza at an elementary school with 1,000 students, a Department of Defense Dependent School (DODDS) located overseas, on RAF Lakenheath, England. The dream of this this event involved the transformation of the school cafeteria into an elegant art show…

  2. Honored Teacher Shows Commitment.

    ERIC Educational Resources Information Center

    Ratte, Kathy

    1987-01-01

    Part of the acceptance speech of the 1985 National Council for the Social Studies Teacher of the Year, this article describes the censorship experience of this honored social studies teacher. The incident involved the showing of a videotape version of the feature film entitled "The Seduction of Joe Tynan." (JDH)

  3. 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.

  4. 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.

  5. Taking in a Show.

    PubMed

    Boden, Timothy W

    2016-01-01

    Many medical practices have cut back on education and staff development expenses, especially those costs associated with conventions and conferences. But there are hard-to-value returns on your investment in these live events--beyond the obvious benefits of acquired knowledge and skills. Major vendors still exhibit their services and wares at many events, and the exhibit hall is a treasure-house of information and resources for the savvy physician or administrator. Make and stick to a purposeful plan to exploit the trade show. You can compare products, gain new insights and ideas, and even negotiate better deals with representatives anxious to realize returns on their exhibition investments. PMID:27249887

  6. Taking in a Show.

    PubMed

    Boden, Timothy W

    2016-01-01

    Many medical practices have cut back on education and staff development expenses, especially those costs associated with conventions and conferences. But there are hard-to-value returns on your investment in these live events--beyond the obvious benefits of acquired knowledge and skills. Major vendors still exhibit their services and wares at many events, and the exhibit hall is a treasure-house of information and resources for the savvy physician or administrator. Make and stick to a purposeful plan to exploit the trade show. You can compare products, gain new insights and ideas, and even negotiate better deals with representatives anxious to realize returns on their exhibition investments.

  7. Obesity in show dogs.

    PubMed

    Corbee, R J

    2013-10-01

    Obesity is an important disease with a growing incidence. Because obesity is related to several other diseases, and decreases life span, it is important to identify the population at risk. Several risk factors for obesity have been described in the literature. A higher incidence of obesity in certain breeds is often suggested. The aim of this study was to determine whether obesity occurs more often in certain breeds. The second aim was to relate the increased prevalence of obesity in certain breeds to the official standards of that breed. To this end, we investigated 1379 dogs of 128 different breeds by determining their body condition score (BCS). Overall, 18.6% of the show dogs had a BCS >5, and 1.1% of the show dogs had a BCS>7. There were significant differences between breeds, which could be correlated to the breed standards. It warrants firm discussions with breeders and judges in order to come to different interpretations of the standards to prevent overweight conditions from being the standard of beauty. PMID:22882163

  8. Methods of forming steel

    DOEpatents

    Branagan, Daniel J.; Burch, Joseph V.

    2001-01-01

    In one aspect, the invention encompasses a method of forming a steel. A metallic glass is formed and at least a portion of the glass is converted to a crystalline steel material having a nanocrystalline scale grain size. In another aspect, the invention encompasses another method of forming a steel. A molten alloy is formed and cooled the alloy at a rate which forms a metallic glass. The metallic glass is devitrified to convert the glass to a crystalline steel material having a nanocrystalline scale grain size. In yet another aspect, the invention encompasses another method of forming a steel. A first metallic glass steel substrate is provided, and a molten alloy is formed over the first metallic glass steel substrate to heat and devitrify at least some of the underlying metallic glass of the substrate.

  9. Not a "reality" show.

    PubMed

    Wrong, Terence; Baumgart, Erica

    2013-01-01

    The authors of the preceding articles raise legitimate questions about patient and staff rights and the unintended consequences of allowing ABC News to film inside teaching hospitals. We explain why we regard their fears as baseless and not supported by what we heard from individuals portrayed in the filming, our decade-long experience making medical documentaries, and the full un-aired context of the scenes shown in the broadcast. The authors don't and can't know what conversations we had, what documents we reviewed, and what protections we put in place in each televised scene. Finally, we hope to correct several misleading examples cited by the authors as well as their offhand mischaracterization of our program as a "reality" show. PMID:23631336

  10. Not a "reality" show.

    PubMed

    Wrong, Terence; Baumgart, Erica

    2013-01-01

    The authors of the preceding articles raise legitimate questions about patient and staff rights and the unintended consequences of allowing ABC News to film inside teaching hospitals. We explain why we regard their fears as baseless and not supported by what we heard from individuals portrayed in the filming, our decade-long experience making medical documentaries, and the full un-aired context of the scenes shown in the broadcast. The authors don't and can't know what conversations we had, what documents we reviewed, and what protections we put in place in each televised scene. Finally, we hope to correct several misleading examples cited by the authors as well as their offhand mischaracterization of our program as a "reality" show.

  11. Public medical shows.

    PubMed

    Walusinski, Olivier

    2014-01-01

    In the second half of the 19th century, Jean-Martin Charcot (1825-1893) became famous for the quality of his teaching and his innovative neurological discoveries, bringing many French and foreign students to Paris. A hunger for recognition, together with progressive and anticlerical ideals, led Charcot to invite writers, journalists, and politicians to his lessons, during which he presented the results of his work on hysteria. These events became public performances, for which physicians and patients were transformed into actors. Major newspapers ran accounts of these consultations, more like theatrical shows in some respects. The resultant enthusiasm prompted other physicians in Paris and throughout France to try and imitate them. We will compare the form and substance of Charcot's lessons with those given by Jules-Bernard Luys (1828-1897), Victor Dumontpallier (1826-1899), Ambroise-Auguste Liébault (1823-1904), Hippolyte Bernheim (1840-1919), Joseph Grasset (1849-1918), and Albert Pitres (1848-1928). We will also note their impact on contemporary cinema and theatre. PMID:25273491

  12. The Great Cometary Show

    NASA Astrophysics Data System (ADS)

    2007-01-01

    its high spatial and spectral resolution, it was possible to zoom into the very heart of this very massive star. In this innermost region, the observations are dominated by the extremely dense stellar wind that totally obscures the underlying central star. The AMBER observations show that this dense stellar wind is not spherically symmetric, but exhibits a clearly elongated structure. Overall, the AMBER observations confirm that the extremely high mass loss of Eta Carinae's massive central star is non-spherical and much stronger along the poles than in the equatorial plane. This is in agreement with theoretical models that predict such an enhanced polar mass-loss in the case of rapidly rotating stars. ESO PR Photo 06c/07 ESO PR Photo 06c/07 RS Ophiuchi in Outburst Several papers from this special feature focus on the later stages in a star's life. One looks at the binary system Gamma 2 Velorum, which contains the closest example of a star known as a Wolf-Rayet. A single AMBER observation allowed the astronomers to separate the spectra of the two components, offering new insights in the modeling of Wolf-Rayet stars, but made it also possible to measure the separation between the two stars. This led to a new determination of the distance of the system, showing that previous estimates were incorrect. The observations also revealed information on the region where the winds from the two stars collide. The famous binary system RS Ophiuchi, an example of a recurrent nova, was observed just 5 days after it was discovered to be in outburst on 12 February 2006, an event that has been expected for 21 years. AMBER was able to detect the extension of the expanding nova emission. These observations show a complex geometry and kinematics, far from the simple interpretation of a spherical fireball in extension. AMBER has detected a high velocity jet probably perpendicular to the orbital plane of the binary system, and allowed a precise and careful study of the wind and the shockwave

  13. Stretched View Showing 'Victoria'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Stretched View Showing 'Victoria'

    This pair of images from the panoramic camera on NASA's Mars Exploration Rover Opportunity served as initial confirmation that the two-year-old rover is within sight of 'Victoria Crater,' which it has been approaching for more than a year. Engineers on the rover team were unsure whether Opportunity would make it as far as Victoria, but scientists hoped for the chance to study such a large crater with their roving geologist. Victoria Crater is 800 meters (nearly half a mile) in diameter, about six times wider than 'Endurance Crater,' where Opportunity spent several months in 2004 examining rock layers affected by ancient water.

    When scientists using orbital data calculated that they should be able to detect Victoria's rim in rover images, they scrutinized frames taken in the direction of the crater by the panoramic camera. To positively characterize the subtle horizon profile of the crater and some of the features leading up to it, researchers created a vertically-stretched image (top) from a mosaic of regular frames from the panoramic camera (bottom), taken on Opportunity's 804th Martian day (April 29, 2006).

    The stretched image makes mild nearby dunes look like more threatening peaks, but that is only a result of the exaggerated vertical dimension. This vertical stretch technique was first applied to Viking Lander 2 panoramas by Philip Stooke, of the University of Western Ontario, Canada, to help locate the lander with respect to orbiter images. Vertically stretching the image allows features to be more readily identified by the Mars Exploration Rover science team.

    The bright white dot near the horizon to the right of center (barely visible without labeling or zoom-in) is thought to be a light-toned outcrop on the far wall of the crater, suggesting that the rover can see over the low rim of Victoria. In figure 1, the northeast and southeast rims are labeled

  14. Mapping the global flow of steel: from steelmaking to end-use goods.

    PubMed

    Cullen, Jonathan M; Allwood, Julian M; Bambach, Margarita D

    2012-12-18

    Our society is addicted to steel. Global demand for steel has risen to 1.4 billion tonnes a year and is set to at least double by 2050, while the steel industry generates nearly a 10th of the world's energy related CO₂ emissions. Meeting our 2050 climate change targets would require a 75% reduction in CO₂ emissions for every tonne of steel produced and finding credible solutions is proving a challenge. The starting point for understanding the environmental impacts of steel production is to accurately map the global steel supply chain and identify the biggest steel flows where actions can be directed to deliver the largest impact. In this paper we present a map of global steel, which for the first time traces steel flows from steelmaking, through casting, forming, and rolling, to the fabrication of final goods. The diagram reveals the relative scale of steel flows and shows where efforts to improve energy and material efficiency should be focused.

  15. Elastic constant versus temperature behavior of three hardened maraging steels

    NASA Technical Reports Server (NTRS)

    Ledbetter, H. M.; Austin, M. W.

    1985-01-01

    Elastic constants of three maraging steels were determined by measuring ultrasonic velocities. Annealed steels show slightly lower bulk moduli and considerably lower shear moduli than hardened steels. All the elastic constants (Young's modulus, shear modulus, bulk modulus and Poisson's ratio) show regular temperature behavior between 76 and 400 K. Young's modulus and the shear modulus increase with increasing yield strength, but the bulk modulus and Poisson's ratio are relatively unchanged. Elastic anisotropy is quite small.

  16. Low-chromium reduced-activation ferritic steels for fusion

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.; Kenik, E.A.

    1996-04-01

    Development of reduced-activation ferritic steels has concentrated on high-chromium (8-10 wt% Cr) steels. However, there are advantages for a low-chromium steel, and initial ORNL studies on reduced-activation steels were on compositions with 2.25 to 12% Cr. Those studies showed an Fe-2.25Cr-2W-0.25V-0.1C (2 1/4Cr-2WV) steel to have the highest strenglth of the steels studied. Although this steel had the best strength, Charpy impact properties were inferior to those of an Fe-9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa) and an Fe-2.25Cr-2W-0.1C (2 1/4Cr-2W) steel. Therefore, further development of the low-chromium Cr-W steels was required. These results indicate that it is possible to develop low-chromium reduced-activation ferritic steels that have tensile and impact properties as good or better than those of high-chromium (7-9% Cr) steels. Further improvement of properties should be possible by optimizing the composition.

  17. Crack stability analysis of low alloy steel primary coolant pipe

    SciTech Connect

    Tanaka, T.; Kameyama, M.; Urabe, Y.

    1997-04-01

    At present, cast duplex stainless steel has been used for the primary coolant piping of PWRs in Japan and joints of dissimilar material have been applied for welding to reactor vessels and steam generators. For the primary coolant piping of the next APWR plants, application of low alloy steel that results in designing main loops with the same material is being studied. It means that there is no need to weld low alloy steel with stainless steel and that makes it possible to reduce the welding length. Attenuation of Ultra Sonic Wave Intensity is lower for low alloy steel than for stainless steel and they have advantageous inspection characteristics. In addition to that, the thermal expansion rate is smaller for low alloy steel than for stainless steel. In consideration of the above features of low alloy steel, the overall reliability of primary coolant piping is expected to be improved. Therefore, for the evaluation of crack stability of low alloy steel piping to be applied for primary loops, elastic-plastic future mechanics analysis was performed by means of a three-dimensioned FEM. The evaluation results for the low alloy steel pipings show that cracks will not grow into unstable fractures under maximum design load conditions, even when such a circumferential crack is assumed to be 6 times the size of the wall thickness.

  18. Thermal treatment of dissimilar steels' welded joints

    NASA Astrophysics Data System (ADS)

    Nikulina, A. A.; Denisova, A. S.; Gradusov, I. N.; Ryabinkina, P. A.; Rushkovets, M. V.

    2016-04-01

    In this paper combinations of chrome-nickel steel and high-carbon steel, produced by flash butt welding after heat treatment, are investigated. Light and electron microscopic studies show that the welded joints after heat treatment have a complex structure consisting of several phases as initial welded joints. A martensite structure in welded joints after thermal treatment at 300... 800 °C has been found.

  19. 2169 steel waveform experiments.

    SciTech Connect

    Furnish, Michael David; Alexander, C. Scott; Reinhart, William Dodd; Brown, Justin L.

    2012-11-01

    In support of LLNL efforts to develop multiscale models of a variety of materials, we have performed a set of eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn, balance predominantly Fe). These experiments provided carefully controlled shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were included in this experiment set to increase the utility of the data set, as were samples ranging in thickness from 1 to 5 mm. Target physical phenomena included the elastic/plastic transition (Hugoniot elastic limit), the Hugoniot, any phase transition phenomena, and the release path (windowed and free-surface). The Hugoniot was found to be nearly linear, with no indications of the Fe phase transition. Releases were non-hysteretic, and relatively consistent between 3- and 5-mmthick samples (the 3 mm samples giving slightly lower wavespeeds on release). Reshock tests with explosively welded impactors produced clean results; those with glue bonds showed transient releases prior to the arrival of the reshock, reducing their usefulness for deriving strength information. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allows release information to be determined from these free surface samples. The sample strength appears to increase with stress from ~1 GPa to ~ 3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model.

  20. Weld overlay cladding with iron aluminides

    SciTech Connect

    Goodwin, G.M.

    1995-08-01

    The hot and cold cracking tendencies of some early iron aluminide alloy compositions have limited their use in applications where good weldability is required. Using hot crack testing techniques invented at ORNL, and experimental determinations of preheat and postweld heat treatment needed to avoid cold cracking, we have developed iron aluminide filler metal compositions which can be successfully used to weld overlay clad various substrate materials, including 9Cr-1Mo steel, 2-1/4Cr-1Mo steel, and 300-series austenitic stainless steels. Dilution must be carefully controlled to avoid crack-sensitive deposit compositions. The technique used to produce the current filler metal compositions is aspiration-casting, i.e. drawing the liquid from the melt into glass rods. Future development efforts will involve fabrication of composite wires of similar compositions to permit mechanized gas tungsten arc (GTA) and/or gas metal arc (GMA) welding.

  1. Corrosion Behavior and Durability of Low-Alloy Steel Rebars in Marine Environment

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Cheng, Xuequn; Li, Xiaogang; Yue, Pan; Li, Jun

    2016-10-01

    The corrosion resistance of Cr-modified low-alloy steels and HRB400 carbon steel was estimated using the open-circuit potential, potentiodynamic polarization, electrochemical impedance spectroscopic, and weight loss methods in simulated concrete pore solution. Results show that Cr-modified steels exhibit a higher corrosion resistance with a higher critical chloride level (CTL), lower corrosion current density, and higher impedance than carbon steel. The CTL of the steels significantly reduces with increasing temperature. Weight loss measurement shows that the Cr-modified steels exhibit low corrosion rates and small corrosion pitting. The primary constituents of the corrosion scales are Fe2O3, Fe3O4, β-FeOOH, γ-FeOOH, and α-FeOOH. A large amount of α-FeOOH could be detected in the Cr-modified steel corrosion products. Moreover, the Cr-modified steels demonstrate a higher durability than HRB400 carbon steel.

  2. 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.

  3. Solid-state joining of ultrahigh carbon steels

    SciTech Connect

    Sunwoo, A.J.

    1993-04-22

    A joining study of these steels was initiated to determine the feasibility of using ultrahigh carbon steels in structural applications. The high carbon content (1.5 wt%) in these steels and the desire to maintain the superplastic microstructure limit the use of conventional arc-welding processes. We chose two solid-state joining processes: diffusion bonding and inertia friction welding. Preliminary results show that sound bonds can be obtained with tensile properties nearly equal to those of the base metal. Of three UHC steels bonded by both inertia-friction welding and diffusion- bonding processes, the one with the lowest aluminum content had the best overall properties. Diffusion bonding with a nickel interlayer showed the most promising results for the UHC steel containing 1.6 wt% aluminum. The properties of inertia-friction-welded steels can be improved by a post-weld heat treatment.

  4. Modern Steel Framed Schools.

    ERIC Educational Resources Information Center

    American Inst. of Steel Construction, Inc., New York, NY.

    In view of the cost of structural framing for school buildings, ten steel-framed schools are examined to review the economical advantages of steel for school construction. These schools do not resemble each other in size, shape, arrangement or unit cost; some are original in concept and architecture, and others are conservative. Cost and…

  5. Steel Industry Wastes.

    ERIC Educational Resources Information Center

    Schmidtke, N. W.; Averill, D. W.

    1978-01-01

    Presents a literature review of wastes from steel industry, covering publications of 1976-77. This review covers: (1) coke production; (2) iron and steel production; (3) rolling operations; and (4) surface treatment. A list of 133 references is also presented. (NM)

  6. The Steel Band.

    ERIC Educational Resources Information Center

    Weil, Bruce

    1996-01-01

    Describes studying the steel drum, an import from Trinidad, as an instrument of intellectual growth. Describes how developing a steel drum band provided Montessori middle school students the opportunity to experience some important feelings necessary to emotional growth during this difficult age: competence, usefulness, independence, and…

  7. EAST ELEVATION, LTV STEEL (FORMERLY REPUBLIC STEEL), 8" BAR MILL, ...

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

    EAST ELEVATION, LTV STEEL (FORMERLY REPUBLIC STEEL), 8" BAR MILL, BUFFALO PLANT. VIEW LOOKING SOUTHWEST FROM ROLL SHOP. 8" BAR MILL DESIGNED AND BUILT BY DONNER STEEL CO. (PREDECESSOR OF REPUBLIC), 1919-1920. FOR DESCRIPTION OF ORIGINAL MILL SEE "IRON AGE", 116\\4 (23 JULY 1925): 201-204. - LTV Steel, 8-inch Bar Mill, Buffalo Plant, Buffalo, Erie County, NY

  8. INTERIOR VIEW SHOWING QBOP FURNACE IN BLOW. OXYGEN AND NATURAL ...

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

    INTERIOR VIEW SHOWING Q-BOP FURNACE IN BLOW. OXYGEN AND NATURAL GAS ARE BLOWN INTO THE FURNACE THROUGH THE TUYERES TO CHARGE 460,000 LBS. OF HOT METAL, 100,000 LBS. OF SCRAP WITH 30,000 LBS. OF LIME. BLOW TIME IS 16 MINUTES. THE TIME TO BLOW AND TAP THE FURNACES OF THE RESULTING 205,000 TONS OF STEEL AND SLAG IS 35 MINUTES. - U.S. Steel, Fairfield Works, Q-Bop Furnace, North of Valley Road & West of Ensley, Pleasant Grove Road, Fairfield, Jefferson County, AL

  9. 10. VIEW SHOWING THE ARCH FORMS. THE INTRADOS FORM IS ...

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

    10. VIEW SHOWING THE ARCH FORMS. THE INTRADOS FORM IS COMMONLY LIFTED 3 TO 4 DAYS AFTER POURING. REINFORCING STEEL IS THEN PLACED AND THE EXTRADOS FORM RAISED TO POSITION. THE OPERATING OF MOVING FORMS, PLACING STEEL AND CONCRETE FOR EACH ARCH LIFT REQUIRES, ON AVERAGE, EIGHT DAYS. NOTE THE TWO LINES OF WATER PIPE ON THE EXTRADOS FORM. THESE PIPES ARE FILLED WITH SPRAY NOZZLES WHICH ARE IN PRACTICALLY CONTINUOUS OPERATION EXCEPT WHEN WORK IS BEING DONE ON THE FORMS. August 9, 1938 - Bartlett Dam, Verde River, Phoenix, Maricopa County, AZ

  10. 3. NORTH ELEVATION OF THE HOT BAY, SHOWING RAILROAD TRACKS ...

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

    3. NORTH ELEVATION OF THE HOT BAY, SHOWING RAILROAD TRACKS LEADING TO THE MASSIVE STEEL-LINED CONCRETE ENTRANCE DOOR. PART OF THE INTRICATE HVAC SYSTEM IS WEST (RIGHT) OF THE DOOR. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  11. Detail of wharf A timber framing, showing piers and pier ...

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

    Detail of wharf A timber framing, showing piers and pier caps or plates stepping down for a sloped launching deck, now built-up for a flat deck, interior of sheet steel bulkhead is visible at wharf edge - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  12. NORTH AND WEST ELEVATIONS, SHOWING CA. 1960 OPEN STORAGE STRUCTURE, ...

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

    NORTH AND WEST ELEVATIONS, SHOWING CA. 1960 OPEN STORAGE STRUCTURE, BRICK-WALLED NORTH PART, AND CORRUGATED-STEEL SOUTH PART, CAMERA FACING SOUTHEAST. - New Haven Rail Yard, Work Equipment Shop, Vicinity of Cedar & Lamberton Streets, New Haven, New Haven County, CT

  13. Detail of old rain shed (Building No. 43) showing truss ...

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

    Detail of old rain shed (Building No. 43) showing truss type B at wall post. New aluminum roofing seen in comparison with older galvanized steel siding. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  14. VIEW FROM THE EAST, SHOWING THE STOCK BINS IN THE ...

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

    VIEW FROM THE EAST, SHOWING THE STOCK BINS IN THE FOREGROUND, THE #1 BLAST FURNACE ON THE RIGHT, STOVES IN THE CENTER, AND THE #2 BLAST FURNACE ON THE LEFT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  15. VIEW OF CENTRAL COMPLEX FROM THE EAST, SHOWING THE #1 ...

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

    VIEW OF CENTRAL COMPLEX FROM THE EAST, SHOWING THE #1 BLAST FURNACE ON THE RIGHT, THE #2 BLAST FURNACE ON THE LEFT, AND THE BOILERS AND STOVES IN THE CENTER. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  16. 126. EXTERIOR VIEW, LOOKING NORTH, SHOWING CAST SHED NO. 2, ...

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

    126. EXTERIOR VIEW, LOOKING NORTH, SHOWING CAST SHED NO. 2, FURNACE NO. 2, STOVES, POWER HOUSE, STACKS, FURNACE NO. 1 CAST SHED. FURNACE NO. 2 IS IN PROCESS OF RESTORATION. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  17. 11. DETAIL: OBLIQUE VIEW FROM SOUTHWEST OF TYPICAL SPAN SHOWING ...

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

    11. DETAIL: OBLIQUE VIEW FROM SOUTHWEST OF TYPICAL SPAN SHOWING ART DECO RELIEFS AND REMAINS OF BRACKETS FOR SUPPORTING STEEL SIDEWALKS. - Puente de la Marina, San Lorenzo-Florida & Cerro Gordo Neighborhoods, spanning Rio Grande de Loiza River at Narciso Varona-Suarez Street, San Lorenzo, San Lorenzo Municipio, PR

  18. VIEW OF THE #2 BLAST FURNACE FROM THE EAST, SHOWING ...

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

    VIEW OF THE #2 BLAST FURNACE FROM THE EAST, SHOWING SKIP HOIST, DUST CATCHER AND STOCK BINS IN THE FOREGROUND. #2 CASTING SHED IS TO THE LEFT, HOT BLAST MAIN IS ON THE RIGHT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  19. 77. Detail view looking east showing Dovel horizontal gas washer ...

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

    77. Detail view looking east showing Dovel horizontal gas washer in foreground, Rust Co. boilers and blowing engine house at left, and Babcock & Wilcox type boilers at right. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  20. 76. General view looking east showing Rust Co. boiler stacks ...

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

    76. General view looking east showing Rust Co. boiler stacks at left, Babcock & Wilcox type boiler stacks at right, Dovel horizontal gas washer in foreground, and No. 1 Furnace in distance. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  1. 92. View of east facade of powerhouse, showing rear door ...

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

    92. View of east facade of powerhouse, showing rear door of the building; the steel tanks adjacent to the powerhouse are surge tanks, each penstock has two surge tanks; looking west. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  2. 8. DETAIL OF UNITEDTOD TWINTANDEM STEAM ENGINE, SHOWING CYLINDER AND ...

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

    8. DETAIL OF UNITED-TOD TWIN-TANDEM STEAM ENGINE, SHOWING CYLINDER AND CROSS HEAD OF PISTON AT THE HIGH-PRESSURE SIDE OF ENGINE. - Republic Iron & Steel Company, Youngstown Works, Blooming Mill & Blooming Mill Engines, North of Poland Avenue, Youngstown, Mahoning County, OH

  3. 7. DETAIL OF UNITEDTOD TWINTANDEM STEAM ENGINE, SHOWING CYLINDER AND ...

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

    7. DETAIL OF UNITED-TOD TWIN-TANDEM STEAM ENGINE, SHOWING CYLINDER AND CROSS HEAD OF PISTON AT THE LOW PRESSURE SIDE OF ENGINE. - Republic Iron & Steel Company, Youngstown Works, Blooming Mill & Blooming Mill Engines, North of Poland Avenue, Youngstown, Mahoning County, OH

  4. INTERIOR VIEW SHOWING DISPLAY OF INSIDE OF BLAST FURNACE AND ...

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

    INTERIOR VIEW SHOWING DISPLAY OF INSIDE OF BLAST FURNACE AND MACHINERY AND ARTIFACTS INCLUDING A STEAM ENGINE HUB MADE AT THE BRIERFIELD ROLLING MILL (INSCRIBED C.C. HUCKABEE AND DATED 1863) AND OTHER STEAM ENGINES. - Iron & Steel Museum of Alabama, 12632 Confederate Pkwy., Bucksville, Tuscaloosa County, AL

  5. 11. DETAIL OF UNITEDTOD TWINTANDEM STEAM ENGINE, SHOWING HIGHPRESSURE CYLINDER ...

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

    11. DETAIL OF UNITED-TOD TWIN-TANDEM STEAM ENGINE, SHOWING HIGH-PRESSURE CYLINDER AND VALVE, AND LUBRICATING EQUIPMENT FOR ENGINE. - Republic Iron & Steel Company, Youngstown Works, Blooming Mill & Blooming Mill Engines, North of Poland Avenue, Youngstown, Mahoning County, OH

  6. 88. View inside No. 2 turboblower house looking east showing ...

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

    88. View inside No. 2 turbo-blower house looking east showing 1951 Ingersoll-Rand turbo-blower with engine casing removed. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  7. 87. View inside No. 2 turboblower house looking west showing ...

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

    87. View inside No. 2 turbo-blower house looking west showing 1951 Ingersoll-Rand turbo-blower with engine casing removed. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  8. 5. VIEW OF THE EASTERN BRIDGE ELEVATION, SHOWING CENTRAL CUT ...

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

    5. VIEW OF THE EASTERN BRIDGE ELEVATION, SHOWING CENTRAL CUT AND MORTARED STONE PIER AND ASSOCIATED STEEL SUPERSTRUCTURE (CENTER), AND CANTILEVERED NORTHERN TRUSS SECTION (RIGHT). FACING NORTHWEST. - Coverts Crossing Bridge, Spanning Mahoning River along Township Route 372 (Covert Road), New Castle, Lawrence County, PA

  9. 1. Overall view, showing Mispillion Lighthouse (East Elevation) in its ...

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

    1. Overall view, showing Mispillion Lighthouse (East Elevation) in its context Note: Steel skeleton beacon tower on left. - Mispillion Lighthouse, South bank of Mispillion River at its confluence with Delaware River at northeast end of County Road 203, 7 miles east of Milford, Milford, Sussex County, DE

  10. 10. Copy of a photograph taken c. 1910 showing American ...

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

    10. Copy of a photograph taken c. 1910 showing American Steel & Wire's campaign for safety on the Job: 'The Fence of Safety Around the Happy Home. . . Every Broken Picket Means One Lost Time Accident.' Photo courtesy Ralph A. Dise, Cleveland Heights, Ohio. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  11. Detail of old rain shed (Building No. 43) showing northeast ...

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

    Detail of old rain shed (Building No. 43) showing northeast wall and gutter boxes. Two 750,000 gallon steel tanks at right (T19 in foreground with T18 behind). - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  12. 2. SOUTH FACADE OF THE 48' PLATE MILL BUILDINGS SHOWING, ...

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

    2. SOUTH FACADE OF THE 48' PLATE MILL BUILDINGS SHOWING, LEFT TO RIGHT, TWO FURNACE BAYS, THE MAIN MILL BUILDINGS, AND THE REMAINS OF THE SHIPPING BUILDING. - U.S. Steel Homestead Works, 48" Plate Mill, Along Monongahela River, Homestead, Allegheny County, PA

  13. 93. View showing erection traveler erecting 190 foot span over ...

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

    93. View showing erection traveler erecting 190 foot span over Southern Pacific Company's main line track. This is the last span of the steel approach to the main bridge spans. - Carquinez Bridge, Spanning Carquinez Strait at Interstate 80, Vallejo, Solano County, CA

  14. 2. Building 3 north elevation showing stack, Building 4 on ...

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

    2. Building 3 north elevation showing stack, Building 4 on right, Building 15 with steel water tower and hopper behind. View looking SSW. - John & James Dobson Carpet Mill (West Parcel), Building No. 3, 4041-4055 Ridge Avenue, Philadelphia, Philadelphia County, PA

  15. GENERAL VIEW OF CENTRAL COMPLEX SHOWING STICK BINS FOR RAW ...

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

    GENERAL VIEW OF CENTRAL COMPLEX SHOWING STICK BINS FOR RAW MATERIALS IN FOREGROUND, FOUR LARGE BOILER UNITS, AND STOVES AND THE #2 BLAST FURNACE WITH SKIP HOIST IN BACKGROUND. VIEW FROM THE EAST. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  16. GENERAL VIEW FROM THE SOUTH, SHOWING CENTRAL COMPLEX WITH THE ...

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

    GENERAL VIEW FROM THE SOUTH, SHOWING CENTRAL COMPLEX WITH THE STOCK BINS FOR RAW MATERIALS IN THE FOREGROUND, FOUR LARGE BOILER UNITS AND STOVE'S AND THE #1 BLAST FURNACE WITH SKIP HOIST IN THE BACKGROUND. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  17. GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 CASTING SHED ...

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

    GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 CASTING SHED IN THE FOREGROUND WITH THE STOVES AND TOP WORKS OF THE #1 FURNACE IN THE BACKGROUND. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  18. GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 BLAST FURNACE ...

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

    GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 BLAST FURNACE IN THE RIGHT; THE CENTRAL COMPLEX WITH STOVES IN THE CENTER. ELECTRICAL POWER HOUSE IS ON THE LEFT BEYOND THE CONVEYOR LIFT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  19. 116. View looking southeast at stoves 2124 showing hot blast ...

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

    116. View looking southeast at stoves 21-24 showing hot blast main to No. 2 Furnace leading off to the right and gas main running in front of stoves. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  20. 4. VIEW SOUTH SHOWING AQUEDUCT PRISM. NOTE 1920 TIMBER AND ...

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

    4. VIEW SOUTH SHOWING AQUEDUCT PRISM. NOTE 1920 TIMBER AND CONCRETE FLOORING SYSTEM, POCKETS FOR VERTICAL POSTS AND BRIDGING, STEEL BRACES ADDED BY THE NATIONAL PARK SERVICE CIRCA 1962. - Chesapeake & Ohio Canal, Conococheague Creek Aqueduct, Milepost 99.80, Williamsport, Washington County, MD

  1. Exterior view along the west side, showing the alternating wood ...

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

    Exterior view along the west side, showing the alternating wood and steel ceiling beams and metal sash windows, view facing northeast - U.S. Marine Corps Base Hawaii, Kaneohe Bay, Warehouse 250, Aviation Storehouse, C Street between Fifth & Sixth Streets, Kaneohe, Honolulu County, HI

  2. 3. EXTERIOR OF FRONT ENTRY SHOWING GABLE OVER RECESSED PORCH ...

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

    3. EXTERIOR OF FRONT ENTRY SHOWING GABLE OVER RECESSED PORCH WITH RUSTIC STYLE DECORATIVE TREATMENT. WELDED STEEL PORCH RAILING ADDED IN 1972 IS VISIBLE AT PHOTO CENTER. VIEW TO SOUTHWEST. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  3. 19. DETAIL VIEW SHOWING POINT OF CONNECTION OF SWAY BRACING ...

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

    19. DETAIL VIEW SHOWING POINT OF CONNECTION OF SWAY BRACING TO UPSTREAM ARCH RIB AT SPRING POINT FROM SOUTH ABUTMENT, LOOKING EAST-NORTHEAST. NOTE CRACK VISIBLE NEAR TOP OF SWAY BRACING AT LEFT CENTER, PROBABLY DUE TO RUST JACKING OF REINFORCING STEEL - Chili Bar Bridge, Spanning South Fork of American River at State Highway 193, Placerville, El Dorado County, CA

  4. VIEW FROM THE EAST, SHOWING THE #2 BLAST FURNACE WITH ...

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

    VIEW FROM THE EAST, SHOWING THE #2 BLAST FURNACE WITH SKIP HOIST, DUST CATCHER AND STOCK BINS FOR RAW MATERIALS IN THE FOREGROUND. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  5. Welding of high chromium steels

    NASA Technical Reports Server (NTRS)

    Miller, W B

    1928-01-01

    A brief description is given of different groups of high chromium steels (rustless iron and stainless steels) according to their composition and more generally accepted names. The welding procedure for a given group will be much the same regardless of the slight variations in chemical composition which may exist within a certain group. Information is given for the tensile properties (yield point and ultimate strength) of metal sheets and welds before and after annealing on coupons one and one-half inches wide. Since welds in rustless iron containing 16 to 18 percent chromium and 7 to 12 percent nickel show the best combination of strength and ductility in the 'as welded' or annealed condition, it is considered the best alloy to use for welded construction.

  6. Shock Hugoniot of 1215 steel

    NASA Astrophysics Data System (ADS)

    Brar, N. S.; Rosenberg, Z.

    1996-05-01

    1215 steel is almost pure iron with 0.1 percent or less carbon. Information pertaining to deformation of this material under shock loading is useful to simulate penetration of projectiles of different shapes, such as fragments or rods, in propellants storage containments made from almost pure iron. In this paper we present the dynamic response of 1215 steel to shock wave loading to 30 GPa. Manganin gauges were used to record the stress wave profiles in these experiments. The Hugoniot data in the stress-particle velocity plane was obtained to 30 GPa. Hugoniot elastic limit was found to be 1.37±0.05 GPa. Phase transformation (α-ɛ) takes place at about 13.2±0.2 GPa, which agrees with the value determined by Barker and Hollenbach using VISAR. Hugoniot does not show any softening at stresses below 13 GPa.

  7. Aluminide Coatings for Power-Generation Applications

    SciTech Connect

    Zhang, Y

    2003-11-17

    Aluminide coatings are of interest for many high temperature applications because of the possibility of improving the oxidation of structural alloys by forming a protective external alumina scale. In order to develop a comprehensive lifetime evaluation approach for aluminide coatings used in fossil energy systems, some of the important issues have been addressed in this report for aluminide coatings on Fe-based alloys (Task I) and on Ni-based alloys (Task II). In Task I, the oxidation behavior of iron aluminide coatings synthesized by chemical vapor deposition (CVD) was studied in air + 10vol.% H{sub 2}O in the temperature range of 700-800 C and the interdiffusion behavior between the coating and substrate was investigated in air at 500-800 C. Commercial ferritic (Fe-9Cr-1Mo) and type 304L (Fe-18Cr-9Ni, nominally) austenitic stainless steels were used as the substrates. For the oxidation study, the as-deposited coating consisted of a thin (<5 {micro}m), Al-rich outer layer above a thicker (30-50 {micro}m), lower Al inner layer. The specimens were cycled to 1000 1-h cycles at 700 C and 500 1-h cycles at 800 C, respectively. The CVD coating specimens showed excellent performance in the water vapor environment at both temperatures, while the uncoated alloys were severely attacked. These results suggest that an aluminide coating can substantially improve resistance to water vapor attack under these conditions. For the interdiffusion study, the ferritic and austenitic steels were coated with relatively thicker aluminide coatings consisting of a 20-25 {micro}m outer layer and a 150-250 {micro}m inner layer. The composition profiles before and after interdiffusion testing (up to 5,000h) were measured by electron probe microanalysis (EPMA). The decrease of the Al content at the coating surface was not significant after extended diffusion times ({le} 5,000h) at temperatures {le} 700 C. More interdiffusion occurred at 800 C in coatings on both Fe- 9Cr-1Mo and 304L alloys; a

  8. Nuclear transmutation in steels

    NASA Astrophysics Data System (ADS)

    Belozerova, A. R.; Shimanskii, G. A.; Belozerov, S. V.

    2009-05-01

    The investigations of the effects of nuclear transmutation in steels that are widely used in nuclear power and research reactors and in steels that are planned for the application in thermonuclear fusion plants, which are employed under the conditions of a prolonged action of neutron irradiation with different spectra, made it possible to study the effects of changes in the isotopic and chemical composition on the tendency of changes in the structural stability of these steels. For the computations of nuclear transmutation in steels, we used a program complex we have previously developed on the basis of algorithms for constructing branched block-type diagrams of nuclide transformations and for locally and globally optimizing these diagrams with the purpose of minimizing systematic errors in the calculation of nuclear transmutation. The dependences obtained were applied onto a Schaeffler diagram for steels used for structural elements of reactors. For the irradiation in fission reactors, we observed only a weak influence of the effects of nuclear transmutation in steels on their structural stability. On the contrary, in the case of irradiation with fusion neutrons, a strong influence of the effects of nuclear transmutation in steels on their structural stability has been noted.

  9. Irradiation Assisted Grain Boundary Segregation in Steels

    SciTech Connect

    Lu, Zheng; Faulkner, Roy G.

    2008-07-01

    The understanding of radiation-induced grain boundary segregation (RIS) has considerably improved over the past decade. New models have been introduced and much effort has been devoted to obtaining comprehensive information on segregation from the literature. Analytical techniques have also improved so that chemical analysis of layers 1 nm thick is almost routine. This invited paper will review the major methods used currently for RIS prediction: namely, Rate Theory, Inverse Kirkendall, and Solute Drag approaches. A summary is made of the available data on phosphorus RIS in reactor pressure vessel (RPV) steels. This will be discussed in the light of the predictions of the various models in an effort to show which models are the most reliable and easy to use for forecasting P segregation behaviour in steels. A consequence of RIS in RPV steels is a radiation induced shift in the ductile to brittle transition temperature (DBTT). It will be shown how it is possible to relate radiation-induced P segregation levels to DBTT shift. Examples of this exercise will be given for RPV steels and for ferritic steels being considered for first wall fusion applications. Cr RIS in high alloy stainless steels and associated irradiation-assisted stress corrosion cracking (IASCC) will be briefly discussed. (authors)

  10. Utilization of structural steel in buildings

    PubMed Central

    Moynihan, Muiris C.; Allwood, Julian M.

    2014-01-01

    Over one-quarter of steel produced annually is used in the construction of buildings. Making this steel causes carbon dioxide emissions, which climate change experts recommend be reduced by half in the next 37 years. One option to achieve this is to design and build more efficiently, still delivering the same service from buildings but using less steel to do so. To estimate how much steel could be saved from this option, 23 steel-framed building designs are studied, sourced from leading UK engineering firms. The utilization of each beam is found and buildings are analysed to find patterns. The results for over 10 000 beams show that average utilization is below 50% of their capacity. The primary reason for this low value is ‘rationalization’—providing extra material to reduce labour costs. By designing for minimum material rather than minimum cost, steel use in buildings could be drastically reduced, leading to an equivalent reduction in ‘embodied’ carbon emissions. PMID:25104911

  11. 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.

  12. A study of Damascus steel

    SciTech Connect

    Berge, P.

    1995-02-16

    The Damascus sword has been an article of fascination for many years to blade collectors and metallurgists alike. The blades were given their name by Europeans who encountered these blades which originated from Damascus, Syria. They are best known for the appearance of the blade face. Genuine Damascus blades show swirling patterns of alternating light and dark regions which are due to the microstructure of the steel. The microstructure consists of arrays of well rounded cementite patterns in a matrix of either pearlite, bainite, or martensite. When this structure is etched the matrix will turn dark leaving the cementite particles light. Although many blades were produced over the centuries, while some of the process is known the making of a genuine Damascus blade today is generally considered a lost art. Many scientists have studied the subject in an attempt to understand the complex process by which the clustered arrays of cementite particles develop in the steel blades. The most prominent theories to date are presented in the General Introduction to this thesis. The thesis is divided into four main parts. In the first part, four proposed mechanisms of cementite cluster sheet formation as they relate to the banding theory are introduced. Experiments to investigate these mechanisms are presented. In Part II, collaborative research focused on the methodology of the reconstructed process for making Damascus steel is presented. In the third part, a study into the graphitization of the reconstructed blades is presented. In Part IV, experimental attempts at producing Damascus steel ingots in the laboratory are presented.

  13. Conducting polymers and corrosion: Polyaniline on steel

    SciTech Connect

    Tallman, D.E.; Pae, Y.; Bierwagen, G.P.

    1999-08-01

    Polyaniline-coated steel panels were studied by electrochemical impedance spectroscopy (EIS) and electrochemical noise methods (ENM). EIS data for the polyaniline sample was obtained for increasing time of immersion. An increase in charge-transfer resistance (R{sub ct}) with immersion time was observed. ENM data showed that active electrochemical changes occurred during the early stages of immersion. The mean current from ENM exhibited a rather large oscillatory behavior during early stages of immersion, and the mean potential from ENM displayed a tendency toward positive values. Noise resistance (R{sub n}) values also showed initial oscillatory fluctuations, with values that reflected a poor barrier property for polyaniline coating. Tafel plots showed a lower corrosion rate and a more noble corrosion potential for the polyaniline-coated sample as compared to a bare steel sample. Electrochemical data confirmed that significant interactions between the polyaniline and steel occurred during he first 5 days of immersion, but that a continuing interaction occurred throughout the entire immersion period. EIS of a polyaniline/epoxy two-coated system on steel also was carried out. Performance of the polyaniline/epoxy system was superior to that of bare steel coated with epoxy alone.

  14. Glass Stronger than Steel

    DOE R&D Accomplishments Database

    Yarris, Lynn

    2011-03-28

    A new type of damage-tolerant metallic glass, demonstrating a strength and toughness beyond that of steel or any other known material, has been developed and tested by a collaboration of researchers from Berkeley Lab and Caltech.

  15. Life after Steel

    ERIC Educational Resources Information Center

    Mangan, Katherine

    2013-01-01

    Bobby Curran grew up in a working-class neighborhood in Baltimore, finished high school, and followed his grandfather's steel-toed bootprints straight to Sparrows Point, a 3,000-acre sprawl of industry on the Chesapeake Bay. College was not part of the plan. A gritty but well-paying job at the RG Steel plant was Mr. Curran's ticket to a secure…

  16. 1. Copy of Drawing, 'American Steel & Wire Co., Central ...

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

    1. Copy of Drawing, 'American Steel & Wire Co., Central Furnace Works -- Sketch of Plant Showing Tracks & Buildings, 1913, Revised 3/10/31.' Drawing courtesy United States Steel Corporation, Lorain, Ohio. Credit Berni Rich, Score Photographs, August 1979, for photos 1 through 4 and 7 through 11. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  17. 2. Copy of Drawing, 'American Steel & Wire Company, Central ...

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

    2. Copy of Drawing, 'American Steel & Wire Company, Central Furnaces & Docks, General Plan of Works Showing Trestle, 1-3-39.' Drawing courtesy of United States Steel Corporation, Lorain, Ohio. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  18. EMPLACEMENT DRIFT INVERT-LOW STEEL EVALUATION

    SciTech Connect

    M. E. Taylor and D. H. Tang

    2000-09-29

    This technical report evaluates and develops options for reducing the amount of steel in the emplacement drift invert. Concepts developed in the ''Invert Configuration and Drip Shield Interface'' were evaluated to determine material properties required for the proposed invert concepts. Project requirements documents prescribe the use of a carbon steel frame for the invert with a granular material of crushed tuff as ballast. The ''Invert Configuration and Drip Shield Interface'' developed three concepts: (1) All-Ballast Invert; (2) Modified Steel Invert with Ballast; and (3) Steel Tie with Ballast Invert. Analysis of the steel frame members, runway beams, and guide beams, for the modified steel invert with ballast, decreased the quantity of steel in the emplacement drift invert, however a substantial steel support frame for the gantry and waste package/pallet assembly is still required. Use of one of the other two concepts appears to be an alternative to the steel frame and each of the concepts uses considerably less steel materials. Analysis of the steel tie with ballast invert shows that the bearing pressure on the ballast under the single steel tie, C 9 x 20, loaded with the waste package/pallet assembly, drip shield, and backfill exceeds the upper bound of the allowable bearing capacity for tuff used in this study. The single tie, C 10 x 20, will also fail for the same loading condition except for the tie length of 4.2 meters and longer. Analysis also shows that with two ties, C 9 or 10 x 20's, the average ballast pressure is less than the allowable bearing capacity. Distributing the waste package/pallet, drip shield, and backfill loads to two steel ties reduces the contact bearing pressure. Modifying the emplacement pallet end beams to a greater width, reducing the tie spacing, and increasing the width of the ties would ensure that the pallet beams are always supported by two steel ties. Further analysis is required to determine compatible tie size and spacing

  19. Waste product profile: Steel cans

    SciTech Connect

    Miller, C.

    1996-07-01

    Steel cans are made from tinplate steel, which is produced in basic oxygen furnaces. A thin layer of tin is applied to the can`s inner and outer surfaces to prevent rusting and protect food and beverage flavors. As a result, steel cans are often called tin cans. Steel mills are the largest market for steel cans. Integrated mills use the basic oxygen process to manufacture tinplate, appliances, car bodies, and steel framing. Electric arc furnaces use 100% scrap to produce steel shapes such as railroad ties and bridge spans. Electric arc furnaces are more geographically diverse and tend to have smaller capacities than basic oxygen furnaces. Detinners remove the tin from steel cans for resale to tin using industries. Continued decreases in the amount of tin used in steel cans has lessened the importance of this market. Foundries use scrap as a raw material in making castings and molds for industrial users.

  20. 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.

  1. 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

  2. Stainless steel leaches nickel and chromium into foods during cooking.

    PubMed

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

    2013-10-01

    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 2-20 h, 10 consecutive cooking cycles, and four commercial tomato sauces. After a simulated cooking process, samples were analyzed by ICP-MS for Ni and Cr. After 6 h 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, although 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.

  3. Plan Showing Cross Bracing Under Upper Stringers, Typical Section Showing ...

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

    Plan Showing Cross Bracing Under Upper Stringers, Typical Section Showing End Framing, Plan Showing Cross Bracing Under Lower Stringers, End Elevation - Covered Bridge, Spanning Contoocook River, Hopkinton, Merrimack County, NH

  4. Profiles in garbage: Steel cans

    SciTech Connect

    Miller, C.

    1998-02-01

    Steel mills are the largest market for steel cans. Integrated mills use the basic oxygen process to manufacture tinplate, appliances, car bodies, and steel framing. Electric arc furnaces use 100% scrap to produce steel shapes such as railroad ties and bridge spans. Electric arc furnaces are more geographically diverse and tend to have smaller capacities than basic oxygen furnaces. Detinners remove the tin from steel cans for resale to tin using industries. With less tin use in steel cans, the importance of the detinning market has declined substantially. Foundries use scrap as a raw material in making castings and molds for industrial users.

  5. 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.

  6. View northwest, wharf A, sheet steel bulkhead, steel lift tower ...

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

    View northwest, wharf A, sheet steel bulkhead, steel lift tower - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  7. 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.

  8. Antibacterial activity against Porphyromonas gingivalis and biological characteristics of antibacterial stainless steel.

    PubMed

    Zhang, Dan; Ren, Ling; Zhang, Yang; Xue, Nan; Yang, Ke; Zhong, Ming

    2013-05-01

    To evaluate the possibility of an alternative to the traditional orthodontic stainless steel implants, the antibacterial activity against Porphyromonas gingivalis (P. gingivalis) and the related cytotoxicity of a type 304 Cu bearing antibacterial stainless steel were studied. The results indicated that the antibacterial stainless steel showed excellent antibacterial property against P. gingivalis, compared with the control steel (a purchased medical grade 304 stainless steel). Compared to the control steel, there were fewer bacteria on the surface of the antibacterial stainless steel, with significant difference in morphology. The cytotoxicities of the antibacterial stainless steel to both MG-63 and KB cells were all grade 1, the same as those of the control steel. There were no significant differences in the apoptosis rates on MG-63 and KB cells between the antibacterial stainless steel and the control steel. This study demonstrates that the antibacterial stainless steel is possible to reduce the incidence of implant-related infections and can be a more suitable material for the micro-implant than the conventional stainless steel in orthodontic treatment.

  9. Influence of carbon steel grade on the initial attachment of bacteria and microbiologically influenced corrosion.

    PubMed

    Javed, M A; Neil, W C; Stoddart, P R; Wade, S A

    2016-01-01

    The influence of the composition and microstructure of different carbon steel grades on the initial attachment (≤ 60 min) of Escherichia coli and subsequent longer term (28 days) corrosion was investigated. The initial bacterial attachment increased with time on all grades of carbon steel. However, the rate and magnitude of bacterial attachment varied on the different steel grades and was significantly less on the steels with a higher pearlite phase content. The observed variations in the number of bacterial cells attached across different steel grades were significantly reduced by applying a fixed potential to the steel samples. Longer term immersion studies showed similar levels of biofilm formation on the surface of the different grades of carbon steel. The measured corrosion rates were significantly higher in biotic conditions compared to abiotic conditions and were found to be positively correlated with the pearlite phase content of the different grades of carbon steel coupons. PMID:26785935

  10. Laser beam welding of new ultra-high strength and supra-ductile steels

    NASA Astrophysics Data System (ADS)

    Dahmen, Martin

    2015-03-01

    Ultra-high strength and supra-ductile are entering fields of new applications. Those materials are excellent candidates for modern light-weight construction and functional integration. As ultra-high strength steels the stainless martensitic grade 1.4034 and the bainitic steel UNS 53835 are investigated. For the supra-ductile steels stand two high austenitic steels with 18 and 28 % manganese. As there are no processing windows an approach from the metallurgical base on is required. Adjusting the weld microstructure the Q+P and the QT steels require weld heat treatment. The HSD steel is weldable without. Due to their applications the ultra-high strength steels are welded in as-rolled and strengthened condition. Also the reaction of the weld on hot stamping is reflected for the martensitic grades. The supra-ductile steels are welded as solution annealed and work hardened by 50%. The results show the general suitability for laser beam welding.

  11. Progress in bearing performance of advanced nitrogen alloyed stainless steel, Cronidur 30

    SciTech Connect

    Trojahn, W.; Streit, E.; Chin, H.A.; Ehlert, D.

    1998-12-31

    The bearing rig tests performed in this study demonstrate superior bearing performance of Cronidur 30 steel over conventional bearing steels. In these tests the L{sub 10} life of Cronidur 30 steel as calculated by the DIN/ISO 281 method was 80 times the unfactored L{sub 10} life under full lubrication conditions. In boundary lubrication conditions, the Cronidur 30 steel demonstrated the L{sub 10} life capability typical of EHD lubrication conditions, whereas the other steels showed drastically reduced lives. In tests with predamaged races and boundary lubrication conditions, Cronidur 30 demonstrated 8 times the calculated L{sub 10} life, whereas the conventional steels exhibited further reduction in lives. The improved performance of Cronidur 30 steel over conventional bearing steels is attributed to its unique compositional formulation and microstructure that results in provision of balanced properties in the alloy--hardness, toughness, and corrosion resistance.

  12. Influence of carbon steel grade on the initial attachment of bacteria and microbiologically influenced corrosion.

    PubMed

    Javed, M A; Neil, W C; Stoddart, P R; Wade, S A

    2016-01-01

    The influence of the composition and microstructure of different carbon steel grades on the initial attachment (≤ 60 min) of Escherichia coli and subsequent longer term (28 days) corrosion was investigated. The initial bacterial attachment increased with time on all grades of carbon steel. However, the rate and magnitude of bacterial attachment varied on the different steel grades and was significantly less on the steels with a higher pearlite phase content. The observed variations in the number of bacterial cells attached across different steel grades were significantly reduced by applying a fixed potential to the steel samples. Longer term immersion studies showed similar levels of biofilm formation on the surface of the different grades of carbon steel. The measured corrosion rates were significantly higher in biotic conditions compared to abiotic conditions and were found to be positively correlated with the pearlite phase content of the different grades of carbon steel coupons.

  13. Superclean steel development

    SciTech Connect

    Richman, R.H.; McNaughton, W.P. )

    1989-12-01

    The Electric Power Research Institute has actively encouraged and sponsored a number of research projects to develop a superclean 3.5NiCrMoV steel for low pressure turbine rotors. Such steel is highly resistant to temper embrittlement and will thus facilitate increased efficiency in electricity generation through the use of higher operating temperatures and improvements in design. The objective of this interim report was to integrate the results that have been generated to date worldwide in the pursuit of superclean steel. The report contains detailed findings that enable the interested utility to evaluate how the results affect utility decision making. A companion document has been written to summarize the findings from this technical report. The results indicate that steels with impurity contents typical of the superclean specification can be manufactured for production rotors with properties that equal or exceed those for conventional 3.5NiCrMoV rotors in every detail. Of particular interest are the results that the superclean steels appear to be virtually resistant to temper embrittlement to a temperature of 500 {degrees}C. 109 refs., 51 figs., 9 tabs.

  14. 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.

  15. 120. View inside power house showing 1929 AllisChalmers steam turbine ...

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

    120. View inside power house showing 1929 Allis-Chalmers steam turbine with engine housing removed; control panel in background. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  16. Integrity assessment of the ferritic / austenitic dissimilar weld joint between intermediate heat exchanger and steam generator in fast reactor

    SciTech Connect

    Jayakumar, T.; Laha, K.; Chandravathi, K. S.; Parameswaran, P.; Goyal, S.; Kumar, J. G.; Mathew, M. D.

    2012-07-01

    Integrity of the modified 9Cr-1Mo / alloy 800 dissimilar joint welded with Inconel 182 electrodes has been assessed under creep condition based on the detailed analysis of microstructure and stress distribution across the joint by finite element analysis. A hardness peak at the ferritic / austenitic weld interface and a hardness trough at the inter-critical heat affected zone (HAZ) in ferritic base metal developed. Un-tempered martensite was found at the ferritic / austenitic weld interface to impart high hardness in it; whereas annealing of martensitic structure of modified 9Cr-1Mo steel by inter-critical heating during welding thermal cycle resulted in hardness tough in the inter-critical HAZ. Creep tests were carried out on the joint and ferritic steel base metal at 823 K over a stress range of 160-320 MPa. The joint possessed lower creep rupture strength than its ferritic steel base metal. Failure of the joint at relatively lower stresses occurred at the ferritic / austenitic weld interface; whereas it occurred at inter-critical region of HAZ at moderate stresses. Cavity nucleation associated with the weld interface particles led to premature failure of the joint. Finite element analysis of stress distribution across the weld joint considering the micro-mechanical strength inhomogeneity across it revealed higher von-Mises and principal stresses at the weld interface. These stresses induced preferential creep cavitation at the weld interface. Role of precipitate in enhancing creep cavitation at the weld interface has been elucidated based on the FE analysis of stress distribution across it. (authors)

  17. 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.

  18. Continuous steel production and apparatus

    DOEpatents

    Peaslee, Kent D.; Peter, Jorg J.; Robertson, David G. C.; Thomas, Brian G.; Zhang, Lifeng

    2009-11-17

    A process for continuous refining of steel via multiple distinct reaction vessels for melting, oxidation, reduction, and refining for delivery of steel continuously to, for example, a tundish of a continuous caster system, and associated apparatus.

  19. The Role of Steel in the US Economy: Decomposing the 1982-1997 Forward and Backward Linkages of the Steel Industry

    SciTech Connect

    Anderson, Dave M.; Roop, Joseph M.

    2003-08-01

    This paper queries the benchmark input-output tables of the United States for 1982, 1987, 1992, and 1997 to examine both the industries that provide goods and services to the steel industry and the destination of steel products to other industries and final goods. This study provides a sense of how the industry changed from 1982 to 1997 and will aid in evaluation of new technology adoption by linking steel products to final consumers. The steel industry is one of the major producers of raw materials for industry and construction. Value of shipments in 2000 for the steel industry amounted to more than $70 billion. This paper highlights the interdependency of the various steel-using industries of the economy. It shows the downstream use by industry of steel as a commodity. It shows the response in the use of steel to industry-specific shocks to national final demand. It also documents the steel intensity of other industry sectors in the economy. The paper builds on the benchmark input-output tables to develop economic impact models. The effects both of industry final demand on steel and steel's final demand on industry are presented. The paper provides historical context to the observations and trends reflected in the examination of the data.

  20. 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%.

  1. Balance Fatigue Design of Cast Steel Nodes in Tubular Steel Structures

    PubMed Central

    Wang, Libin; Jin, Hui; Li, Jing

    2013-01-01

    Cast steel nodes are being increasingly popular in steel structure joint application as their advanced mechanical performances and flexible forms. This kind of joints improves the structural antifatigue capability observably and is expected to be widely used in the structures with fatigue loadings. Cast steel node joint consists of two parts: casting itself and the welds between the node and the steel member. The fatigue resistances of these two parts are very different; the experiment results showed very clearly that the fatigue behavior was governed by the welds in all tested configurations. This paper focuses on the balance fatigue design of these two parts in a cast steel node joint using fracture mechanics and FEM. The defects in castings are simulated by cracks conservatively. The final crack size is decided by the minimum of 90% of the wall thickness and the value deduced by fracture toughness. The allowable initial crack size could be obtained through the integral of Paris equation when the crack propagation life is considered equal to the weld fatigue life; therefore, the two parts in a cast steel node joint will have a balance fatigue life. PMID:24163621

  2. Electrochemical Corrosion Behavior of Thermal-Sprayed Stainless Steel-Coated Q235 Steel in Simulated Soil Solutions

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Wu, Xin-qiang; Ke, Wei; Xu, Song; Feng, Bing; Hu, Bo-tao

    2016-02-01

    The corrosion behavior of a thermal-sprayed stainless steel (SS)-coated Q235 steel has been investigated in simulated soil solutions using electrochemical measurements, x-ray photoelectron spectroscopy analysis, and scanning electron microscope. The as-received Q235 steel and galvanized steel for grounding grids were also examined for the purpose of comparison. The effects of pH value of testing solutions have been examined. The thermal-sprayed SS-coated steel showed the best corrosion resistance among the three kinds of materials. With increasing pH value, the corrosion resistance of SS-coated Q235 steel increased. In weak alkaline solutions, the SS-coated Q235 steel showed the largest polarization resistance (3.2 × 105 Ω cm2), the lowest anodic current density (1.4 × 10-2 μA/cm2), and the largest film resistance (4.5 × 106 Ω cm2), suggesting that the coated steel has the best corrosion resistance in weak alkaline environment. Related corrosion mechanisms are also discussed.

  3. A-3 steel work completed

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Stennis Space Center engineers celebrated a key milestone in construction of the A-3 Test Stand on April 9 - completion of structural steel work. Workers with Lafayette (La.) Steel Erector Inc. placed the last structural steel beam atop the stand during a noon ceremony attended by more than 100 workers and guests.

  4. Closeup view showing portion of continuous bottom chord of truss ...

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

    Close-up view showing portion of continuous bottom chord of truss with other web members and posts of the truss connected thereto at a joint by the use of a large steel pin. Note: The timber ties supporting the track (not shown but above) span transversely from truss to truss which are on 16' -0 centers. - Bridgeport Swing Span Bridge, Spanning Tennessee River, Bridgeport, Jackson County, AL

  5. 2. EXTERIOR OF FRONT (EAST SIDE) OF BUILDING 105 SHOWING ...

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

    2. EXTERIOR OF FRONT (EAST SIDE) OF BUILDING 105 SHOWING RECESSED PORCH FRAMED BY CRISS-CROSS WOOD BALUSTRADE, STONE FACING ALONG ORIGINAL PORTION OF HOUSE FRONT, AND ORIGINAL PLANK DOOR TO PORCH BASEMENT AT LOWER PHOTO CENTER. WELDED STEEL PORCH RAILINGS VISIBLE AT PHOTO LEFT CENTER WERE ADDED IN 1972. VIEW TO NORTHWEST. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  6. 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.

  7. Strain Hardening Behavior of Dual-Phase Steels

    NASA Astrophysics Data System (ADS)

    Colla, V.; de Sanctis, M.; Dimatteo, A.; Lovicu, G.; Solina, A.; Valentini, R.

    2009-11-01

    A detailed qualitative and quantitative examination of the microstructure and mechanical properties of three different classes of DP600 and DP450 dual-phase (DP) steels was carried out. The tested DP steels are characterized by different alloying elements: aluminum, boron, and phosphorus. Among them, aluminum DP steels showed the lowest percentages of hard phases, while phosphorus DP steels exhibited the highest resistance values. The Hollomon, Pickering, Crussard-Jaoul (CJ), and Bergstrom models were used to reproduce the strain hardening behavior of DP steels. Relationships that correlate the fitting parameters with the chemical composition and the thermal cycle parameters were found, and the predictive abilities of different models were evaluated. The Pickering equation, among the tested models, is the best one in the reproduction of the experimental stress-strain data.

  8. Mechanical behavior study of laser welded joints for DP steel

    NASA Astrophysics Data System (ADS)

    Yan, Qi

    2008-03-01

    Advanced High Strength Steels (AHSS) are gaining considerable market shares in the automotive industry. The development and application of Dual Phase (DP) steel is just a consistent step towards high-strength steel grades with improved mechanical behavior. Tailor welded blanks with DP steel are promoted in the application of Body-In-White (BIW) structure by the automotive industry. A tailor welded blank consists of several flat sheets that are laser welded together before stamping. Applied cases of tailor welded blanks of high strength steels on the automotive structural parts are investigated in this paper. The mechanical behavior of laser welded joints for DP steel is studied. Microstructure of laser welded joints for DP steel was observed by SEM. Martensite in the weld seam explains the higher strength of welded joints than the base metal. Results show that the strain safety tolerance of laser welded seam for high strength steel can meet the requirement of automobile parts for stamping if the location of laser welded seam is designed reasonably.

  9. 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.

  10. 8. Detail showing concrete abutment, showing substructure of bridge, specifically ...

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

    8. Detail showing concrete abutment, showing substructure of bridge, specifically west side of arch and substructure. - Presumpscot Falls Bridge, Spanning Presumptscot River at Allen Avenue extension, 0.75 mile west of U.S. Interstate 95, Falmouth, Cumberland County, ME

  11. 28. MAP SHOWING LOCATION OF ARVFS FACILITY AS BUILT. SHOWS ...

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

    28. MAP SHOWING LOCATION OF ARVFS FACILITY AS BUILT. SHOWS LINCOLN BOULEVARD, BIG LOST RIVER, AND NAVAL REACTORS FACILITY. F.C. TORKELSON DRAWING NUMBER 842-ARVFS-101-2. DATED OCTOBER 12, 1965. INEL INDEX CODE NUMBER: 075 0101 851 151969. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  12. 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.

  13. Braze alloy spreading on steel

    NASA Technical Reports Server (NTRS)

    Siewert, T. A.; Heine, R. W.; Lagally, M. G.

    1978-01-01

    Scanning electron microscopy (SEM) and Auger electron microscopy (AEM) were employed to observe elemental surface decomposition resulting from the brazing of a copper-treated steel. Two types of steel were used for the study, stainless steel (treated with a eutectic silver-copper alloy), and low-carbon steel (treated with pure copper). Attention is given to oxygen partial pressure during the processes; a low enough pressure (8 x 10 to the -5th torr) was found to totally inhibit the spreading of the filler material at a fixed heating cycle. With both types of steel, copper treatment enhanced even spreading at a decreased temperature.

  14. Evaluation of Steel Cleanliness in a Steel Deoxidized Using Al

    NASA Astrophysics Data System (ADS)

    Castro-Cedeño, Edgar-Ivan; Herrera-Trejo, Martín; Castro-Román, Manuel; Castro-Uresti, Fabián; López-Cornejo, Monserrat

    2016-06-01

    The effect of magnesium in the aluminum used as a deoxidizer on the cleanliness of steel was studied throughout a steelmaking route for the production of thin slabs. Two deoxidizers with different Mg contents were used. The Mg content of a "typical" deoxidizer was ~0.5 wt pct Mg, whereas that for an alternative deoxidizer was ~2 wt pct Mg. The inclusion population at different stages of the steelmaking process was characterized in terms of chemical composition, number, and size distribution. The inclusion modification path shows that the solid Al2O3 and Al2O3-MgO inclusions formed in the early stage of the steel ladle treatment are modified into Al2O3-MgO-CaO liquid and MgO-Al2O3-liquid inclusions. Although some slight differences were observed in the ladle furnace samples, the chemical composition of inclusions was similar in the samples taken at the mold of the continuous casting, regardless of the deoxidizer used. Gumbel, generalized extreme value (GEV), and generalized Pareto (GP) distributions were used for the description of the size distribution. The GEV and GP distributions resulted in proper distributions to describe the evolution of size distribution throughout the steelmaking process. Furthermore, no statistically significant differences between inclusion size distributions resulting from the use of either deoxidizer were found.

  15. Comparative Analysis of Uniaxial Strain Shock Tests and Taylor Tests for Armor and Maraging Steels

    NASA Astrophysics Data System (ADS)

    Mescheryakov, Yu. I.; Zhigacheva, N. I.; Petrov, Yu. A.; Divakov, A. K.; Cline, C. F.

    2004-07-01

    High-strength constructional 38KhN3MFA steel and 02H18К9M5-BИ maraging steel were tested to determine the yield stress under dynamic loading. The 38KhN3MFA steel was used as central test material to work out the experimental technique. For both kinds of steel the results obtained in the plane shock tests under uniaxial strain condition show approximately the identical yield stress values as those obtained in Taylor tests. Cracking of maraging steel occurs along the shock-induced austenite bands where microhardness is much smaller than that for the rest of the matrix.

  16. 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

  17. 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.

  18. 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).

  19. Special steel production on common carbon steel production line

    NASA Astrophysics Data System (ADS)

    Pi, Huachun; Han, Jingtao; Hu, Haiping; Bian, Ruisheng; Kang, Jianjun; Xu, Manlin

    2004-06-01

    The equipment and technology of small bar tandem rolling line of Shijiazhuang Iron & Steel Co. in China has reached the 90's international advanced level in the 20th century, but products on the line are mostly of common carbon steel. Currently there are few steel plants in China to produce 45 steel bars for cold drawing, which is a kind of shortage product. Development of 45 steel for cold drawing has a wide market outlook in China. In this paper, continuous cooling transformation (CCT) curve of 45 steel for cold drawing used for rolling was set out first. According to the CCT curve, we determined some key temperature points such as Ac3 temperature and Ac1 temperature during the cooling procedure and discussed the precipitation microstructure at different cooling rate. Then by studying thermal treatment process of 45 steel bars for cold drawing, the influence of cooling time on microstructure was analyzed and the optimum cooling speed has been found. All results concluded from the above studies are the basis of regulating controlled cooling process of 45 steel bars for cold drawing. Finally, the feasible production process of 45 steel bars for cold drawing on common carbon steel production line combined with the field condition was recommended.

  20. What Do Blood Tests Show?

    MedlinePlus

    ... shows the ranges for blood glucose levels after 8 to 12 hours of fasting (not eating). It shows the normal range and the abnormal ranges that are a sign of prediabetes or diabetes. Plasma Glucose Results (mg/dL)* Diagnosis 70 to 99 ...

  1. Recycling steel from grinding swarf

    SciTech Connect

    Fu, H.; Matthews, M.A.; Warner, L.S.

    1998-12-31

    Two cleaning processes have been investigated for removing contaminants (cutting oil with phosphorus ester) from high speed steel (HSS) griding swarf. One process uses an aqueous surfactant washing technique, and the second process uses supercritical carbon dioxide (SCCO{sub 2}) extraction. Both technical and preliminary financial analysis are performed to have a better evaluation of these two competing cleaning technologies. Bench scale aqueous washings have shown that the required phosphorus removal is easily obtained, but a sufficient oil removal is more difficult. The experimental results also indicate a strong dependence of the aqueous washing efficiency on the choice of a suitable surfactant. SCCO{sub 2} extraction at 80 C and 340 atm shows that approximately 80% of the oil can be removed from swarf during a 60-minute process to produce a batch of recyclable steel, and that the phosphorus removal also reaches the required level. The cost of processing swarf using either aqueous surfactant washing or SCCO{sub 2} extraction in a 3,000,000 lbs per year plant is analyzed and the market forces impacting the feasibility of recycling on a commercial basis are reviewed. Commercial scale recycling is, in part, dependent upon resolution of regulatory uncertainty on the definition of swarf. States regulating swarf as hazardous provide a significant financial incentive to recycle. In states that regulate swarf as a solid waste, low disposal costs provide a disincentive that must be balanced with the possible hidden, future liabilities of landfill disposal.

  2. Ferritic steel melt and FLiBe/steel experiment : melting ferritic steel.

    SciTech Connect

    Troncosa, Kenneth P.; Smith, Brandon M.; Tanaka, Tina Joan

    2004-11-01

    In preparation for developing a Z-pinch IFE power plant, the interaction of ferritic steel with the coolant, FLiBe, must be explored. Sandia National Laboratories Fusion Technology Department was asked to drop molten ferritic steel and FLiBe in a vacuum system and determine the gas byproducts and ability to recycle the steel. We tried various methods of resistive heating of ferritic steel using available power supplies and easily obtained heaters. Although we could melt the steel, we could not cause a drop to fall. This report describes the various experiments that were performed and includes some suggestions and materials needed to be successful. Although the steel was easily melted, it was not possible to drip the molten steel into a FLiBe pool Levitation melting of the drop is likely to be more successful.

  3. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  4. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  5. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  6. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  7. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  8. Description of full-range strain hardening behavior of steels.

    PubMed

    Li, Tao; Zheng, Jinyang; Chen, Zhiwei

    2016-01-01

    Mathematical expression describing plastic behavior of steels allows the execution of parametric studies for many purposes. Various formulas have been developed to characterize stress strain curves of steels. However, most of those formulas failed to describe accurately the strain hardening behavior of steels in the full range which shows various distinct stages. For this purpose, a new formula is developed based on the well-known Ramberg-Osgood formula to describe the full range strain hardening behavior of steels. Test results of all the six types of steels show a three-stage strain hardening behavior. The proposed formula can describe such behavior accurately in the full range using a single expression. The parameters of the formula can be obtained directly and easily through linear regression analysis. Excellent agreements with the test data are observed for all the steels tested. Furthermore, other formulas such as Ludwigson formula, Gardner formula, UGent formula are also applied for comparison. Finally, the proposed formula is considered to have wide suitability and high accuracy for all the steels tested.

  9. Description of full-range strain hardening behavior of steels.

    PubMed

    Li, Tao; Zheng, Jinyang; Chen, Zhiwei

    2016-01-01

    Mathematical expression describing plastic behavior of steels allows the execution of parametric studies for many purposes. Various formulas have been developed to characterize stress strain curves of steels. However, most of those formulas failed to describe accurately the strain hardening behavior of steels in the full range which shows various distinct stages. For this purpose, a new formula is developed based on the well-known Ramberg-Osgood formula to describe the full range strain hardening behavior of steels. Test results of all the six types of steels show a three-stage strain hardening behavior. The proposed formula can describe such behavior accurately in the full range using a single expression. The parameters of the formula can be obtained directly and easily through linear regression analysis. Excellent agreements with the test data are observed for all the steels tested. Furthermore, other formulas such as Ludwigson formula, Gardner formula, UGent formula are also applied for comparison. Finally, the proposed formula is considered to have wide suitability and high accuracy for all the steels tested. PMID:27563511

  10. Satellite Movie Shows Erika Dissipate

    NASA Video Gallery

    This animation of visible and infrared imagery from NOAA's GOES-West satellite from Aug. 27 to 29 shows Tropical Storm Erika move through the Eastern Caribbean Sea and dissipate near eastern Cuba. ...

  11. History of ultrahigh carbon steels

    SciTech Connect

    Wadsworth, J.; Sherby, O.D.

    1997-06-20

    The history and development of ultrahigh carbon steels (i.e., steels containing between 1 and 2.l percent C and now known as UHCS) are described. The early use of steel compositions containing carbon contents above the eutectoid level is found in ancient weapons from around the world. For example, both Damascus and Japanese sword steels are hypereutectoid steels. Their manufacture and processing is of interest in understanding the role of carbon content in the development of modern steels. Although sporadic examples of UHCS compositions are found in steels examined in the early part of this century, it was not until the mid-1970s that the modern study began. This study had its origin in the development of superplastic behavior in steels and the recognition that increasing the carbon content was of importance in developing that property. The compositions that were optimal for superplasticity involved the development of steels that contained higher carbon contents than conventional modern steels. It was discovered, however, that the room temperature properties of these compositions were of interest in their own right. Following this discovery, a period of intense work began on understanding their manufacture, processing, and properties for both superplastic forming and room temperature applications. The development of superplastic cast irons and iron carbides, as well as those of laminated composites containing UHCS, was an important part of this history.

  12. Respiratory status of stainless steel and mild steel welders.

    PubMed

    Kalliomäki, P L; Kalliomäki, K; Korhonen, O; Nordman, H; Rahkonen, E; Vaaranen, V

    1982-01-01

    Eighty-three full-time stainless steel and 29 mild steel welders from one shipyard were examined clinically, and their lung function was measured. The stainless steel welders had used both tungsten inert-gas (low-fume concentration) and manual metal-arc (MMA) (high-fume concentration) welding methods. The individual exposure of the welders was estimated based on the time spent doing MMA welding, the amount of retained contaminants in the lungs (magnetopulmography), and urinary chromium excretion. The results suggest that there is a greater prevalence of small airway disease among shipyard mild steel MMA welders than among stainless steel welders. Among the stainless steel welders the impairment of lung function parameters was associated with the MMA welding method. The type of welding, then, is important when the health hazards of welders are studied, and welders cannot be regarded as a single, homogeneous group. PMID:7100838

  13. Microstructure-Fracture Behavior Relationships of Slot-Welded Rail Steels

    NASA Astrophysics Data System (ADS)

    Allie, Aldinton; Aglan, Heshmat; Fateh, Mahmood

    2011-09-01

    Microstructural analyses of the parent pearlitic and bainitic rail steels were performed, and the results were compared with the microstructure of the welded pearlitic and bainitic steels. An increase in the ASTM grain size number of the heat-affected zone (HAZ) for both pearlitic and bainitic slot welds was observed. The microstructural features that were identified in the weldment of both slot-welded steels were very similar. This was expected since the same welding wire was used to weld both rail steels. The weld consisted of mainly ferrite and had similar grain size. The fusion zones of the welded pearlitic and bainitic rail steels were examined after flexural tests to determine if there were any cracks present due to improper or weak fusion. Examination of the entire fusion zone under high optical magnification revealed no cracks, indicating that a perfect fusion was achieved. The three-point flexural behavior of the parent pearlitic and bainitic steels was evaluated and compared with that of the slot-welded steels. It was found that that the welded pearlitic steel has superior fracture resistance properties when compared to the parent pearlitic steel. The average fracture resistance of the parent pearlitic steel was 79 MPa√m compared to 119 MPa√m for the welded pearlitic steel. The slot-welded bainitic steel, however, showed similar fracture resistance properties to the parent bainitic steel with average values of 121 and 128 MPa√m, respectively. The failure mechanism of the welded and parent pearlitic and bainitic steels was also identified. Microvoid coalescence was observed in both welded rail steel samples. This was manifested by dimpled features, which are associated with ductile failure.

  14. Induced minisatellite germline mutations in herring gulls (Larus argentatus) living near steel mills.

    PubMed

    Yauk, C L; Fox, G A; McCarry, B E; Quinn, J S

    2000-09-18

    Despite widespread industrial release of genotoxic contaminants, little is understood of their role in inducing germline mutations in natural populations. We used multilocus DNA fingerprinting to quantify germline minisatellite mutations in families of herring gulls (Larus argentatus) in three nesting categories: (a) near cities with large steel mills operating coking ovens; (b) near cities without steel mills; and (c) in rural locations removed from point sources of contamination. Gulls nesting near integrated steel mills showed significantly higher mutation rates than gulls from rural locations (Fisher's exact, P=0.0004); urban sites without steel mills fell midway between steel and rural sites (difference from rural; Fisher's exact, P=0.19). Distance of the nesting location of herring gulls from the steel industries' coking ovens was negatively correlated with minisatellite mutation rate demonstrating significant risk for induced germline mutations in cities with steel operations (Kendall Tau; tau=0.119; P<0.0001). PMID:11024480

  15. National Orange Show Photovoltaic Demonstration

    SciTech Connect

    Dan Jimenez Sheri Raborn, CPA; Tom Baker

    2008-03-31

    National Orange Show Photovoltaic Demonstration created a 400KW Photovoltaic self-generation plant at the National Orange Show Events Center (NOS). The NOS owns a 120-acre state fairground where it operates an events center and produces an annual citrus fair known as the Orange Show. The NOS governing board wanted to employ cost-saving programs for annual energy expenses. It is hoped the Photovoltaic program will result in overall savings for the NOS, help reduce the State's energy demands as relating to electrical power consumption, improve quality of life within the affected grid area as well as increase the energy efficiency of buildings at our venue. In addition, the potential to reduce operational expenses would have a tremendous effect on the ability of the NOS to service its community.

  16. Arches showing UV flaring activity

    NASA Technical Reports Server (NTRS)

    Fontenla, J. M.

    1988-01-01

    The UVSP data obtained in the previous maximum activity cycle show the frequent appearance of flaring events in the UV. In many cases these flaring events are characterized by at least two footpoints which show compact impulsive non-simultaneous brightenings and a fainter but clearly observed arch developes between the footpoints. These arches and footpoints are observed in line corresponding to different temperatures, as Lyman alpha, N V, and C IV, and when observed above the limb display large Doppler shifts at some stages. The size of the arches can be larger than 20 arcsec.

  17. Create a Polarized Light Show.

    ERIC Educational Resources Information Center

    Conrad, William H.

    1992-01-01

    Presents a lesson that introduces students to polarized light using a problem-solving approach. After illustrating the concept using a slinky and poster board with a vertical slot, students solve the problem of creating a polarized light show using Polya's problem-solving methods. (MDH)

  18. Pembrolizumab Shows Promise for NSCLC.

    PubMed

    2015-06-01

    Data from the KEYNOTE-001 trial show that pembrolizumab improves clinical outcomes for patients with advanced non-small cell lung cancer, and is well tolerated. PD-L1 expression in at least 50% of tumor cells correlated with improved efficacy.

  19. Springback analysis of ultra high strength steel

    NASA Astrophysics Data System (ADS)

    Tenma, Kenji; Kina, Futoshi; Suzuki, Wataru

    2013-12-01

    It is an inevitable trend in the automotive industry to apply more and more high strength steels and even ultra-high strength steels. Even though these materials are more difficult to process the development time of forming tools must be reduced. In order to keep the development time under control, simulation tools are used to verify the forming process in advance. At Aoi Machine Industry a project has been executed to accurately simulate springback of ultra-high strength steels in order to reduce the tool tryout time. In the first phase of the project the simulation settings were optimized based on B-Pillar model A made of Dual Phase 980. In the second phase, it was verified with B-Pillar model B whether these simulation settings were usable as general setting. Results showed that with the right settings it is very well possible to accurately simulate springback of ultra-high strength steels. In the third phase the project the stamping of a B-Pillar of Dual Phase 1180 was studied.

  20. 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.

  1. Effect of Sputtered AlY Coating on High-Temperature Oxidation Behavior of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Fu, Guangyan; Xie, Huanzhang; Su, Yong; Qi, Zeyan; Hou, Qiang

    2016-08-01

    AlY coating on 1Cr18Ni9Ti stainless steel was prepared by magnetron sputtering method and some of them were pre-oxidized or vacuum diffusion annealed at 600°C, and the effect of the coating with different treatments on the oxidation behavior of the stainless steel was studied at 1,100°C in air. Results show that the order of the 24-h oxidation mass gain for the specimens is the stainless steel without coating > the stainless steel with coating but without any pre-treatment > the stainless steel with AlY coating after pre-oxidation treatment > the stainless steel with AlY coating after vacuum diffusion annealing. After oxidation, a thick and loose Fe2O3/Cr2O3 film is formed on the stainless steel without coating, while thinner Fe2O3/Cr2O3 film is formed on the stainless steel with AlY coating. Compared to the oxidation film formed on the steel with pre-oxidized coating, the one formed on the steel with vacuum diffusion annealed coating is thinner and denser. The rare earth Y and its oxides Y2O3 in the coating produce reactive element effect and improve the ductility/adhesion of the oxide film, which enhances the oxidation resistance of the stainless steel, especially in the vacuum diffusion annealed AlY coating.

  2. Passivation and Corrosion Behavior of Modified Ferritic-Pearlitic Railway Axle Steels

    NASA Astrophysics Data System (ADS)

    Moon, A. P.; Sangal, S.; Srivastav, Simant; Gajbhiye, N. S.; Mondal, K.

    2015-01-01

    Electrochemical polarization behavior of two newly developed ferritic-pearlitic railway axle steels (MS3 and MS6) and the standard Indian conventional axle steel has been studied in sodium borate buffer solution of pH 8.4 with and without the presence of NaCl. The polarization behavior of both the new axle steels shows close resemblance, whereas, different polarization behavior has been observed for the conventional axle steel. Electrochemical impedance spectroscopy measurements have clearly reflected significantly improved passivation behavior for the newly developed steels compared to that of the conventional axle steel. NaCl salt fog exposure tests have also shown superior corrosion resistance of the newly developed axle steels as compared to the conventional axle steel. Higher surface roughness on the corroded conventional axle steel has also been observed compared to the smoother surface in case of the new axle steels. Higher corrosion resistance of the new axle steels has been attributed to their finer microstructure and strongly adherent protective rusts.

  3. Study of Influence of Heat Treatment on Cyclic Properties of L21HMF Cast Steel

    NASA Astrophysics Data System (ADS)

    Mroziński, Stanisław; Golański, Grzegorz

    2016-07-01

    This work presents the results of studies of CrMoV cast steel after long-term service and after regenerative heat treatment (RHT). The cast steel was investigated in the conditions of static and changeable load. The tests were carried out at room temperature and 550 °C. The fatigue lifetime curves were determined and described using the Basquin-Manson-Coffin relationship. It has been shown that the cast steel after RHT is characterized by smaller range of plastic strain and bigger range of stress amplitude, with the same value of total strain, compared with the cast steel after service. For the cast steel after RHT, the observed fatigue properties were different in comparison with the cast steel after service at small and large strains. At room temperature (20 °C) and at elevated temperature (550 °C), there is an increase in the life of samples of the cast steel after RHT in comparison with the samples of the cast steel after service only in the area of large strains ( ɛ ac > 1.2%). For small strains ɛ ac < 0.50%, the life of the cast steel after RHT at the examined temperatures is shorter than that of the cast steel after service. The paper shows that regardless of an explicit improvement in the strength properties (the static and cyclic ones), as a result of the performed RHT, a complete improvement in the fatigue properties of the cast steel does not occur.

  4. TMD-Based Structural Control of High Performance Steel Bridges

    NASA Astrophysics Data System (ADS)

    Kim, Tae Min; Kim, Gun; Kyum Kim, Moon

    2012-08-01

    The purpose of this study is to investigate the effectiveness of structural control using tuned mass damper (TMD) for suppressing excessive traffic induced vibration of high performance steel bridge. The study considered 1-span steel plate girder bridge and bridge-vehicle interaction using HS-24 truck model. A numerical model of steel plate girder, traffic load, and TMD is constructed and time history analysis is performed using commercial structural analysis program ABAQUS 6.10. Results from analyses show that high performance steel bridge has dynamic serviceability problem, compared to relatively low performance steel bridge. Therefore, the structural control using TMD is implemented in order to alleviate dynamic serviceability problems. TMD is applied to the bridge with high performance steel and then vertical vibration due to dynamic behavior is assessed again. In consequent, by using TMD, it is confirmed that the residual amplitude is appreciably reduced by 85% in steady-state vibration. Moreover, vibration serviceability assessment using 'Reiher-Meister Curve' is also remarkably improved. As a result, this paper provides the guideline for economical design of I-girder using high performance steel and evaluates the effectiveness of structural control using TMD, simultaneously.

  5. Surface microanalytical studies of nitrogen ion-implanted steel

    NASA Astrophysics Data System (ADS)

    Dodd, Charles G.; Meeker, G. P.; Baumann, Scott M.; Norberg, James C.; Legg, Keith O.

    1985-03-01

    Five types of industrial steels, 1018, 52100, M-2, 440C, and 304 were ion implanted with nitrogen and subjected to surface microanalysis by three independent surface techniques: AES, RBS, and SIMS. The results provided understanding for earlier observations of the properties of various types of steel after nitrogen implantation. The steels that retained the most nitrogen and that have been reported to benefit the most in improved tribological properties from ion implantation were ferritic carbon and austenitic stainless steels, such as soft 1018 and 304, respectively. Heat-treated martensitic carbon steels such as 52100 and M-2 tool steel were found to retain the least nitrogen, and they have been reported to benefit less from nitrogen implantation; however, the interaction of transition metal carbides in M-2 with nitrogen has not been clarified. The data showed that 440C steel retained as much nitrogen as 1018 and 304, but treatment benefits may be limited to improvements in properties related to toughness and impact resistance.

  6. Steel Reoxidation by Gunning Mass and Tundish Slag

    NASA Astrophysics Data System (ADS)

    Yan, Pengcheng; Arnout, Sander; Van Ende, Marie-Aline; Zinngrebe, Enno; Jones, Tom; Blanpain, Bart; Guo, Muxing

    2015-01-01

    Steel reoxidation in the tundish has a significant influence on the steel cleanliness and therefore on the mechanical properties of the final product. In the present work, the steel reoxidation by two types of gunning mass (GM), viz. magnesia- and alumina-based GM, and two types of tundish slag, viz. lime-alumina-silica and lime-alumina slags, has been investigated. The evolution of the steel composition during the test was analyzed and predicted based on thermodynamic and kinetic considerations. The calculated steel composition agrees well with measured values, when assuming the mass transfer in slag phase limits the reoxidation reactions. The oxidation capacity of the gunning mass and tundish slag is quantified by calculating the oxygen amount supplied from the GM and the slag to the steel phase. It was found that compared to alumina GM, magnesia GM exhibits a stronger oxidation capacity due to its higher content of reducible oxides (10 wt pct SiO2 + 6 wt pct FeO). Compared to lime-alumina-silica tundish slag, lime-alumina slag (with more FeO + MnO contents) provides more oxygen to the molten steel in the present experimental conditions and consequently shows a stronger oxidation capacity.

  7. The morphology and formation mechanism of pearlite in steels

    SciTech Connect

    Zhang, M.-X.; Kelly, P.M.

    2009-06-15

    A number of morphological features of pearlite were revealed through scanning electron microscopy using deeply etched specimens. These include cementite branching, bridging, gaps, holes and curvature. The presence of cementite thin films or networks along the austenite grain boundaries in eutectoid steel and at the interface between pearlite and proeutectoid ferrite in hypoeutectoid steel is another characteristic of pearlite. Furthermore, ferrite thin films surrounding the proeutectoid cementite in hypereutectoid steels are also observed. Hence, it is considered that in hypoeutectoid steels the nucleus for pearlite is a film of cementite rather than the expected proeutectoid ferrite and, similarly, in hypereutectoid steels pearlite forms from a ferrite film rather than from proeutectoid cementite. Convergent beam Kikuchi line diffraction was used to accurately determine the orientation relationships between pearlitic constituents and parent austenite in a Hadfields steel. The results show that neither the pearlitic ferrite nor the cementite is crystallographically related to the austenite grain into which the pearlite was growing and to that into which it was not growing. In addition, a new orientation relationship between pearlitic cementite and ferrite in the Hadfield steel was also observed.

  8. Compatibility tests of steels in flowing liquid lead-bismuth

    NASA Astrophysics Data System (ADS)

    Barbier, F.; Benamati, G.; Fazio, C.; Rusanov, A.

    2001-06-01

    The behaviour of steels exposed to flowing Pb-55Bi was evaluated. The materials tested are the two austenitic steels AISI 316L and 1.4970, and the six martensitic steels Optifer IVc, T91, Batman 27, Batman 28, EP823 and EM10 which were exposed to flowing Pb-55Bi for 1000, 2000 and 3000 h and at two temperatures (573 and 743 K). The corrosion tests were conducted in the non-isothermal loop of IPPE-Obninsk under a controlled oxygen level (10 -6 wt%). The compatibility study showed that at a lower temperature, a very thin oxide layer (<1 μm) was formed on the steels. At higher temperature, austenitic steels also exhibited a thin oxide layer sufficient to prevent their dissolution in the melt. A thicker oxide, which grew according to a parabolic law, was observed on the surface of the martensitic steels. The oxidation resistance behaviour of the martensitic steels was correlated with their alloying elements.

  9. Magic Carpet Shows Its Colors

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The upper left image in this display is from the panoramic camera on the Mars Exploration Rover Spirit, showing the 'Magic Carpet' region near the rover at Gusev Crater, Mars, on Sol 7, the seventh martian day of its journey (Jan. 10, 2004). The lower image, also from the panoramic camera, is a monochrome (single filter) image of a rock in the 'Magic Carpet' area. Note that colored portions of the rock correlate with extracted spectra shown in the plot to the side. Four different types of materials are shown: the rock itself, the soil in front of the rock, some brighter soil on top of the rock, and some dust that has collected in small recesses on the rock face ('spots'). Each color on the spectra matches a line on the graph, showing how the panoramic camera's different colored filters are used to broadly assess the varying mineral compositions of martian rocks and soils.

  10. Ultrasonic attenuation in pearlitic steel.

    PubMed

    Du, Hualong; Turner, Joseph A

    2014-03-01

    Expressions for the attenuation coefficients of longitudinal and transverse ultrasonic waves are developed for steel with pearlitic microstructure. This type of lamellar duplex microstructure influences attenuation because of the lamellar spacing. In addition, longitudinal attenuation measurements were conducted using an unfocused transducer with 10 MHz central frequency on the cross section of a quenched railroad wheel sample. The dependence of longitudinal attenuation on the pearlite microstructure is observed from the changes of longitudinal attenuation from the quenched tread surface to deeper locations. The results show that the attenuation value is lowest and relatively constant within the quench depth, then increases linearly. The experimental results demonstrate a reasonable agreement with results from the theoretical model. Ultrasonic attenuation provides an important non-destructive method to evaluate duplex microstructure within grains which can be implemented for quality control in conjunction with other manufacturing processes.

  11. Mechanical performance of thermally post-treated ion-nitrided steels

    NASA Astrophysics Data System (ADS)

    Rosales, I.; Martinez, H.; Guardian, R.

    2016-05-01

    To obtain an enlarged nitrided layer, a new diffusion heat treatment was applied to three different ion-nitriding steels. Selected steels were from the AISI series: 1045, O1, and H13. Fractographic analyses showed that layers of each one of the steels considerably grew after being exposed to diffusion heat treatment. Micro-hardness tests indicated that the modified steels showed a similar value when is compared with the nitrided condition. By comparing the results in fracture toughness tests, it was observed that the most positively affected steel by the treatment was the AISI-1045 steel. Wear analyses showed that diffusion heat-treated samples exhibited an enhanced wear behavior under moderate loads.

  12. 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.

  13. Process for dezincing galvanized steel

    DOEpatents

    Morgan, William A.; Dudek, Frederick J.; Daniels, Edward J.

    1998-01-01

    A process for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75.degree. C. and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series. The corrosion rate may be accelerated by (i) increasing the number density of corrosion sites in the galvanized steel by mechanically abrading or deforming the galvanized steel, (ii) heating the galvanized steel to form an alloy of zinc on the surface of the galvanized steel, (iii) mixing the galvanized steel with a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series, or (iv) moving the galvanized steel relative to itself and to the electrolyte while immersed in the electrolyte.

  14. Process for dezincing galvanized steel

    DOEpatents

    Morgan, W.A.; Dudek, F.J.; Daniels, E.J.

    1998-07-14

    A process is described for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75 C and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series. The corrosion rate may be accelerated by (1) increasing the number density of corrosion sites in the galvanized steel by mechanically abrading or deforming the galvanized steel, (2) heating the galvanized steel to form an alloy of zinc on the surface of the galvanized steel, (3) mixing the galvanized steel with a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series, or (4) moving the galvanized steel relative to itself and to the electrolyte while immersed in the electrolyte. 1 fig.

  15. Induction heat treatment of steel

    SciTech Connect

    Semiatin, S.L.; Stutz, D.E.

    1985-01-01

    This book discusses the induction heating. After reviewing heat treating operations for steel and the principles of the heat treatment of steel, an overview of induction heat treating is provided. Next, consideration is given to equipment and equipment selection, coil design, power requirements and temperature control. A discussion of surface and through hardening of steel is provided, including information on frequency and power selection and quenching apparatus. Tempering is considered, followed by information on control of residual stresses, cracking, temper brittleness and the important metallurgical and hardness differences between induction and furnace treated steel.

  16. High strength, tough alloy steel

    DOEpatents

    Thomas, Gareth; Rao, Bangaru V. N.

    1979-01-01

    A high strength, tough alloy steel is formed by heating the steel to a temperature in the austenite range (1000.degree.-1100.degree. C.) to form a homogeneous austenite phase and then cooling the steel to form a microstructure of uniformly dispersed dislocated martensite separated by continuous thin boundary films of stabilized retained austenite. The steel includes 0.2-0.35 weight % carbon, at least 1% and preferably 3-4.5% chromium, and at least one other substitutional alloying element, preferably manganese or nickel. The austenite film is stable to subsequent heat treatment as by tempering (below 300.degree. C.) and reforms to a stable film after austenite grain refinement.

  17. Weak ferromagnetism in `non-magnetic' austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Crangle, John; Fogarty, A.; Taylor, M. J.

    1992-06-01

    The magnetization and susceptability of the non-magnetic stainless steels AISI 304 and AISI 316 have been measured at low temperatures using a SQUID magnetometer. A small but stable ferromagnetic component is always present. Field cooling shows the effects of exchange anisotropy. Another stainless steel AISI 321 is non-magnetic at room temperature but it transforms irreversibly to a partially ferromagnetic state when it is cooled below 280 K.

  18. Dianils: New and effective corrosion inhibitors for oil-well steel (N-80) and mild steel in boiling hydrochloric acid

    SciTech Connect

    Quraishi, M.A.; Jamal, D.

    2000-02-01

    Selected condensation products of aromatic aldehydes and p-phenylenediamine have been synthesized and evaluated as corrosion inhibitors for mild steel (MS) and oil-well steel (N-80) in 15% hydrochloric acid (HCl) at 105 C {+-} 2 C by the weight loss method. All the condensation products showed excellent performance. 2,4-dicinnamyledene aminophenylene (DCAP) was found to be the best corrosion inhibitor. It exhibited 99.75% inhibition efficiency (IE) for MS and 99.12% for N-80 steel at 5,000 ppm of inhibitor concentration. The potentiodynamic polarization studies carried out at room temperature on MS in 15% HCl containing 500 ppm of condensation products showed that all the investigated compounds were mixed type inhibitors, whereas 500 ppm DCAP on N-80 steel behaved predominantly as anodic inhibitors. The adsorption of all the condensation products was found to obey Temkin's adsorption isotherm.

  19. Clean cast steel technology. Final report

    SciTech Connect

    Bates, C.E.; Griffin, J.A.

    1998-06-01

    This report documents the results obtained from the Clean Cast Steel Technology Program financially supported by the DOE Metal Casting Competitiveness Research Program and industry. The primary objective of this program is to develop technology for delivering steel free of oxide macroinclusions to mold cavities. The overall objective is to improve the quality of cast steel by developing and demonstrating the technology for substantially reducing surface and sub-surface oxide inclusions. Two approaches are discussed here. A total of 23 castings were produced by submerge pouring along with sixty conventionally poured castings. The submerged poured castings contained, on average, 96% fewer observable surface inclusions (11.9 vs 0.4) compared to the conventionally poured cast parts. The variation in the population of surface inclusions also decreased by 88% from 5.5 to 0.7. The machinability of the casting was also improved by submerged pouring. The submerge poured castings required fewer cutting tool changes and less operator intervention during machining. Subsequent to these trials, the foundry has decided to purchase more shrouds for continued experimentation on other problem castings where submerge pouring is possible. An examination of melting and pouring practices in four foundries has been carried out. Three of the four foundries showed significant improvement in casting quality by manipulating the melting practice. These melting practice variables can be grouped into two separate categories. The first category is the pouring and filling practice. The second category concerns the concentration of oxidizable elements contained in the steel. Silicon, manganese, and aluminum concentrations were important factors in all four foundries. Clean heats can consistently be produced through improved melting practice and reducing exposure of the steel to atmospheric oxygen during pouring and filling.

  20. ShowMe3D

    SciTech Connect

    Sinclair, Michael B

    2012-01-05

    ShowMe3D is a data visualization graphical user interface specifically designed for use with hyperspectral image obtained from the Hyperspectral Confocal Microscope. The program allows the user to select and display any single image from a three dimensional hyperspectral image stack. By moving a slider control, the user can easily move between images of the stack. The user can zoom into any region of the image. The user can select any pixel or region from the displayed image and display the fluorescence spectrum associated with that pixel or region. The user can define up to 3 spectral filters to apply to the hyperspectral image and view the image as it would appear from a filter-based confocal microscope. The user can also obtain statistics such as intensity average and variance from selected regions.

  1. "Show me" bioethics and politics.

    PubMed

    Christopher, Myra J

    2007-10-01

    Missouri, the "Show Me State," has become the epicenter of several important national public policy debates, including abortion rights, the right to choose and refuse medical treatment, and, most recently, early stem cell research. In this environment, the Center for Practical Bioethics (formerly, Midwest Bioethics Center) emerged and grew. The Center's role in these "cultural wars" is not to advocate for a particular position but to provide well researched and objective information, perspective, and advocacy for the ethical justification of policy positions; and to serve as a neutral convener and provider of a public forum for discussion. In this article, the Center's work on early stem cell research is a case study through which to argue that not only the Center, but also the field of bioethics has a critical role in the politics of public health policy.

  2. ShowMe3D

    2012-01-05

    ShowMe3D is a data visualization graphical user interface specifically designed for use with hyperspectral image obtained from the Hyperspectral Confocal Microscope. The program allows the user to select and display any single image from a three dimensional hyperspectral image stack. By moving a slider control, the user can easily move between images of the stack. The user can zoom into any region of the image. The user can select any pixel or region from themore » displayed image and display the fluorescence spectrum associated with that pixel or region. The user can define up to 3 spectral filters to apply to the hyperspectral image and view the image as it would appear from a filter-based confocal microscope. The user can also obtain statistics such as intensity average and variance from selected regions.« less

  3. Effects of Ti, V, and rare earth on the mechanical properties of austempered high silicon cast steel

    NASA Astrophysics Data System (ADS)

    Chen, Xiang; Li, Yanxiang

    2006-11-01

    The microstructure and mechanical properties of austempered high silicon cast steel pro and after treating with a modifier containing titanium, vanadium, and rare earth metals (so-called Ti-V-RE modifier) and austempered at different temperatures are investigated. The results show that the dendritic austempered structure and the blocky retained austenite are reduced after treating with the Ti-V-RE modifier. The modification can obviously improve the mechanical properties of austempered high silicon cast steel. The austempering temperature at which the optimum impact toughness is obtained shifts from about 320 °C for the steel unmodified to about 360 °C for the steel modified. High impact toughness is obtained in austempered high silicon cast steel high silicon cast steel when the retained austenite amount is about 15 to 25 pct for the modified steel and 20 to 35 pct for the unmodified steel.

  4. Interdiffusion Behavior in Aluminide Coatings for Power Generation Applications

    SciTech Connect

    Zhang, Y.; Pint, B.A.; Haynes, J.A.; Cooley, K.M.; Wright, I.G.

    2003-04-22

    One of the critical issues for the application of iron aluminide coatings is the loss of Al from the coating into the Fe-base substrate alloys which do not contain aluminum. The interdiffusion behavior between chemical vapor deposited (CVD) aluminide coatings and ferritic and austenitic substrates is being studied for times up to 10,000h in the temperature range of 500-800 C. Coatings were synthesized using a laboratory-scale CVD reactor on representative commercial ferritic (Fe-9Cr-1Mo) and austenitic (type 304L stainless steel) alloys. The aluminide coatings on both alloys typically consisted of a relatively thin (20-25 {micro}m) Al-rich outer layer and a thicker (150- 250 {micro}m) inner layer with less Al. The composition profiles before and after interdiffusion testing were measured by electron probe microanalysis (EPMA). The decrease of the Al content at the coating surface was not significant after extended diffusion times ({le} 5000h) at temperatures {le} 700 C. More interdiffusion occurred at 800 C in coatings on both Fe-9Cr-1Mo and 304L alloys. Particularly, a two-phase microstructure was formed in the outer coating layer on 304L after interdiffusion of 2000h at 800 C. The interdiffusion behavior also was simulated using a computer model COSIM (Coating Oxidation and Substrate Interdiffusion Model), which was originally developed for MCrAlY overlay coatings by NASA. Reasonable agreement was observed between the simulated and experimental composition profiles although more work is needed to confirm assumptions made in the model.

  5. Johnson-Cook Strength Model Constants for VascoMax 300 and 1080 Steels

    NASA Astrophysics Data System (ADS)

    Cinnamon, John D.; Brar, N. S.

    2005-07-01

    High strength steels, VascoMax 300 and 1080 steel, are characterized under tension at strain rates of ˜1/s, ˜500/s, ˜1000/s, and ˜1500/s and at high temperatures (1000°F for Vascomax 300 and 1080 steel to 750°F) using the quai-static and split Hopkinson bar techniques. The data on 1080 steel exhibit a strain hardening response, whereas VascoMax 300 steel showed diminishing flow stress beyond yielding because of localized necking in gauge section of the tested specimens. The tension data are analyzed to determine the Johnson-Cook (J-C) strength model constants for the two steels. The J-C model constants A, B, n, C, and m for 1080 steel are 0.514 GPa, 2.83 GPa, 0.612, 0.031, and 0.890, respectively. For Vascomax 300 steel A=2.07 GPa; B=1.98 GPa; n=0.416; C=0.006; m=1.425. The temperature softening constant ``m'' for Vascomax 300 steel show variation with strain rate and need to be reevaluated in view of its unusual behavior in declining flow stress above yielding. In addition, an analysis of the necking observed in the tested specimens of both the steels is presented.

  6. Pea Plants Show Risk Sensitivity.

    PubMed

    Dener, Efrat; Kacelnik, Alex; Shemesh, Hagai

    2016-07-11

    Sensitivity to variability in resources has been documented in humans, primates, birds, and social insects, but the fit between empirical results and the predictions of risk sensitivity theory (RST), which aims to explain this sensitivity in adaptive terms, is weak [1]. RST predicts that agents should switch between risk proneness and risk aversion depending on state and circumstances, especially according to the richness of the least variable option [2]. Unrealistic assumptions about agents' information processing mechanisms and poor knowledge of the extent to which variability imposes specific selection in nature are strong candidates to explain the gap between theory and data. RST's rationale also applies to plants, where it has not hitherto been tested. Given the differences between animals' and plants' information processing mechanisms, such tests should help unravel the conflicts between theory and data. Measuring root growth allocation by split-root pea plants, we show that they favor variability when mean nutrient levels are low and the opposite when they are high, supporting the most widespread RST prediction. However, the combination of non-linear effects of nitrogen availability at local and systemic levels may explain some of these effects as a consequence of mechanisms not necessarily evolved to cope with variance [3, 4]. This resembles animal examples in which properties of perception and learning cause risk sensitivity even though they are not risk adaptations [5]. PMID:27374342

  7. Casimir experiments showing saturation effects

    SciTech Connect

    Sernelius, Bo E.

    2009-10-15

    We address several different Casimir experiments where theory and experiment disagree. First out is the classical Casimir force measurement between two metal half spaces; here both in the form of the torsion pendulum experiment by Lamoreaux and in the form of the Casimir pressure measurement between a gold sphere and a gold plate as performed by Decca et al.; theory predicts a large negative thermal correction, absent in the high precision experiments. The third experiment is the measurement of the Casimir force between a metal plate and a laser irradiated semiconductor membrane as performed by Chen et al.; the change in force with laser intensity is larger than predicted by theory. The fourth experiment is the measurement of the Casimir force between an atom and a wall in the form of the measurement by Obrecht et al. of the change in oscillation frequency of a {sup 87}Rb Bose-Einstein condensate trapped to a fused silica wall; the change is smaller than predicted by theory. We show that saturation effects can explain the discrepancies between theory and experiment observed in all these cases.

  8. This photographic copy of an engineering drawing shows floor plans, ...

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

    This photographic copy of an engineering drawing shows floor plans, sections and elevations of Building E-86, with details typical of the steel frame and "Transite" building construction at JPL Edwards Facility. California Institute of Technology, Jet Propulsion Laboratory, Facilities Engineering and Construction Office: "Casting & Curing, Building E-86, Floor Plan, Elevations & Section," drawing no. E86/6, 25 February 1977. California Institute of Technology, Jet Propulsion Laboratory, Plant Engineering: engineering drawings of structures at JPL Edwards Facility. Drawings on file at JPL Plant Engineering, Pasadena, California - Jet Propulsion Laboratory Edwards Facility, Casting & Curing Building, Edwards Air Force Base, Boron, Kern County, CA

  9. Credit PSR. This view shows southeast and southwest facades as ...

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

    Credit PSR. This view shows southeast and southwest facades as seen when looking east northeast (70°). This steel frame building is clad in "Transite" board (fire- resistant, pressed asbestos composition board). This structure was built as a back-up to Building 4237/E-38, but no equipment was ever installed. It was equipped instead to conduct tensile tests on propellant samples. In 1984, it was converted into a back-up structure supporting Building 4283/E-84, Propellant Processing Building. Small amounts of HMX propellants were processed and dried here - Jet Propulsion Laboratory Edwards Facility, Oxidizer Dryer Blender Building, Edwards Air Force Base, Boron, Kern County, CA

  10. 91. View of scanner building No. 105 construction view showing ...

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

    91. View of scanner building No. 105 construction view showing upper (upper left) and (lower right) DR switches (note apertures for future waveguide connection) and structural steel support system. RCA Services Company 22 September, 1960, official photograph BMEWS Project by unknown photograph, Photographic Services, Riverton, NJ, BMEWS, clear as negative no. A-1219. - 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

  11. Strain limit dependence on stress triaxiality for pressure vessel steel

    NASA Astrophysics Data System (ADS)

    Deng, Y.-C.; Chen, G.; Yang, X.-F.; Xu, T.

    2009-08-01

    In this paper, the failure characteristics of pressure vessel materials were investigated, and measurement and analysis approaches for ductile fracture strains were studied. Based on uniaxial tensile tests of notched round bar specimens, combined with finite element analyses and microscopic observations of fracture surface, the relationships between the stress triaxiality factor and the ductile fracture strain are proposed for three typical Chinese pressure vessel steels, 16MnR, Q235 and 0Cr18Ni9. The comparison of experimental fracture strains with the multiaxial strain limit specified in ASME VIII-2 2007 shows that the strain limit criterion of ASME is suitable for carbon steels but not suitable for austenitic stainless steels for Chinese pressure vessel steels. To improve the calculation accuracy for fracture strain of materials and to develop the strain limit criterion for Chinese pressure vessel materials, more experimental studies and numerical analyses on fracture strain are necessary.

  12. Temperatures in Spark Plugs Having Steel and Brass Shells

    NASA Technical Reports Server (NTRS)

    Cragoe, C S

    1919-01-01

    This investigation was conducted at the Bureau of Standards for the National Advisory Committee for Aeronautics. Brass has often been assumed superior to steel for spark plug shells because of its greater heat conductivity. The measurements described in this report prove the contrary, showing that the interior of a spark plug having a brass shell is from 50 degrees to 150 degrees c. (90 degrees to 270 degrees f.) hotter than that of a similar steel plug. Consistent results were obtained in both an aviation and a truck engine, and under conditions which eliminated all other sources of difference between the plugs. It is to be concluded that steel is to be preferred to brass for spark plug shells. This report embodies the results of measurements taken of electrodes and a comparison of brass and steel insulators of spark plugs while they were in actual operation. The data throw considerable light upon the problem of the proper control of temperatures in these parts.

  13. 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.

  14. Structural characteristics and hydration kinetics of modified steel slag

    SciTech Connect

    Li Jianxin; Yu Qijun; Wei Jiangxiong Zhang Tongsheng

    2011-03-15

    This study investigates the structural characteristics and hydration kinetics of modified basic oxygen furnace steel slag. The basic oxygen furnace steel slag (BOFS) was mixed with electric arc furnace steel slag (EAFS) in appropriate ratios and heated again at high temperature in the laboratory. The mineralogical and structural characteristics of both BOFS and modified steel slag (MSS) were characterized by X-ray diffraction, optical microscopy, scanning electron microscopy, Raman and Fourier transform infrared spectroscopies. The results show that modification increases alite content in MSS and decreases alite crystal size with the formation of C{sub 6}AF{sub 2}. One more obvious heat evolution peak appears in MSS's heat-flow rate curves in comparison to BOFS, becoming similar to that of typical Portland cement paste. As a result, its cementitious activity is much improved.

  15. The industrial ecology of steel

    SciTech Connect

    Considine, Timothy J.; Jablonowski, Christopher; Considine, Donita M.M.; Rao, Prasad G.

    2001-03-26

    This study performs an integrated assessment of new technology adoption in the steel industry. New coke, iron, and steel production technologies are discussed, and their economic and environmental characteristics are compared. Based upon detailed plant level data on cost and physical input-output relations by process, this study develops a simple mathematical optimization model of steel process choice. This model is then expanded to a life cycle context, accounting for environmental emissions generated during the production and transportation of energy and material inputs into steelmaking. This life-cycle optimization model provides a basis for evaluating the environmental impacts of existing and new iron and steel technologies. Five different plant configurations are examined, from conventional integrated steel production to completely scrap-based operations. Two cost criteria are used to evaluate technology choice: private and social cost, with the latter including the environmental damages associated with emissions. While scrap-based technologies clearly generate lower emissions in mass terms, their emissions of sulfur dioxide and nitrogen oxides are significantly higher. Using conventional damage cost estimates reported in the literature suggests that the social costs associated with scrap-based steel production are slightly higher than with integrated steel production. This suggests that adopting a life-cycle viewpoint can substantially affect environmental assessment of new technologies. Finally, this study also examines the impacts of carbon taxes on steel production costs and technology choice.

  16. Morphological and microstructural studies on aluminizing coating of carbon steel

    SciTech Connect

    Samsu, Zaifol; Othman, Norinsan Kamil; Daud, Abd Razak; Hussein, Hishammuddin

    2013-11-27

    Hot dip aluminizing is one of the most effective methods of surface protection for steels and is gradually gaining popularity. The morphology and microstructure of an inter-metallic layer form on the surface of low carbon steel by hot dip aluminization treatment had been studied in detail. This effect has been investigated using optical and scanning electron microscopy, and X-ray diffraction. The result shows that the reaction between the steel and the molten aluminium leads to the formation of Fe–Al inter-metallic compounds on the steel surface. X-ray diffraction and electron microscopic studies showed that a two layer coating was formed consisting of an external Al layer and a (Fe{sub 2}Al{sub 5}) inter metallic on top of the substrate after hot dip aluminizing process. The inter-metallic layer is ‘thick’ and exhibits a finger-like growth into the steel. Microhardness testing shown that the intermetallic layer has high hardness followed by steel substrate and the lowest hardness was Al layer.

  17. Mimas Showing False Colors #1

    NASA Technical Reports Server (NTRS)

    2005-01-01

    False color images of Saturn's moon, Mimas, reveal variation in either the composition or texture across its surface.

    During its approach to Mimas on Aug. 2, 2005, the Cassini spacecraft narrow-angle camera obtained multi-spectral views of the moon from a range of 228,000 kilometers (142,500 miles).

    The image at the left is a narrow angle clear-filter image, which was separately processed to enhance the contrast in brightness and sharpness of visible features. The image at the right is a color composite of narrow-angle ultraviolet, green, infrared and clear filter images, which have been specially processed to accentuate subtle changes in the spectral properties of Mimas' surface materials. To create this view, three color images (ultraviolet, green and infrared) were combined into a single black and white picture that isolates and maps regional color differences. This 'color map' was then superimposed over the clear-filter image at the left.

    The combination of color map and brightness image shows how the color differences across the Mimas surface materials are tied to geological features. Shades of blue and violet in the image at the right are used to identify surface materials that are bluer in color and have a weaker infrared brightness than average Mimas materials, which are represented by green.

    Herschel crater, a 140-kilometer-wide (88-mile) impact feature with a prominent central peak, is visible in the upper right of each image. The unusual bluer materials are seen to broadly surround Herschel crater. However, the bluer material is not uniformly distributed in and around the crater. Instead, it appears to be concentrated on the outside of the crater and more to the west than to the north or south. The origin of the color differences is not yet understood. It may represent ejecta material that was excavated from inside Mimas when the Herschel impact occurred. The bluer color of these materials may be caused by subtle differences in

  18. Bioinspired steel surfaces with extreme wettability contrast

    NASA Astrophysics Data System (ADS)

    Her, Eun Kyu; Ko, Tae-Jun; Lee, Kwang-Ryeol; Oh, Kyu Hwan; Moon, Myoung-Woon

    2012-04-01

    The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on alloy steels by both nano-flake or needle patterns and tuning of the surface energy. Steels were provided with hierarchical micro/nanostructures of Fe oxides by fluorination and by a subsequent catalytic reaction of fluorine ions on the steel surfaces in water. A hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective regions surrounded by superhydrophobic surfaces. We show that wettability contrast surfaces align liquid water within patterned hydrophilic regions during the condensation process. Furthermore, this method could have a greater potential to align other liquids or living cells.The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on alloy steels by both nano-flake or needle patterns and tuning of the surface energy. Steels were provided with hierarchical micro/nanostructures of Fe oxides by fluorination and by a subsequent catalytic reaction of fluorine ions on the steel surfaces in water. A hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective

  19. Connections: Superplasticity, Damascus Steels, Laminated Steels, and Carbon Dating

    NASA Astrophysics Data System (ADS)

    Wadsworth, Jeffrey

    2016-09-01

    In this paper, a description is given of the connections that evolved from the initial development of a family of superplastic plain carbon steels that came to be known as Ultra-High Carbon Steels (UHCS). It was observed that their very high carbon contents were similar, if not identical, to those of Damascus steels. There followed a series of attempts to rediscover how the famous patterns found on Damascus steels blades were formed. At the same time, in order to improve the toughness at room temperature of the newly-developed UHCS, laminated composites were made of alternating layers of UHCS and mild steel (and subsequently other steels and other metals). This led to a study of ancient laminated composites, the motives for their manufacture, and the plausibility of some of the claims relating to the number of layers in the final blades. One apparently ancient laminated composite, recovered in 1837 from the great pyramid of Giza which was constructed in about 2750 B.C., stimulated a carbon dating study of ancient steels. The modern interest in "Bladesmithing" has connections back to many of these ancient weapons.

  20. Superior machinability of steel enhanced with BN and MnS particles

    NASA Astrophysics Data System (ADS)

    Chen, Ya-nan; Bao, Yan-ping; Wang, Min; Cai, Xiao-feng; Wang, Lin-jing; Zhao, Li-hua

    2016-03-01

    The strategy that replacing part of MnS with BN was proposed in order to decrease the sulfur content in sulfur based free-cutting steel. The effects of BN and MnS inclusions on the microstructure and machinability of the steel were systematically investigated. The results show that most of the BN and MnS inclusions exist individually in the steel and only a small amount of them are in a composite state forming either isolated particles or clusters of particles. In the case of multi-phased steel, the theoretical calculation predicts that the volume of large BN particles should be 0.7 times of the volume of large MnS particles. The machinability of this type of BN and MnS alloy steel over a wide range of cutting speeds ranging from a low speed appropriate for drilling to a high speed appropriate for turning is confirmed as being equal to or superior to that of an MnS reference steel, even though the sulfur content in the composite steel is only half that of the MnS steel. The aptitude for cutting effect of 240 ppm nitrogen and 115 ppm boron in the composite steel is demonstrated to be equivalent or even better than 1000 ppm sulfur in MnS free-cutting steel.

  1. A discussion on improving hydration activity of steel slag by altering its mineral compositions.

    PubMed

    Wang, Qiang; Yan, Peiyu; Feng, Jianwen

    2011-02-28

    This study aims to investigate the ways to improve the cementitious properties of steel slag. The results show that the cementitious phase of steel slag is composed of silicate and aluminate, but the large particles of these phases make a very small contribution to the cementitious properties of steel slag. RO phase (CaO-FeO-MnO-MgO solid solution), Fe(3)O(4), C(2)F and f-CaO make no contribution to the cementitious properties of steel slag. A new kind of steel slag with more cementitious phase and less RO phase can be obtained by removing some large particles. This new steel slag possesses better cementitious properties than the original steel slag. The large particles can be used as fine aggregates for concrete. Adding regulating agent high in CaO and SiO(2) during manufacturing process of steel slag to increase the cementitious phase to inert phase ratio is another way to improve its cementitious properties. The regulating agent should be selected to adapt to the specific steel slag and the alkalinity should be increased as high as possible on the premise that the f-CaO content does not increase. The cooling rate should be enhanced to improve the hydration activity of the cementitious phase at the early ages and the grindability of steel slag.

  2. Phase Transformation in Cast Superaustenitic Stainless Steels

    SciTech Connect

    Lee Phillips, Nathaniel Steven

    2006-01-01

    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.

  3. 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.

  4. Weldability of Additive Manufactured Stainless Steel

    NASA Astrophysics Data System (ADS)

    Matilainen, Ville-Pekka; Pekkarinen, Joonas; Salminen, Antti

    Part size in additive manufacturing is limited by the size of building area of AM equipment. Occasionally, larger constructions that AM machines are able to produce, are needed, and this creates demand for welding AM parts together. However there is very little information on welding of additive manufactured stainless steels. The aim of this study was to investigate the weldability aspects of AM material. In this study, comparison of the bead on plate welds between AM parts and sheet metal parts is done. Used material was 316L stainless steel, AM and sheet metal, and parts were welded with laser welding. Weld quality was evaluated visually from macroscopic images. Results show that there are certain differences in the welds in AM parts compared to the welds in sheet metal parts. Differences were found in penetration depths and in type of welding defects. Nevertheless, this study presents that laser welding is suitable process for welding AM parts.

  5. 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.

  6. Hydrogen retention in ion irradiated steels

    SciTech Connect

    Hunn, J.D.; Lewis, M.B.; Lee, E.H.

    1998-11-01

    In the future 1--5 MW Spallation Neutron Source, target radiation damage will be accompanied by high levels of hydrogen and helium transmutation products. The authors have recently carried out investigations using simultaneous Fe/He,H multiple-ion implantations into 316 LN stainless steel between 50 and 350 C to simulate the type of radiation damage expected in spallation neutron sources. Hydrogen and helium were injected at appropriate energy and rate, while displacement damage was introduced by nuclear stopping of 3.5 MeV Fe{sup +}, 1 {micro}m below the surface. Nanoindentation measurements showed a cumulative increase in hardness as a result of hydrogen and helium injection over and above the hardness increase due to the displacement damage alone. TEM investigation indicated the presence of small bubbles of the injected gases in the irradiated area. In the current experiment, the retention of hydrogen in irradiated steel was studied in order to better understand its contribution to the observed hardening. To achieve this, the deuterium isotope ({sup 2}H) was injected in place of natural hydrogen ({sup 1}H) during the implantation. Trapped deuterium was then profiled, at room temperature, using the high cross-section nuclear resonance reaction with {sup 3}He. Results showed a surprisingly high concentration of deuterium to be retained in the irradiated steel at low temperature, especially in the presence of helium. There is indication that hydrogen retention at spallation neutron source relevant target temperatures may reach as high as 10%.

  7. Boundary effects in welded steel moment connections

    NASA Astrophysics Data System (ADS)

    Lee, Kyoung-Hyeog

    Unprecedented widespread failure of welded moment connections in steel frames caused by the 1994 Northridge and the 1995 Kobe earthquakes have alarmed the engineering communities throughout the world. Welded moment connections in steel frames have been traditionally designed by using the classical beam theory which leads to assumptions that the flanges transfer moment while the web connection primarily resists the shear force. However, this study shows that the magnitude and direction of the principal stresses in the connection region are better approximated by using truss analogy rather than the classical beam theory. Accordingly, both the bending moment and the shear force are transferred across the connection near the beam flanges through diagonal strut action. Thus, the beam flange region of the traditionally designed connection is overloaded. This conclusion explains, to a large extent, the recently observed steel moment connection failures. In this study, detailed finite element analyses were carried out for a representative beam-to-column subassemblage with fully welded connection. The stress distribution in the beam web and flanges in the vicinity of the connection were closely studied. The factors responsible for stress redistribution and concentration were identified by using fundamental principles of mechanics. It was concluded that peak resultant stresses can exceed the values used in simple design calculations by large margins. Using the finite element analysis results and the truss analogy to establish a realistic load path in the connection, a practical and more rational analysis and design procedure was developed. The proposed design procedure and the new connection details were successfully validated through cyclic load testing of a nearly full size specimen. The truss model represented the force transmission around the beam-to-column moment connection region very well. Results of the finite element analyses and the laboratory testing showed

  8. Occupational Profiles in the European Steel Industry.

    ERIC Educational Resources Information Center

    Franz, Hans-Werner; And Others

    The steel industry in Europe has faced great changes, with resulting layoffs and restructuring. Now that the most basic changes seem to be over, it has become evident that the remaining steel industry requires more highly trained workers than was the case previously. Although steel maintenance employees were always highly skilled, steel production…

  9. Improving the toughness of ultrahigh strength steel

    SciTech Connect

    Soto, Koji

    2002-08-15

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors.

  10. Improving the toughness of ultrahigh strength steel

    NASA Astrophysics Data System (ADS)

    Sato, Koji

    2002-01-01

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors. Chapter 1 reviews the mechanical properties of ultrahigh strength steels and the physical metallurgy of AerMet 100. It also describes the fracture mechanisms of steel, i.e. ductile microvoid coalescence, brittle transgranular cleavage, and intergranular separation. Chapter 2 examines the strength-toughness relationship for three heats of AerMet 100. A wide variation of toughness is obtained at the same strength level. The toughness varies despite the fact that all heat fracture in the ductile fracture mode. The difference originates from the inclusion content. Lower inclusion volume fraction and larger inclusion spacing gives rise to a greater void growth factor and subsequently a higher fracture toughness. The fracture toughness value, JIc, is proportional to the particle spacing of the large non-metallic inclusions. Chapter 3 examines the ductile-brittle transition of AerMet 100 and the effect of a higher austenitization temperature, using the Charpy V-notch test. The standard heat treatment condition of AerMet 100 shows a gradual ductile-brittle transition due to its fine effective grain size. Austenitization at higher temperature increases the prior austenite grain size and packet size, leading to a steeper transition at a higher temperature. Both transgranular cleavage and intergranular separation are observed in the brittle fracture mode. Chapter 4 examines the effect of inclusion content, prior austenite grain size, and the amount of austenite on the strength-toughness relationship. The highest toughness is achieved by low inclusion content, small prior austenite grain size

  11. Machining of Christmas tree parts of 06Kh20N8M3D2L corrosion-resistant steel

    SciTech Connect

    Rubinov, S.R.; Balaoglanov, M.M.; Baluyants, E.G.

    1983-09-01

    To address the problem of corrosion cracking, equipment has been developed of 06Kh20N8M3D21 austenitic-ferritic corrosion-resistant multiply alloyed steel. But as this steel is difficult to machine investigations were made to determine the parameters and conditions for machining Christmas tree parts made of this steel. Turning, drilling, thread cutting, and milling are specified. The optimum conditions for machining Christmas tree parts were established in tests. The tests also showed that the coefficient of machinability of the steel is 3 or 4 times less than that of 20KhGSL steel, which is normally used for Christmas tree production.

  12. Phosphorus removal by electric arc furnace steel slag and serpentinite.

    PubMed

    Drizo, Aleksandra; Forget, Christiane; Chapuis, Robert P; Comeau, Yves

    2006-05-01

    Electric arc furnace (EAF) steel slag and serpentinite were tested in columns either alone or mixed with limestone to determine their capacity to remove phosphorus (P) from a solution containing initially 20mg P/L (for 114 days) than 400mg P/L (for 21 days). EAF steel slag was nearly 100% efficient due to specific P adsorption onto metal hydroxides and precipitation of hydroxyapatite. Serpentinite also showed a good performance that decreased with time, adsorption appearing to be the dominant mechanism for P removal. Mixing limestone with these two materials did not improve their performance and in the case of serpentinite, it actually even decreased it. In 114 days of experimentation, serpentinite alone and the mixture of serpentinite and limestone removed 1.0mg P/g while in 180 days of experimentation, EAF steel slag and the mixture of slag and limestone removed an average of 2.2mg P/g, without attaining their maximum P removal potential. The void hydraulic retention time (HRTv) was a key factor for growing hydroxyapatite crystals and had a significant effect on P removal efficiency by EAF steel slag. A temporary increase in HRTv caused by clogging resulted in an increase in EAF steel slag efficiency (from 80% to almost 100%) towards the end of investigation. Results from this study indicate that the use of EAF steel slag in constructed wetlands or filter beds is a promising solution for P removal via adsorption and precipitation mechanisms.

  13. Effect of temperature on the passivation behavior of steel rebar

    NASA Astrophysics Data System (ADS)

    Chen, Shan-meng; Cao, Bei; Wu, Yin-shun; Ma, Ke

    2014-05-01

    Steel rebar normally forms an oxide or rusty skin before it is embedded into concrete and the passivation properties of this skin will be heavily influenced by temperature. To study the effect of temperature on the passivation properties of steel rebar under different surface conditions, we conducted scanning electron microscopy (SEM) observations and electrochemical measurements, such as measurements of the free corrosion potential and polarization curves of HPB235 steel rebar. These measurements identified three kinds of surfaces: polished, oxide skin, and rusty skin. Our results show that the passivation properties of all the surface types decrease with the increase of temperature. Temperature has the greatest effect on the rusty-skin rebar and least effect on the polished steel rebar, because of cracks and crevices on the mill scale on the steel rebar's surface. The rusty-skin rebar exhibits the highest corrosion rate because crevice corrosion can accelerate the corrosion of the steel rebar, particularly at high temperature. The results also indicate that the threshold temperatures of passivation for the oxide-skin rebar and the rusty-skin rebar are 37°C and 20°C, respectively.

  14. 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.

  15. Development of third generation advanced high strength steels

    NASA Astrophysics Data System (ADS)

    McGrath, Meghan Colleen

    Lightweight duplex steels with combinations of either bainite, acicular ferrite, and austenite or martensite and austenite were investigated as third generation advanced high strength steels targeted for automotive applications. Large additions of manganese (> 13 wt%) and carbon (<0.2wt%) were employed to stabilize the austenite phase. Silicon additions between 1 and 2 wt% were added to suppress cementite formation. Strength and ductility were increased while density was decreased with aluminum additions between 2.4 and 5.5 wt% to the steel. This research addressed the dependence of alloying on microstructures and mechanical behavior for high manganese and aluminum duplex steels that were cast and subsequently hot rolled. Duplex steels with different volume fractions of primary delta-ferrite were used to study the crystallography of austenite fanned during the peritectic reaction. Solute profiles across the peritectic interface showed aluminum segregated near the interface which promoted bainitic ferrite formation. Thermal treatments were used to manipulate the concentration and type of oxides and the ferrite plate density was found to correlate with inclusions of low misfit in steels with austenite grain size of 16.5 microm. A steel with bainite and acicular ferrite produced an ultimate tensile strength of 970 MPa and elongation of 40%. The mechanical prope1iies depended on the strengths and size of the microstructural constituents. Work hardening behavior was examined in a steel exhibiting multiple martensitic transformation induced plasticity (gamma-austenite→epsilon-smartensite→alpha-martensite). A strain hardening exponent as high as 1.4 was observed with ultimate tensile strength and elongation as high as 1,165 MPa and 34%.

  16. Influence of Martensite Volume Fraction on Impact Properties of Triple Phase (TP) Steels

    NASA Astrophysics Data System (ADS)

    Zare, Ahmad; Ekrami, A.

    2013-03-01

    Ferrite-bainite-martensite triple phase (TP) microstructures with different volume fractions of martensite were obtained by changing heat treatment time during austempering at 300 °C. Room temperature impact properties of TP steels with different martensite volume fractions ( V M) were determined by means of Charpy impact testing. The effects of test temperature on impact properties were also investigated for two selected microstructures containing 0 (the DP steel) and 8.5 vol.% martensite. Test results showed reduction in toughness with increasing V M in TP steels. Fracture toughness values for the DP and TP steels with 8.5 vol.% martensite were obtained from correlation between fracture toughness and the Charpy impact energy. Fractography of Charpy specimens confirmed decrease in TP steels' toughness with increasing V M by considering and comparing radial marks and crack initiation regions at the fracture surfaces of the studied steels.

  17. Upset Resistance Welding of Carbon Steel to Austenitic Stainless Steel Narrow Rods

    NASA Astrophysics Data System (ADS)

    Ozlati, Ashkaan; Movahedi, Mojtaba; Mohammadkamal, Helia

    2016-09-01

    Effects of welding current (at the range of 2-4 kA) on the microstructure and mechanical properties of upset resistance welds of AISI-1035 carbon steel to AISI-304L austenitic stainless steel rods were investigated. The results showed that the joint strength first increased by raising the welding current up to 3 kA and then decreased beyond it. Increasing trend was related to more plastic deformation, accelerated diffusion, reduction of defects and formation of mechanical locks at the joint interface. For currents more than 3 kA, decrease in the joint strength was mainly caused by formation of hot spots. Using the optimum welding current of 3 kA, tensile strength of the joint reached to ~76% of the carbon steel base metal strength. Microstructural observations and microhardness results confirmed that there was no hard phase, i.e., martensite or bainite, at the weld zone. Moreover, a fully austenitic transition layer related to carbon diffusion from carbon steel was observed at the weld interface.

  18. Report on sodium compatibility of advanced structural materials.

    SciTech Connect

    Li, M.; Natesan, K.; Momozaki, Y.; Rink, D.L.; Soppet, W.K.; Listwan, J.T.

    2012-07-09

    This report provides an update on the evaluation of sodium compatibility of advanced structural materials. The report is a deliverable (level 3) in FY11 (M3A11AN04030403), under the Work Package A-11AN040304, 'Sodium Compatibility of Advanced Structural Materials' performed by Argonne National Laboratory (ANL), as part of Advanced Structural Materials Program for the Advanced Reactor Concepts. This work package supports the advanced structural materials development by providing corrosion and tensile data from the standpoint of sodium compatibility of advanced structural alloys. The scope of work involves exposure of advanced structural alloys such as G92, mod.9Cr-1Mo (G91) ferritic-martensitic steels and HT-UPS austenitic stainless steels to a flowing sodium environment with controlled impurity concentrations. The exposed specimens are analyzed for their corrosion performance, microstructural changes, and tensile behavior. Previous reports examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design, fabrication, and construction of a forced convection sodium loop for sodium compatibility studies of advanced materials. This report presents the results on corrosion performance, microstructure, and tensile properties of advanced ferritic-martensitic and austenitic alloys exposed to liquid sodium at 550 C for up to 2700 h and at 650 C for up to 5064 h in the forced convection sodium loop. The oxygen content of sodium was controlled by the cold-trapping method to achieve {approx}1 wppm oxygen level. Four alloys were examined, G92 in the normalized and tempered condition (H1 G92), G92 in the cold-rolled condition (H2 G92), G91 in the normalized and tempered condition, and hot-rolled HT-UPS. G91 was included as a reference to compare with advanced alloy, G92. It was found that all four alloys showed weight loss after sodium exposures at 550 and 650 C. The weight loss of the four

  19. 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

  20. 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.

  1. Advanced steel reheat furnace

    SciTech Connect

    Moyeda, D.; Sheldon, M.; Koppang, R.; Lanyi, M.; Li, X.; Eleazer, B.

    1997-10-01

    Energy and Environmental Research Corp. (EER) under a contract from the Department of Energy is pursuing the development and demonstration of an Advanced Steel Reheating Furnace. This paper reports the results of Phase 1, Research, which has evaluated an advanced furnace concept incorporating two proven and commercialized technologies previously applied to other high temperature combustion applications: EER`s gas reburn technology (GR) for post combustion NOx control; and Air Product`s oxy-fuel enrichment air (OEA) for improved flame heat transfer in the heating zones of the furnace. The combined technologies feature greater production throughput with associated furnace efficiency improvements; lowered NOx emissions; and better control over the furnace atmosphere, whether oxidizing or reducing, leading to better control over surface finish.

  2. Corrosion of Steels in Steel Reinforced Concrete in Cassava Juice

    NASA Astrophysics Data System (ADS)

    Oluwadare, G. O.; Agbaje, O.

    The corrosion of two types of construction steels, ST60Mn and RST37-2♦, in a low cyanide concentration environment (cassava juice) and embedded in concrete had been studied. The ST60 Mn was found to be more corrosion resistant in both ordinary water and the cassava juice environment. The cyanide in cassava juice does not attack the steel but it provides an environment of lower pH around the steel in the concrete which leads to breakdown of the passivating film provided by hydroxyl ions from cement. Other factors such as the curing time of the concrete also affect the corrosion rates of the steel in the concrete. The corrosion rate of the steel directly exposed to cassava juice i.e., steel not embedded in concrete is about twice that in concrete. Long exposure of concrete structure to cassava processing effluent might result in deterioration of such structures. Careful attention should therefore be paid to disposal of cassava processing effluents, especially in a country like Nigeria where such processing is now on the increase.

  3. Stiffness of Railway Soil-Steel Structures

    NASA Astrophysics Data System (ADS)

    Machelski, Czesław

    2015-12-01

    The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness) become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces), as in bridges. The analyzed cases show that the shell's span, geometry (static scheme) and the height of earth fill influence the stiffness of the structure. The soil-steel structure's characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  4. Strength gradient enhances fatigue resistance of steels

    NASA Astrophysics Data System (ADS)

    Ma, Zhiwei; Liu, Jiabin; Wang, Gang; Wang, Hongtao; Wei, Yujie; Gao, Huajian

    2016-02-01

    Steels are heavily used in infrastructure and the transportation industry, and enhancing their fatigue resistance is a major challenge in materials engineering. In this study, by introducing a gradient microstructure into 304 austenitic steel, which is one of the most widely used types of stainless steel, we show that a strength gradient substantially enhances the fatigue life of the material. Pre-notched samples with negative strength gradients in front of the notch’s tip endure many more fatigue cycles than do samples with positive strength gradients during the crack initiation stage, and samples with either type of gradient perform better than do gradient-free samples with the same average yield strength. However, as a crack grows, samples with positive strength gradients exhibit better resistance to fatigue crack propagation than do samples with negative gradients or no gradient. This study demonstrates a simple and promising strategy for using gradient structures to enhance the fatigue resistance of materials and complements related studies of strength and ductility.

  5. Strength gradient enhances fatigue resistance of steels

    PubMed Central

    Ma, Zhiwei; Liu, Jiabin; Wang, Gang; Wang, Hongtao; Wei, Yujie; Gao, Huajian

    2016-01-01

    Steels are heavily used in infrastructure and the transportation industry, and enhancing their fatigue resistance is a major challenge in materials engineering. In this study, by introducing a gradient microstructure into 304 austenitic steel, which is one of the most widely used types of stainless steel, we show that a strength gradient substantially enhances the fatigue life of the material. Pre-notched samples with negative strength gradients in front of the notch’s tip endure many more fatigue cycles than do samples with positive strength gradients during the crack initiation stage, and samples with either type of gradient perform better than do gradient-free samples with the same average yield strength. However, as a crack grows, samples with positive strength gradients exhibit better resistance to fatigue crack propagation than do samples with negative gradients or no gradient. This study demonstrates a simple and promising strategy for using gradient structures to enhance the fatigue resistance of materials and complements related studies of strength and ductility. PMID:26907708

  6. Subsurface electromagnetic measurement through steel casing

    SciTech Connect

    Becker, A.B.; Wang, B.; Lee, K.H.

    1998-11-01

    Numerical calculations show that useful information can be obtained in an electromagnetic crosswell survey where one of the wells is cased in steel. Our simple model is based on the assumption of an infinitely long uniform casing embedded in a homogeneous full space. Nevertheless the results indicate that if the pipe characteristics are independently known then the formation signal can be accurately recovered. This is best done at a single frequency where the pipe attenuation is modest. In fact we show that the optimal frequency for formation signal recovery is defined mainly by the pipe parameters and is largely independent of the formation conductivity.

  7. Nickel-chromium plasma spray coatings: A way to enhance degradation resistance of boiler tube steels in boiler environment

    NASA Astrophysics Data System (ADS)

    Sidhu, Buta Singh; Prakash, S.

    2006-03-01

    Boiler tube steels, namely low carbon steel ASTM-SA-210-Grades A1 (GrA1), 1Cr-0.5Mo steel ASTM-SA213-T-11 (T11), and 2.25Cr-1 Mo steel ASTM-SA213-T-22(T22), were used as substrate steels. Ni-22Cr-10Al-1Y powder was sprayed as a bond coat 150 μm thick before a 200 μm final coating of Ni-20Cr was applied Coatings were characterized prior to testing in the environment of a coal fire boiler. The uncoated and coated steels were inserted in the platen superheater zone of a coal fired boiler at around 755°C for 10 cycles, each 100 h. Coated steels showed lower degradation (erosion-corrosion) rate than uncoated steels showed. The lowest rate was observed in the case of Ni-20Cr coated T11 steel. Among the uncoated steels, the observed rate of degradation was the lowest for the T22 steel.

  8. Bauschinger effect and springback behavior of dual phase sheet steels

    NASA Astrophysics Data System (ADS)

    Ma, Hongwei

    2007-09-01

    With the increasing use of advanced high strength steels in the automotive industry, springback control has become a more critical issue. It is now realized that a more accurate simulation of springback has to take the Bauschinger effect into account, especially when sheet experiences complicated plastic deformation. In this study, the Bauschinger effect in dual-phase (DP) steels was investigated through tension-unloading-reloading tests. Fundamental mechanisms of the Bauschinger effect were examined via two special experiments: (i) TEM study of the dislocation distribution at the different plastic pre-strains in Bauschinger tests; and (ii) residual stress measurement after different tensile strains using in-situ neutron diffraction technology. To investigate the influence of the Bauschinger effect on springback, deep-draw bending tests were carried out with the different friction conditions. The experimental results of the tension-unloading-reloading tests show the Bauschinger effect in DP steel is much stronger than that in interfacial-free (IF) steel. TEM observation revealed very strong interactions between dislocations and martensite in DP steels. In-situ neutron diffraction tests show that the residual strains caused by inhomogeneous deformation of the two phases in DP steel after deformation are much higher than those in IF steels. The above results support the observation of a strong Bauschinger effect in DP steels. A composite model based on the analysis of internal stress shows further clearly that the residual stresses are the predominant mechanism of the Bauschinger effect in DP steels. A newly defined Bauschinger energy parameter (E beta) was found to be able to quantitatively describe this transient softening before reversed loading. The unloading responses showed the total recovery comes not only from elastic recovery but also from inelastic recovery. An effective unloading modulus was therefore introduced to reflect the inelastic recovery. Based on

  9. Metal Penetration in Sand Molds for Steel Castings: Annual Report

    SciTech Connect

    Barlow, J.O.; Stefanescu, D.M.; Lane, A.M.; Schreiber, W.C.; Owens, M.; Piwonka, T.S.

    1996-04-01

    Case studies of samples of penetration provided by consortium members showed examples of mechanical-type penetration defects and of what appeared to be chemical penetration. Sessile drop experiments of various mold substrate materials using carbon, stainless, and Mn steels showed that Mn steel wets silica strongly, indicating that silica is not a suitable mod material for this family of alloys. Contact angles were lower for steels than for cast irons. Magnesite appeared to be the best overall mold material, although zircon flour also performed well. A simplified 1-D model was developed which predicts the diffusion rates which could cause chemical penetration. It shows that, contrary to the case in cast iron, chemical penetration is a possibility in medium and low carbon steels, as diffusion of C to the casting surface may not always occur quickly enough to protect the surface from an oxidizing reaction. The mass spectrometer gas chromatograph train was modified for accurately determining the water content of gas at the mold/metal interface. Initial gas measurements indicated that the gas generated at the interface in steel castings is 80% H2-20% CO, instead of the 50% H2- 50% CO mixture found in cast iron.

  10. Effects of Manganese Content on Solidification Structures, Thermal Properties, and Phase Transformation Characteristics in Fe-Mn-C Steels

    NASA Astrophysics Data System (ADS)

    Yang, Jian; Wang, Yu-Nan; Ruan, Xiao-Ming; Wang, Rui-Zhi; Zhu, Kai; Fan, Zheng-Jie; Wang, Ying-Chun; Li, Cheng-Bin; Jiang, Xiao-Fang

    2015-02-01

    The solidification structures and the thermal properties of Fe-Mn-C steel ingots containing different manganese contents have been investigated and the phase transformation characteristics have been revealed by Thermo-Calc to assist development of the continuous casting technology of Fe-Mn-C steels. The results show that the thermal conductivity of the 0Mn steel is higher than that of the 3Mn steel. The thermal conductivity of the 6Mn steel is the lowest in the three kinds of steels below 1023 K (750 °C) and the highest above 1173 K (900 °C). The 0Mn steel has the highest value of the proportion of equiaxed grain zone area in the three kinds of steels, whereas the 3Mn steel has the lowest value of it in the steels. Manganese has the effect of promoting the coarsening of grains. The microstructure is martensite and a little retained austenite (3.8 mass pct) in the 6Mn steel, whereas the microstructure is bainite in the 3Mn steel. The 0Mn steel is characterized by ferrite and pearlite. The mean thermal expansion coefficients of the steels are in the range from 1.0 × 10-5 to 1.6 × 10-5 K-1, and the determinations of mold tapers of the 6Mn and 3Mn steels can refer to low-carbon steel. Using RA <60 pct as the criterion, the third brittle temperature region of the 6Mn steel is 873 K to 1073 K (600 °C to 800 °C), whereas those of the 3Mn steel and the 0Mn steel are 873 K to 1123 K (600 °C to 850 °C) and 873 K to 1173 K (600 °C to 900 °C), respectively. In the 6Mn and 3Mn steels, the deformation-induced ferrite (DIF) forms in sufficient quantities cause the recovery of the ductility at the low temperature end. However, since low strains are present when straightening, sufficient quantities of DIF cannot be formed. Thus, the ductility of the 6Mn and 3Mn steels cannot be improved during the continuous casting process. Manganese has the effect of enlarging the austenite phase region and reducing the δ-ferrite phase region and α-ferrite phase region.

  11. Great Lakes Steel -- PCI facility

    SciTech Connect

    Eichinger, F.T.; Dake, S.H.; Wagner, E.D.; Brown, G.S.

    1997-12-31

    This paper discusses the planning, design, and start-up of the 90 tph PCI facility for National Steel`s Great Lakes Steel Division in River Rouge, MI. This project is owned and operated by Edison Energy Services, and was implemented on a fast-track basis by Raytheon Engineers and Constructors, Babcock Material Handling, and Babcock and Wilcox. This paper presents important process issues, basic design criteria, an the challenges of engineering and building a state-of-the-art PCI facility in two existing plants. Pulverized coal is prepared at the River Rouge Power Plant of Detroit Edison, is pneumatically conveyed 6,000 feet to a storage silo at Great Lakes Steel, and is injected into three blast furnaces.

  12. Hydrogen embrittlement of structural steels.

    SciTech Connect

    Somerday, Brian P.

    2010-06-01

    Carbon-manganese steels are candidates for the structural materials in hydrogen gas pipelines, however it is well known that these steels are susceptible to hydrogen embrittlement. Decades of research and industrial experience have established that hydrogen embrittlement compromises the structural integrity of steel components. This experience has also helped identify the failure modes that can operate in hydrogen containment structures. As a result, there are tangible ideas for managing hydrogen embrittement in steels and quantifying safety margins for steel hydrogen containment structures. For example, fatigue crack growth aided by hydrogen embrittlement is a key failure mode for steel hydrogen containment structures subjected to pressure cycling. Applying appropriate structural integrity models coupled with measurement of relevant material properties allows quantification of safety margins against fatigue crack growth in hydrogen containment structures. Furthermore, application of these structural integrity models is aided by the development of micromechanics models, which provide important insights such as the hydrogen distribution near defects in steel structures. The principal objective of this project is to enable application of structural integrity models to steel hydrogen pipelines. The new American Society of Mechanical Engineers (ASME) B31.12 design code for hydrogen pipelines includes a fracture mechanics-based design option, which requires material property inputs such as the threshold for rapid cracking and fatigue crack growth rate under cyclic loading. Thus, one focus of this project is to measure the rapid-cracking thresholds and fatigue crack growth rates of line pipe steels in high-pressure hydrogen gas. These properties must be measured for the base materials but more importantly for the welds, which are likely to be most vulnerable to hydrogen embrittlement. The measured properties can be evaluated by predicting the performance of the pipeline

  13. Wear of steel by rubber

    NASA Technical Reports Server (NTRS)

    Gent, A. N.; Pulford, C. T. R.

    1978-01-01

    Wear of a steel blade used as a scraper to abrade rubber surfaces has been found to take place much more rapidly on a cis-polyisoprene (natural rubber) surface than on a cis-polybutadiene surface, and much more rapidly in an inert atmosphere than in air. These observations are attributed to the direct attack upon steel of free-radical species generated by mechanical rupture of elastomer molecules during abrasion.

  14. Fatigue handbook: Offshore steel structures

    SciTech Connect

    Almarnaess, A.

    1985-01-01

    The contents of this book are: Overview of Offshore Steel Structures; Loads on Ocean Structures; Fracture Mechanics As a Tool in Fatigue Analysis; Basic Fatigue Properties of Welded Joints; Significance of Defects; Improving the Fatigue Strength of Welded Joints; Effects of Marine Environment and Cathodic Protection on Fatigue of Structural Steels Fatigue of Tubular Joints; Unstable Fracture; Fatigue Life Calculations; and Fatigue in Building Codes Background and Applications.

  15. 65. Neg. No. F99, Dec 27, 1931, INTERIORPRESSED STEEL BUILDING ...

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

    65. Neg. No. F-99, Dec 27, 1931, INTERIOR-PRESSED STEEL BUILDING FACING SOUTH TOWARD WAREHOUSE AND ASSEMBLY BUILDING 1ST FLOOR, EAST SIDE FACING SOUTH, SHOWING PRESSED STEEL MACHINERY AND RAILROAD CARS - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  16. 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.

  17. Surface Nb-ALLOYING on 0.4C-13Cr Stainless Steel: Microstructure and Tribological Behavior

    NASA Astrophysics Data System (ADS)

    Yu, Shengwang; You, Kai; Liu, Xiaozhen; Zhang, Yihui; Wang, Zhenxia; Liu, Xiaoping

    2016-02-01

    0.4C-13Cr stainless steel was alloyed with niobium using double glow plasma surface alloying and tribological properties of Nb-alloyed steel such as hardness, friction and wear were measured. Effects of the alloying temperature on microstructure and the tribological behavior of the alloyed steel were investigated compared with untreated steel. Formation mechanisms of Nb-alloyed layers and increased wear resistance were also studied. The result shows that after surface Nb-alloying treatment, the 0.4C-13Cr steel exhibits a diffusion adhesion at the alloyed layer/substrate interface and improved tribological property. The friction coefficient of Nb-alloyed steel is decreased by about 0.3-0.45 and the wear rate after Nb-alloying is only 2-5% of untreated steel.

  18. Improved Austenitic Steels for Power Plant Applications

    SciTech Connect

    Alman, David E.; Dunning, John S.; Schrems, Karol K.; Rawers, James C.; Wilson, Rick D.; Hawk, Jeffrey A.; Petty, Arthur V., Jr.

    2002-08-06

    Using alloy design principles, an austenitic alloy, with base composition of Fe-16Cr-16Ni-2Mn-1Mo (in weight percent, wt%), was formulated to which up to 5 wt% Si and/or Al were added specifically to improve the oxidation resistance. Cyclic oxidation tests were carried out in air at 700 and 800 C for 1000 hours. For comparison, Fe-18Cr-8Ni type-304 stainless steel alloys was also tested. The results showed that at 700 C, all the alloys were twice as oxidation resistant as the type-304 alloy (i.e., the experimental alloys showed weight gains about half that of type-304). Surprisingly, at 800 C, alloys that contained both Al and Si additions were less oxidation resistant than the type-304 alloy. However, alloys containing only Si additions were significantly more oxidation resistant than the type 304 alloys (i.e., showed weight gains 4 times less than the type-304 alloy). Further, alloys with only Si additions pre-oxidized at 800 C, showed zero weight gain in subsequent testing for 1000 hours at 700 C. This implies the potential for producing in-situ protective coating for these alloys. Preliminary exposure tests (1%H2S at 700 C for 360 hrs) indicated that the Si-modified alloys are more sulfidation resistant than type-304 alloy. The mechanical properties of the alloys, modified with carbide forming elements, were also evaluated; and at 600, 700 and 800 C the yield stresses of the carbide modified alloys were twice that of type-304 stainless steel. In this temperature range, the tensile properties of these alloys were comparable to literature values for type-347 stainless steel. It should be emphasized that the microstructures of the carbide forming alloys were not optimized with respect to grain size, carbide size and/or carbide distribution. Also, presented are initial results of vari-strain weld tests used to determine parameters for joining these alloys.

  19. Corrosion fatigue behavior of low alloy steels under simulated BWR coolant conditions

    NASA Astrophysics Data System (ADS)

    Huang, J. Y.; Young, M. C.; Jeng, S. L.; Yeh, J. J.; Huang, J. S.; Kuo, R. C.

    2010-10-01

    The corrosion fatigue crack growth behavior of A533 and A508 low alloy steels under simulated boiling water reactor (BWR) coolant conditions was studied. Corrosion fatigue crack growth rates of A533B3 and A508 cl. 3 steels were significantly affected by the steel sulfur content, loading frequency and dissolved oxygen content of water environments. The data points outside the bound of Eason's model could be attributed to the low frequency, higher steel sulfur content and high dissolved oxygen in water environments. The sulfur dissolved in the water environment from the higher-sulfur steels was sufficiently concentrated to acidify the crack tip chemistry even in the hydrogen water chemistry (HWC). Therefore, nitrogenated or HWC water showed little or no beneficiary effect on the high-sulfur steels. For the steel specimens of the same sulfur level, their corrosion fatigue crack growth rates were comparable in different orientations, which could be related to the exposure of fresh sulfides to the water environment. The percentages of sulfides per unit area, by quantitative metallography, were comparable for the steel specimens of both orientations. When the steel sulfur content was decreased to a critical sulfur content 0.005 wt.%, the crack growth rates decreased remarkably.

  20. Wear Resistance of H13 and a New Hot-Work Die Steel at High temperature

    NASA Astrophysics Data System (ADS)

    Li, Shuang; Wu, Xiaochun; Chen, Shihao; Li, Junwan

    2016-07-01

    The friction and wear behaviors of a new hot-work die steel, SDCM-SS, were studied at high temperature under dry air conditions. The wear mechanism and microstructural characteristics of the SDCM-SS steel were also investigated. The results showed that the SDCM-SS steel had greater wear resistance compared with H13 steel; this was owed to its high oxidizability and temper stability. These features facilitate the generation, growth, and maintenance of a tribo-oxide layer at high temperature under relatively stable conditions. The high oxidizability and thermal stability of the SDCM-SS steel originate from its particular alloy design. No chromium is added to the steel; this ensures that the material has high oxidizability, and facilitates the generation of tribo-oxides during the sliding process. Molybdenum, tungsten, and vanadium additions promote the high temper resistance and stability of the steel. Many fine Mo2C and VC carbides precipitate during the tempering of SDCM-SS steel. During sliding, these carbides can delay the recovery process and postpone martensitic softening. The high temper stability postpones the transition from mild to severe wear and ensures that conditions of mild oxidative wear are maintained. Mild oxidative wear is the dominant wear mechanism for SDCM-SS steel between 400 and 700 °C.

  1. Microstructural, Structural, and Thermal Characterization of Annealed Carbon Steels

    NASA Astrophysics Data System (ADS)

    Lara-Guevara, A.; Ortiz-Echeverri, C. J.; Rojas-Rodriguez, I.; Mosquera-Mosquera, J. C.; Ariza-Calderón, H.; Ayala-Garcia, I.; Rodriguez-García, M. E.

    2016-10-01

    As is well known, the metallurgical microstructure of carbon steel is formed by ferrite and pearlite after the annealing heat treatment. When the cooling rate increases, the diffusive process is interrupted causing a change in the metallurgical microstructure which will affect steel properties. The aim of this work was to study thermal, structural, and microstructural properties of annealed carbon steel samples with four different carbon contents. Crystalline structure and crystalline quality were studied by the X-ray diffraction technique, where the full width at half maximum analysis showed that as the carbon content increased, the crystalline quality decreased. The metallurgical microstructure morphology was studied by scanning electron microscopy. The thermal diffusivity and the heat capacity were determined by the photoacoustic technique and by the thermal relaxation method, respectively. The thermal diffusivity and the thermal conductivity decreased as the carbon content increased. The amplitude signal of photothermal radiometry increased as the carbon content increased, while the phase signal of photothermal radiometry did not show significant differences among studied carbon steel types. The photoacoustic technique represents an important alternative in the steel characterization field.

  2. Effect of Cr content on the corrosion performance of low-Cr alloy steel in a CO2 environment

    NASA Astrophysics Data System (ADS)

    Xu, Lining; Wang, Bei; Zhu, Jinyang; Li, Wei; Zheng, Ziyi

    2016-08-01

    Low-Cr alloy steel demonstrates lower corrosion rate than does C steel in a high-temperature and high-pressure CO2-containing environment. This study aimed to clarify the role of the Cr content in mitigating corrosion and reports the performance of 1%Cr, 2%Cr, 3%Cr, 4%Cr, 5%Cr, and 6.5%Cr steels. The results show that low-Cr alloy steel in CO2 at 80 °C and 0.8 MPa possesses spontaneous prepassivation characteristics when the Cr content is 3% or higher. Furthermore, the formation and peel-off of a prepassivation film on 3%Cr-6.5%Cr steels surfaces during polarization demonstrate that adequate amount of Cr in the steel substrate can cause protective layer. The main component of prepassivation film on 3%Cr steel is Cr(OH)3. Thus, the role of Cr is revealed. An adequate amount of Cr in the steel substrate causes the formation of protective Cr(OH)3 layer, which helps low-Cr steel to possess prepassivation characteristics. Prepassivation is the reason why low-Cr steel has a lower corrosion rate than C steel.

  3. Study of biocompatibility of medical grade high nitrogen nickel-free austenitic stainless steel in vitro.

    PubMed

    Li, Menghua; Yin, Tieying; Wang, Yazhou; Du, Feifei; Zou, Xingzheng; Gregersen, Hans; Wang, Guixue

    2014-10-01

    Adverse effects of nickel ions being released into the living organism have resulted in development of high nitrogen nickel-free austenitic stainless steels for medical applications. Nitrogen not only replaces nickel for austenitic structure stability but also improves steel properties. The cell cytocompatibility, blood compatibility and cell response of high nitrogen nickel-free austenitic stainless steel were studied in vitro. The mechanical properties and microstructure of this stainless steel were compared to the currently used 316L stainless steel. It was shown that the new steel material had comparable basic mechanical properties to 316L stainless steel and preserved the single austenite organization. The cell toxicity test showed no significant toxic side effects for MC3T3-E1 cells compared to nitinol alloy. Cell adhesion testing showed that the number of MC3T3-E1 cells was more than that on nitinol alloy and the cells grew in good condition. The hemolysis rate was lower than the national standard of 5% without influence on platelets. The total intracellular protein content and ALP activity and quantification of mineralization showed good cell response. We conclude that the high nitrogen nickel-free austenitic stainless steel is a promising new biomedical material for coronary stent development. PMID:25175259

  4. Study of biocompatibility of medical grade high nitrogen nickel-free austenitic stainless steel in vitro.

    PubMed

    Li, Menghua; Yin, Tieying; Wang, Yazhou; Du, Feifei; Zou, Xingzheng; Gregersen, Hans; Wang, Guixue

    2014-10-01

    Adverse effects of nickel ions being released into the living organism have resulted in development of high nitrogen nickel-free austenitic stainless steels for medical applications. Nitrogen not only replaces nickel for austenitic structure stability but also improves steel properties. The cell cytocompatibility, blood compatibility and cell response of high nitrogen nickel-free austenitic stainless steel were studied in vitro. The mechanical properties and microstructure of this stainless steel were compared to the currently used 316L stainless steel. It was shown that the new steel material had comparable basic mechanical properties to 316L stainless steel and preserved the single austenite organization. The cell toxicity test showed no significant toxic side effects for MC3T3-E1 cells compared to nitinol alloy. Cell adhesion testing showed that the number of MC3T3-E1 cells was more than that on nitinol alloy and the cells grew in good condition. The hemolysis rate was lower than the national standard of 5% without influence on platelets. The total intracellular protein content and ALP activity and quantification of mineralization showed good cell response. We conclude that the high nitrogen nickel-free austenitic stainless steel is a promising new biomedical material for coronary stent development.

  5. Review on Cold-Formed Steel Connections

    PubMed Central

    Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  6. Review on cold-formed steel connections.

    PubMed

    Lee, Yeong Huei; Tan, Cher Siang; Mohammad, Shahrin; Tahir, Mahmood Md; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed.

  7. Review on cold-formed steel connections.

    PubMed

    Lee, Yeong Huei; Tan, Cher Siang; Mohammad, Shahrin; Tahir, Mahmood Md; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  8. 7. BUILDING 604F, INTERIOR OF BULL PEN SHOWING TESTING STAND ...

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

    7. BUILDING 604-F, INTERIOR OF BULL PEN SHOWING TESTING STAND AND HEAVY WOOD LINING ON CONCRETE WALLS. STEEL PLATE ABOVE TEST STAND DEFLECTS SHRAPNEL, SCREEN FURTHER HELPS TO CONTAIN PARTICLES. ONLY SMALL EXPLOSIVES WERE TESTED HERE (GRENADES, MINES, BOMB FUZES, ETC.). - Picatinny Arsenal, 600 Area, Test Areas District, State Route 15 near I-80, Dover, Morris County, NJ

  9. Scientific American Frontiers Teaching Guides for Shows 901-905, October 1998-April 1999.

    ERIC Educational Resources Information Center

    Connecticut Public Television, Hartford.

    These teaching guides are intended to supplement the shows of the ninth season (1998-99) of the PBS Television Series "Scientific American Frontiers." Episode 901 is entitled "Science in Paradise: Another Side of the Caribbean." The teaching guide contains information and activities on hawksbill turtles, volcanic eruptions, playing the steel pan,…

  10. 38. Photocopy of photograph. STEEL PLANT, BOILERS UNDER CONSTRUCTION IN ...

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

    38. Photocopy of photograph. STEEL PLANT, BOILERS UNDER CONSTRUCTION IN BOILER PLANT LOCATED EAST OF MAIN STEEL PLANT, 1909. (From the Bethlehem Steel Corporation collection, Seattle, WA) - Irondale Iron & Steel Plant, Port Townsend, Jefferson County, WA

  11. Magnetic and Magnetostrictive Characterization and Modeling of High Strength Steel

    NASA Astrophysics Data System (ADS)

    Burgy, Christopher Donald

    High strength steels exhibit small amounts of magnetostriction, which is a useful property for non-destructive testing amongst other things. This property cannot currently be fully utilized due to a lack of adequate measurements and models. This thesis reports measurements of these material parameters, and derives a model using these parameters to predict magnetization changes due to the application of compressive stresses and magnetic fields. The resulting Preisach model, coupled with COMSOL MultiphysicsRTM finite element modeling, accurately predicts the magnetization change seen in a separate high strength steel sample previously measured by the National Institute of Standards and Technology. Three sets of measurements on low-carbon, low-alloy high strength steel are introduced in this research. The first experiment measured magnetostriction in steel rods under uniaxial compressive stresses and magnetic fields. The second experiment consisted of magnetostriction and magnetization measurements of the same steel rods under the influence of bi-axially applied magnetic fields. The final experiment quantified the small effect that temperature has on magnetization of steels. The experiments demonstrated that the widely used approximation of stress as an "effective field" is inadequate, and that temperatures between -50 and 100 °C cause minimal changes in magnetization. Preisach model parameters for the prediction of the magnetomechanical effect were derived from the experiments. The resulting model accurately predicts experimentally derived major and minor loops for a high strength steel sample, including the bulging and coincident points attributed to compressive stresses. A framework is presented which couples the uniaxial magnetomechanical model with a finite element package, and was used successfully to predict experimentally measured magnetization changes on a complex sample. These results show that a 1-D magnetomechanical model can be applied to predict 3-D

  12. 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.

  13. Fatigue crack growth at elevated temperature 316 stainless steel and H-13 steel

    NASA Technical Reports Server (NTRS)

    Chen, W. C.; Liu, H. W.

    1976-01-01

    Crack growths were measured at elevated temperatures under four types of loading: pp, pc, cp, and cc. In H-13 steel, all these four types of loading gave nearly the same crack growth rates, and the length of hold time had negligible effects. In AISI 316 stainless steel, the hold time effects on crack growth rate were negligible if the loading was tension-tension type; however, these effects were significant in reversed bending load, and the crack growth rates under these four types of loading varied considerably. Both tensile and compressive hold times caused increased crack growth rate, but the compressive hold period was more deleterious than the tensile one. Metallographic examination showed that all the crack paths under different types of loading were largely transgranular for both CTS tension-tension specimens and SEN reversed cantilever bending specimens. In addition, an electric potential technique was used to monitor crack growth at elevated temperature.

  14. Next Generation Nuclear Plant Reactor Pressure Vessel Materials Research and Development Plan (PLN-2803)

    SciTech Connect

    J. K. Wright; R. N. Wright

    2008-04-01

    The U.S. Department of Energy has selected the High Temperature Gas-cooled Reactor design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic, or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development Program is responsible for performing research and development on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. Studies of potential Reactor Pressure Vessel (RPV) steels have been carried out as part of the pre-conceptual design studies. These design studies generally focus on American Society of Mechanical Engineers (ASME) Code status of the steels, temperature limits, and allowable stresses. Three realistic candidate materials have been identified by this process: conventional light water reactor RPV steels A508/533, 2¼Cr-1Mo in the annealed condition, and modified 9Cr 1Mo ferritic martenistic steel. Based on superior strength and higher temperature limits, the modified 9Cr-1Mo steel has been identified by the majority of design engineers as the preferred choice for the RPV. All of the vendors have

  15. Influence of Manufacturing Processes and Microstructures on the Performance and Manufacturability of Advanced High Strength Steels

    SciTech Connect

    Choi, Kyoo Sil; Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.

    2009-10-01

    Advanced high strength steels (AHSS) are performance-based steel grades and their global material properties can be achieved with various steel chemistries and manufacturing processes, leading to various microstructures. In this paper, we investigate the influence of supplier variation and resulting microstructure difference on the overall mechanical properties as well as local formability behaviors of advanced high strength steels (AHSS). For this purpose, we first examined the basic material properties and the transformation kinetics of TRansformation Induced Plasticity (TRIP) 800 steels from three different suppliers under different testing temperatures. The experimental results show that there is a significant supplier (i.e., manufacturing process) dependency of the TRIP 800 steel mechanical and microstructure properties. Next, we examined the local formability of two commercial Dual Phase (DP) 980 steels during stamping process. The two commercial DP 980 steels also exhibit noticeably different formability during stamping process in the sense that one of them shows severe tendency for shear fracture. Microstructure-based finite element analyses are carried out next to simulate the localized deformation process with the two DP 980 microstructures, and the results suggest that the possible reason for the difference in formability lies in the morphology of the hard martensite phase in the DP microstructure.

  16. Influence of Direct Quenching on Microstructure and Mechanical Properties of Steel Plate for Large Oil Storage Tanks

    NASA Astrophysics Data System (ADS)

    Xiao, Guizhi; di, Hongshuang; Zhu, Fuxian; Chen, Bingzhang; Qiu, Bing

    2010-08-01

    The influence of direct quenching on microstructure and mechanical properties of high performance steel plates for large oil storage tanks was studied. The direct quenched and tempered (DQ&T) steel plates were rolled at different finish rolling temperatures (1113 and 1173 K), and their microstructures and mechanical properties were compared with those of reheat quenched and tempered (RQ&T) steel plate. The optical microscopy of the DQ steel shows deformed grains elongated along the rolling direction, while complete equiaxed grains are visible in RQ steel. Transmission electron microscopy (TEM) of the DQ steel shows refined lath martensite with high density of dislocations, which acts as preferred precipitation sites for NbC or Nb(C,N) particles during tempering. In all the plates, strength decreases with increasing tempering temperature. The strength of RQ steel increased significantly compared with that of DQ steel at the higher tempering temperature, which leads to better tempering resistance in DQ steels. The optimum combination of strength and toughness (yield strength (YS) reaches 585 MPa, tensile strength (TS) 667 MPa, and Charpy impact energy at 253 K of 291 J) in the DQ steels is achieved by quenching at 1113 K and tempering at 923 K.

  17. 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.

  18. Electrochemically induced annealing of stainless-steel surfaces

    NASA Astrophysics Data System (ADS)

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

    2000-10-01

    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.

  19. Laser ignition of bulk 1018 carbon steel in pure oxygen

    NASA Technical Reports Server (NTRS)

    Nguyen, K.; Branch, M. C.

    1986-01-01

    Experiments were undertaken to study the ignition characteristics of bulk 1018 carbon steel in a pure oxygen environment. Cylindrical 1018 carbon steel specimens 5 mm in diameter and 5 mm high were ignited by a focused CW CO2 laser beam in a cool, static, pure oxygen environment at oxygen pressures ranging from 0.103 to 6.895 MPa. A two-color pyrometer was designed and used to measure the ignition temperatures of the specimens. The temperature history of a spot approximately 0.5 mm in diameter located at the center of the specimen top surface was recorded with a maximum time resolution of 25 microsec, and with an accuracy of a few percent. Ignition temperature of bulk 1018 carbon steel was identified from the temperature history curve with the aid of the light intensity curve. Results show that 1018 carbon steel specimens ignite at temperatures between 1388 and 1450 K, which are below the melting range of the alloy (1662-1685 K). The ignition temperature of 1018 carbon steel is mildly dependent on oxygen pressure over the range of oxygen pressure investigated in this study.

  20. Ni-Flash-Coated Galvannealed Steel Sheet with Improved Properties

    NASA Astrophysics Data System (ADS)

    Pradhan, D.; Dutta, M.; Venugopalan, T.

    2016-09-01

    In the last several years, automobile industries have increasingly focused on galvannealed (GA) steel sheet due to their superior properties such as weldability, paintability and corrosion protection. To improve the properties further, different coatings on GA have been reported. In this context, an electroplating process (flash coating) of bright and adherent Ni plating was developed on GA steel sheet for covering the GA defects and enhancing the performances such as weldability, frictional behavior, corrosion resistance and phosphatability. For better illustration, a comparative study with bare GA steel sheet has also been carried out. The maximum electroplating current density of 700 A/m2 yielded higher cathode current efficiency of 95-98%. The performances showed that Ni-coated (coating time 5-7 s) GA steel sheet has better spot weldability, lower dynamic coefficient of friction (0.07 in lubrication) and three times more corrosion resistance compared to bare GA steel sheet. Plate-like crystal of phosphate coating with size of 10-25 µm was obtained on the Ni-coated GA. The main phase in the phosphate compound was identified as hopeite (63.4 wt.%) along with other phases such as spencerite (28.3 wt.%) and phosphophyllite (8.3 wt.%).

  1. Steel catenary risers for semisubmersible based floating production systems

    SciTech Connect

    Hays, P.R.

    1996-12-31

    The DeepStar production riser committee has investigated the feasibility of using steel catenary risers (SCRs) in water depths of 3,000--6,000 ft. Using Sonat`s George Richardson as the base semisubmersible, DeepStar has examined both extreme event response and fatigue life of an SCR made of pipe sections welded end-to-end. Concepts using alternative materials were investigated. This included steel, steel with titanium and titanium catenary risers. The pros and cons of frequency domain versus time domain analysis were investigated with a commercially available analysis package. A second study outlined a definitive analysis procedure which optimized the analysis time requirements. Analyses showed that steel catenary risers are feasible for semisubmersible based floating production systems. For the DeepStar Gulf of Mexico design criteria, alternative materials are not required. The greatest fatigue damage occurs in the touchdown region of the riser. Mild sea states contribute most to fatigue damage near riser touchdown. Wave drift and wind forces provide a significant contribution to touchdown area fatigue damage. Estimated fatigue lives are unacceptable. Although the rotations of the upper end of the riser are large relative to an SCR attached to a TLP, the rotation required can probably be accommodated with existing technology. For the case of product export, steel catenary risers provide very cost effective and readily installable deep water riser alternatives.

  2. 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.

  3. Steel erected at A-3 Test Stand

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Workers erect the first fabricated steel girders to arrive at the A-3 Test Stand at Stennis Space Center. Steel work began at the construction site Oct. 29 and is scheduled to continue into next spring.

  4. Corrosion control of steel-reinforced concrete

    NASA Astrophysics Data System (ADS)

    Chung, D. D. L.

    2000-10-01

    The methods and materials for corrosion control of steel-reinforced concrete are reviewed. The methods are steel surface treatment, the use of admixtures in concrete, surface coating on concrete, and cathodic protection.

  5. 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.

  6. Corrosion monitoring of reinforcing steel in concrete by electrochemical sensors

    NASA Astrophysics Data System (ADS)

    Qiao, Guofu; Hong, Yi; Ou, Jinping

    2010-04-01

    Health degradation by corrosion of steel in civil engineering, especially in rough environment, is a persistent problem. Structural health monitoring (SHM) techniques can lead to improved estimates of structural safety and serviceability. A novel all solid state-current confined corrosion sensor has been developed to provide the platform for corrosion monitoring of the steel bar in concrete beam by electrochemical method. Finite element method has been used to certify the current confined effect of the sensor. The sensors have been used in concrete beams to monitor the corrosion of the steel bar. Also, half-cell potential of the beam has obtained. The results shows that the corrosion sensor can effectively confine the current in the fixed area which is 45mm×π×Dsteel bar and the monitoring results of the corrosion sensor are accurate.

  7. Corrosion behavior of carbon steels under tuff repository environmental conditions

    SciTech Connect

    McCright, R.D.; Weiss, H.

    1984-10-01

    Carbon steels may be used for borehole liners in a potential high-level nuclear waste repository in tuff in Nevada. Borehole liners are needed to facilitate emplacement of the waste packages and to facilitate retrieval of the packages, if required. Corrosion rates of low carbon structural steels AISI 1020 and ASTM A-36 were determined in J-13 well water and in saturated steam at 100{sup 0}C. Tests were conducted in air-sparged J-13 water to attain more oxidizing conditions representative of irradiated aqueous environments. A limited number of irradiation corrosion and stress corrosion tests were performed. Chromium-molybdenum alloy steels and cast irons were also tested. These materials showed lower general corrosion but were susceptible to stress corrosion cracking when welded. 4 references, 4 tables.

  8. 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.

  9. Serrated flow behavior in AL6XN austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Meng, L. J.; Sun, J.; Xing, H.; Pang, G. W.

    2009-10-01

    Serrated flow behavior of the AL6XN austenitic stainless steel has been investigated at different temperatures and strain rates. The results show the serrated flow, peak/plateau in flow stress and negative strain rate sensitivity appearing in tensile deformation of the AL6XN steel at 773-973 K and 3.3 × 10 -5-3.3 × 10 -3 s -1 (excluding 873 K, 3.3 × 10 -5 s -1), suggesting the occurrence of dynamic strain aging (DSA). The activation energy for type-A and -(A + B) serrations was calculated to be 304 kJ/mol and diffusion of substitutional solutes, such as chromium and molybdenum is considered as the mechanism of serrated flow. TEM observations further revealed a typical planar slip mode in the regime of DSA of the deformed AL6XN steel.

  10. ESF GROUND SUPPORT - STRUCTURAL STEEL ANALYSIS

    SciTech Connect

    T. Misiak

    1996-06-26

    The purpose and objective of this analysis are to expand the level of detail and confirm member sizes for steel sets included in the Ground Support Design Analysis, Reference 5.20. This analysis also provides bounding values and details and defines critical design attributes for alternative configurations of the steel set. One possible configuration for the steel set is presented. This analysis covers the steel set design for the Exploratory Studies Facility (ESF) entire Main Loop 25-foot diameter tunnel.

  11. Experimental and analytical behavior of strengthened reinforced concrete columns with steel angles and strips

    NASA Astrophysics Data System (ADS)

    Khalifa, Essam S.; Al-Tersawy, Sherif H.

    2014-06-01

    of steel elements. This adopted model is simplified and applicable to practical design field. In this respect, the experimental results and those of the analytical model showed a good agreement.

  12. Effect of Different Casting Parameters on the Cleanliness of High Manganese Steel Ingots Compared to High Carbon Steel

    NASA Astrophysics Data System (ADS)

    von Schweinichen, Petrico; Chen, Zhiye; Senk, Dieter; Lob, Alexander

    2013-12-01

    The increasing demand for excellent steel properties has led to the creation of new steel grades such as high manganese TWIP and TRIP steels which are scientifically examined in Germany within the international research framework of the SFB 761 "Steel-ab initio." The production of these high-technology products, utilizing mainly the ingot-casting method, leads to new challenges in the prevention of cast defects. At RWTH Aachen University, a systematic investigation of the solidification process as it relates to shrinkage cavity, macrosegregation, cleanliness, and surface imperfections in as-cast ingots is being conducted. A particular attention was devoted to the effects of such casting parameters as superheat, pouring rate, hot top, and stirring conditions on the solidification and cleanliness of low carbon alloyed and high manganese alloyed steels. The experimental results show that rising manganese content leads to a higher amount and larger size of inclusions while rising carbon content enhances the inclusion generation in the same way. It was found that a bottom teeming system combined with an inert gas atmosphere produces the best quality and that if casting is performed with a runner-system, it is important to use a SiO2-free refractory to avoid oxidizing the Mn content of the melt to MnO inclusions by redox-reactions.

  13. Steel erected at A-3 Test Stand

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Fabricated steel began arriving by truck Oct. 24 for construction of the A-3 Test Stand that will be used to test the engine for the nation's next generation of moon rockets. Within days workers from Lafayette Steel Erector Inc. began assembling the 16 steel stages needed on the foundation and footings poured in the previous year.

  14. Steeling and Resilience in Art Education

    ERIC Educational Resources Information Center

    Heise, Donalyn

    2014-01-01

    Steel is an incredibly strong alloy of iron and carbon. Due to its incredible strength and durability, this resilient material is commonly used for constructing buildings. The transitive verb "steeling" is defined in Miriam-Webster dictionary as "to fill with resolution or determination, as in, she 'steeled herself to face the…

  15. Metallography of maraging 350 steel

    SciTech Connect

    Hutson, S.M.; Merten, C.W.

    1987-01-01

    A technique for etching maraging 350 steel with Glyceregia is described. Surface activation procedures are integral to this technique. Microstructural features revealed by this technique are compared with those obtained with Kalling's reagent, Fry's reagent, and 5% Nital, three etchants commonly used to reveal microstructures of maraging steels. Features which may be simultaneously revealed using Glyceregia include prior austenite grain boundaries, martensitic structure, precipitates, titanium carbo-nitrides, and reverted austenite. The other etchants examined in this investigation typically reveal only a few of the microstructural features detailed above at any one time. 11 refs., 10 figs., 2 tabs.

  16. Teaching Steel Connections Using an Interactive Virtual Steel Sculpture

    ERIC Educational Resources Information Center

    Moaveni, Saeed; Chou, Karen C.

    2015-01-01

    Steel connections play important roles in the integrity of a structure, and many structural failures are attributed to connection failures. Connections are the glue that holds a structure together. The failures of the Hartford Coliseum in 1977, the Hyatt Regency Hotel in Kansas City in 1980, and the I-35W Bridge in Minneapolis in 2007 are all…

  17. Identification of Defect Prone Peritectic Steel Grades by Analyzing High-Temperature Phase Transformations

    NASA Astrophysics Data System (ADS)

    Presoly, Peter; Pierer, Robert; Bernhard, Christian

    2013-12-01

    Continuous casting of peritectic steels is often difficult and critical; bad surface quality, cracks, and even breakouts may occur. The initial solidification of peritectic steels within the mold leads to formation of surface depressions and uneven shell growth. As commercial steels are always multicomponent alloys, the influence also of the alloying elements besides carbon on the peritectic phase transition needs to be taken into account. Information on the solidification sequence and phase diagrams for initial solidification are lacking especially for new steel grades, like high-alloyed TRIP-steels with high Mn, Si, and particularly high Al contents. Based on a comprehensive method development, the current study shows that differential scanning calorimeter measurements allow a clear prediction if an alloy is peritectic ( i.e., critical to cast). In order to confirm these results, thermo-optical analyses with a high-temperature laser-scanning-confocal-microscope are performed to observe the phase transformations in situ up to the melting point.

  18. HYDROGEN EFFECTS ON THE FRACTURE TOUGHNESS PROPERTIES OF FORGED STAINLESS STEELS

    SciTech Connect

    Morgan, M

    2008-03-28

    The effect of hydrogen on the fracture toughness properties of Types 304L, 316L and 21-6-9 forged stainless steels was investigated. Fracture toughness samples were fabricated from forward-extruded forgings. Samples were uniformly saturated with hydrogen after exposure to hydrogen gas at 34 MPa or 69 and 623 K prior to testing. The fracture toughness properties were characterized by measuring the J-R behavior at ambient temperature in air. The results show that the hydrogen-charged steels have fracture toughness values that were about 50-60% of the values measured for the unexposed steels. The reduction in fracture toughness was accompanied by a change in fracture appearance. Both uncharged and hydrogen-charged samples failed by microvoid nucleation and coalescence, but the fracture surfaces of the hydrogen-charged steels had smaller microvoids. Type 316L stainless steel had the highest fracture toughness properties and the greatest resistance to hydrogen degradation.

  19. Microstructure and Corrosion Behavior of Hot-Deformed and Cold-Strained High-Mn Steels

    NASA Astrophysics Data System (ADS)

    Grajcar, A.; Kciuk, M.; Topolska, S.; Płachcińska, A.

    2016-06-01

    The electrochemical corrosion properties of 26Mn-3Si-3Al and 27Mn-4Si-2Al austenitic steels in two different states were studied in 0.1 M H2SO4 and 3.5% NaCl using potentiodynamic polarization tests. The effect of cold deformation on the microstructure and corrosion behavior of steels was analyzed. In acid solution, both steels exhibited lower corrosion resistance than in chloride solution independently on the steel state (hot-rolled, cold-worked). Cold deformation decreases the corrosion resistance, though this effect is smaller than the effect of chemical composition related to the combined Al + Si addition. All steels showed the evidence of pitting corrosion. The intensive dissolution of Fe and Mn takes place in the acid medium.

  20. Current status and future R&D for reduced-activation ferritic/martensitic steels

    NASA Astrophysics Data System (ADS)

    Hishinuma, A.; Kohyama, A.; Klueh, R. L.; Gelles, D. S.; Dietz, W.; Ehrlich, K.

    1998-10-01

    International research and development programs on reduced-activation ferritic/martensitic steels, the primary candidate-alloys for a DEMO fusion reactor and beyond, are briefly summarized, along with some information on conventional steels. An International Energy Agency (IEA) collaborative test program to determine the feasibility of reduced-activation ferritic/martensitic steels for fusion is in progress and will be completed within this century. Baseline properties including typical irradiation behavior for Fe-(7-9)%Cr reduced-activation ferritic steels are shown. Most of the data are for a heat of modified F82H steel, purchased for the IEA program. Experimental plans to explore possible problems and solutions for fusion devices using ferromagnetic materials are introduced. The preliminary results show that it should be possible to use a ferromagnetic vacuum vessel in tokamak devices.

  1. 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.

  2. Mössbauer study on the deformed surface of high-manganese steel

    NASA Astrophysics Data System (ADS)

    Nasu, S.; Tanimoto, H.; Fujita, F. E.

    1990-07-01

    Conversion electron, X-ray backscattering and conventional transmission57Fe Mössbauer measurements have been performed to investigate the origin of the remarkable work hardening at the surface of a high-manganese steel which is called Hadfield steel. Mössbauer results show that α' martensite has no relation to work hardening. From the comparison of conversion electron to X-ray backscattering spectra, the occurrence of decarbonization is suggested at the surface. The transmission Mössbauer spectrum at 20 K for deformed specimen shows the existence of ɛ martensite which could be related to the work hardening of Hadfield steel.

  3. Influence of Martensite Mechanical Properties on Failure Mode and Ductility of Dual Phase Steels

    SciTech Connect

    Choi, Kyoo Sil; Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.

    2009-04-01

    In this paper, the effects of the mechanical properties of the martensite phase on the failure mode and ductility of dual phase (DP) steels are investigated using a micromechanics-based finite element method. Actual microstructures of DP sheet steels obtained from scanning electron microscopy are used as representative volume element (RVE) in two-dimensional plane-stress finite element calculations. Failure is predicted as plastic strain localization in the RVE during deformation. The mechanical properties of the ferrite and martensite phases in a commercial DP 980 steel are obtained based on the in-situ X-ray diffraction measurements of a uniaxial tensile test. Computations are then conducted on the RVE in order to investigate the influence of the martensite mechanical properties and volume fraction on the macroscopic behavior and failure mode of DP steels. The computations show that, as the strength and volume fraction of the martensite phase increase, the ultimate tensile strength (UTS) of DP steels increases but the UTS strain and failure strain decrease. These results agree well with the general experimental observations on DP steels. Additionally, shear dominant failure modes usually develop for DP steels with lower martensite strengths, whereas split failure modes typically develop for DP steels with higher martensite strengths.

  4. Residual stress measurements in forced convective quenched steel bars by means of neutron diffraction

    SciTech Connect

    Hernandez-Morales, B.; Hawbolt, B.E.; Brimacombe, J.K.

    1996-12-31

    The residual stress distributions in 38.1 mm-dia., forced convective quenched bars of interstitial-free (IF), 1045 carbon, and alloyed steels were determined by neutron diffraction. The IF and 1045 carbon steel quenched bars exhibited compressive axial and circumferential (hoop) residual stresses near the surface and tensile values at the center. The radial residual stresses were tensile at all radial positions, decreasing towards zero near the surface. In contrast, the measured axial and circumferential components of the residual stress tensor in the alloyed eutectoid steel quenched bar were tensile near the surface and decreased to compressive values at the center. The radial component showed a maximum compressive value at the center and approached zero close to the surface. Metallographic analysis and hardness testing of the three steel specimens, revealed that the IF steel had transformed completely to ferrite, while the 1045 carbon steel bar transformed to martensite near the surface and a mixture of pearlite, ferrite and martensite at the center. On the other hand, the alloyed eutectoid steel specimen transformed entirely to martensite with small amounts of bainite near the center of the rod. The observed differences in the residual stress distributions in the three steels were explained based on the sequence of phase transformations that took place during quenching.

  5. Fe-Zn Alloy Coating on Galvannealed (GA) Steel Sheet to Improve Product Qualities

    NASA Astrophysics Data System (ADS)

    Pradhan, Debabrata; Guin, Akshya Kumar; Raju, Pankaj; Manna, Manindra; Dutta, Monojit; Venugopalan, T.

    2014-09-01

    Galvannealed steel sheets (GA) have become the mainstream steel sheet for automobile applications because of their superior corrosion resistance, paintability, and weldability. To impart specific properties, different coatings on GA steel sheet were reported to improve properties further. In this context, we have developed an electroplating process (flash coating) for bright and adherent Fe-Zn alloy coating on GA steel sheet to enhance performances such as weldability, frictional behavior, phosphatability, and defect coverage. A comparative study with bare GA steel sheet was carried out for better elastration. The electroplating time was reduced below 10 s for practical applicability in an industrial coating line by modulating the bath composition. Electroplating was performed at current density of 200-500 A/m2 which yielded with higher cathode current efficiency of 85-95%. The performance results show that Fe-10 wt.% Zn-coated GA steel sheet (coating time 7 s) has better spot weldability, lower dynamic coefficient of friction (0.06-0.07 in lubrication), and better corrosion resistance compared to bare GA steel sheet. Uniform phosphate coating with globular crystal size of 2-5 µm was obtained on Fe-Zn flash-coated GA steel sheet. Hopeite was the main phosphate compound (77.9 wt.%) identified along with spencerite (13.6 wt.%) and phosphophyllite (8.5 wt.%).

  6. Requirements for a cleanable steel HEPA filter derived from a systems analysis

    SciTech Connect

    Bergman, W.

    1996-06-01

    A systems analysis was conducted to determine customer requirements for a cleanable high efficiency particulate air (HEPA) filter in DOE Environmental Management (EM) facilities. The three principal drivers for cleanable steel HEPA are large cost savings, improved filter reliability, and new regulations; they produce a strong incentive to DOE customers to use cleanable steel HEPA filters. Input for customer requirements were obtained from field trips to EM sites and from discussions. Most existing applications require that cleanable steel HEPA filters meet size/performance requirements of standard glass HEPA filters; applications in new facilities can relax size/weight/pressure drop requirements on a case-by-case basis. We then obtained input from commercial firms on availability of cleanable steel HEPA filters. Systems analysis then showed that currently available technology was only able to meet customer needs in a limited number of cases. Further development is needed to meet requirements of EM customers. For cleanable steel HEPA to be retrofitted into existing systems, pressure drop and weight must be reduced. Pressure drop can be reduced by developing steel fiber media from 0.5 {mu}m dia steel fibers. Weight can be reduced by packaging the steel fiber media in one of the standard HEPA configurations. Although most applications will be able to use standard 304 or 316L alloys, an acid resistant alloy such as Hastelloy or Inconel will be needed for incinerator and other thermal processes.

  7. Development of nano-structured duplex and ferritic stainless steels by pulverisette planetary milling followed by pressureless sintering

    SciTech Connect

    R, Shashanka Chaira, D.

    2015-01-15

    Nano-structured duplex and ferritic stainless steel powders are prepared by planetary milling of elemental Fe, Cr and Ni powder for 40 h and then consolidated by conventional pressureless sintering. The progress of milling and the continuous refinement of stainless steel powders have been confirmed by means of X-ray diffraction and scanning electron microscopy. Activation energy for the formation of duplex and ferritic stainless steels is calculated by Kissinger method using differential scanning calorimetry and is found to be 159.24 and 90.17 KJ/mol respectively. Both duplex and ferritic stainless steel powders are consolidated at 1000, 1200 and 1400 °C in argon atmosphere to study microstructure, density and hardness. Maximum sintered density of 90% and Vickers microhardness of 550 HV are achieved for duplex stainless steel sintered at 1400 °C for 1 h. Similarly, 92% sintered density and 263 HV microhardness are achieved for ferritic stainless steel sintered at 1400 °C. - Highlights: • Synthesized duplex and ferritic stainless steels by pulverisette planetary milling • Calculated activation energy for the formation of duplex and ferritic stainless steels • Studied the effect of sintering temperature on density, hardness and microstructure • Duplex stainless steel exhibits 90% sintered density and microhardness of 550 HV. • Ferritic stainless steel shows 92% sintered density and 263 HV microhardness.

  8. Oxidation behavior of ferritic/martensitic steels in stagnant liquid LBE saturated by oxygen at 600 °C

    NASA Astrophysics Data System (ADS)

    Shi, Quanqiang; Liu, Jian; Luan, He; Yang, Zhenguo; Wang, Wei; Yan, Wei; Shan, Yiyin; Yang, Ke

    2015-02-01

    Ferritic/martensitic (F/M) steels are primary candidates for application as cladding and structural materials in the Generation IV Nuclear Reactor, especially accelerator driven sub-critical system (ADS). The compatibility of F/M steels with liquid lead-bismuth eutectic (LBE) is a critical issue for development of ADS using liquid LBE as the coolant. In this work, the corrosion tests of two F/M steels, including a novel 9-12 Cr modified F/M steel named SIMP steel and a commercial T91 steel, were conducted in the static oxygen-saturated liquid LBE at 600 °C up to 1000 h, the microstructure of the oxide scale formed on these two steels was analyzed, the relationship between the microstructure and the oxidation behavior was studied, and the reason why the SIMP steel showed better oxidation resistance compared to T91 steel was analyzed. The results of this study confirmed that the oxidation behavior of the F/M steels in liquid metals is influenced by their alloying elements and microstructures.

  9. Effect of substrates on microstructure and mechanical properties of nano-eutectic 1080 steel produced by aluminothermic reaction

    SciTech Connect

    La, Peiqing Li, Zhengning; Li, Cuiling; Hu, Sulei; Lu, Xuefeng; Wei, Yupeng; Wei, Fuan

    2014-06-01

    Nano-eutectic bulk 1080 carbon steel was prepared on glass and copper substrates by an aluminothermic reaction casting. The microstructure of the steel was analyzed by an optical microscope, transmission electron microscopy, an electron probe micro-analyzer, a scanning electron microscope and X-ray diffraction. Results show that the microstructure of the steel consisted of a little cementite and lamellar eutectic pearlite. Average lamellar spacing of the pearlite prepared on copper and glass substrates was about 230 nm and 219 nm, respectively. Volume fraction of the pearlite of the two steels was about 95%. Hardness of the steel was about 229 and 270 HV. Tensile strength was about 610 and 641 MPa and tensile elongation was about 15% and 8%. Compressive strength was about 1043 and 1144 MPa. Compared with the steel prepared on copper substrate, the steel prepared on glass substrate had smaller lamellar spacing of the pearlite phase and higher strength, and low ductility due to the smaller spacing. - Highlights: • 1080-carbon steels were successfully prepared by an aluminothermic reaction casting. • Lamellar spacing of the nanoeutetic pearlite is less than 250 nm. • The compressive strength of the steel is about 1144 MPa. • The tensile ductility of the steel is about 15%.

  10. 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.

  11. The Role of Steel in the US Economy: Decomposing the 1982-1997 Forward and Backward Linkages of the Steel Industry

    SciTech Connect

    Anderson, Dave M.; Roop, Joseph M.

    2003-07-31

    This paper queries the benchmark input-output tables of the United States for 1982, 1987, 1992, and 1997 to examine both the industries that provide goods and services to the steel industry and the destination of steel products to other industries and final goods. This study provides a sense of how the industry changed over the 1982-1997 period and will aid in evaluation of new technology adoption by linking steel products to final consumers. Input-output analysis incorporates the ideas of interdependency, feedbacks, and general equilibrium into a single format. The Bureau of Economic Analysis (BEA) of the Department of Commerce prepares the official input-output tables for the United States every five years. The most recent table currently available is the 1997 table, released in 2002. It provides a snapshot of all transactions in 1997 at a given point in time, including sales of products to each industry (intermediate demand) as well as sales of products to final users (final demand). Fully disaggregated, the US input-output table specifies nearly 500 industries, and shows the distributions of inputs purchased from each and outputs sold to each. This makes a robust database for viewing detailed snapshots of the forward and backward linkages affecting the steel industry. The steel industry is one of the major producers of raw materials for industry and construction. Value of shipments in 2000 for the steel industry totaled over $70 billion. This paper highlights the interdependency of the various steel-using industries of the economy. It shows the downstream use by industry of steel as a commodity. It shows the response in the use of steel to industry-specific shocks to national final demand. It also documents the steel intensity of other industry sectors in the economy. The paper builds on the benchmark input-output tables to develop economic impact models. These models permit the examination of impacts on industrial output, employment, income, and other measures

  12. Development of Al-killed/Ti stabilized steels

    NASA Astrophysics Data System (ADS)

    Ramirez-Ledesma, A. L.; Aguilar-Mendez, M. A.; Rodriguez-Diaz, R. A.; >G Aramburo,

    2015-01-01

    Several Al-killed/Ti-stabilized low carbon steels were developed in a Mexican steel industry with the aim of obtaining an interstitial free steel for automotive applications. The steelmaking route involved the use of 100% sponge iron which was feed into an electric arc furnace, vacuum degassed, ladle treated and continuously casted. The resulting slabs were then hot rolled at 1100 °C and coiled at 650 °C. Then, the steel plates were cold rolled at room temperature and sheets annealed at 700 °C. As-cast micro structure showed the presence of α-ferrite with titanium nitrides in matrix and grain boundaries while in the ashot rolled condition, elongated grains showed the presence of titanium nitrides, titanium sulfides and titanium carbosulfides. The annealed sheets showed, additionally to the other precipitates, the presence of titanium carbides. Microstructure, texture, the Lankford ratio and mechanical properties of fully recrystallized coils fulfilled the target properties established by the automobile industry.

  13. Relationship between Material Properties and Local Formability of DP980 Steels

    SciTech Connect

    Choi, Kyoo Sil; Soulami, Ayoub; Li, Dongsheng; Sun, Xin; Khaleel, Mohammad A.; Xu, Le; Barlat, Frederic

    2012-04-24

    A noticeable degree of inconsistent forming behaviors has been observed for the 1st generation advanced high strength steels (AHSS) in production, and they appear to be associated with the inherent microstructural-level inhomogeneities for various AHSS. This indicates that the basic material property requirements and screening methods currently used for the mild steels and high strength low alloys (HSLA) are no longer sufficient for qualifying today’s AHSS. In order to establish more relevant material acceptance criteria for AHSS, the fundamental understandings on key mechanical properties and microstructural features influencing the local formability of AHSS need to be developed. For this purpose, in this study, DP980 was selected as model steels and eight different types of DP980 sheet steels were acquired from various steel suppliers. Various experiments were then performed on the eight different DP980 steels such as chemical composition analysis, static tensile test, hole expansion test, channel forming test. Scanning electron microscope (SEM) pictures of the DP980 steels were also obtained, and image processing tools were then adopted to those SEM pictures in order to quantify their various microstructural features. The results show that all DP980 steels show large discrepancy in their performance and that the tensile properties and hole expansion properties of these steels do not correlate with their local formability. According to the results up to date, it is not possible to correlate the microstructural features alone to the macroscopically measured deformation behaviors. In addition to image analysis, other experiments (i.e., nano-indentation test) are also planned to quantify the individual phase properties of the various DP steels.

  14. 73. Neg. No. F110K, Apr 24, 1931, INTERIORPRESSED STEEL BUILDING, ...

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

    73. Neg. No. F-110K, Apr 24, 1931, INTERIOR-PRESSED STEEL BUILDING, NORTHEAST END FACING NORTH, SHOWING FENDER PAINTING - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  15. Preformed posterior stainless steel crowns: an update.

    PubMed

    Croll, T P

    1999-02-01

    For almost 50 years, dentists have used stainless steel crowns for primary and permanent posterior teeth. No other type of restoration offers the convenience, low cost, durability, and reliability of such crowns when interim full-coronal coverage is required. Preformed stainless steel crowns have improved over the years. Better luting cements have been developed and different methods of crown manipulation have evolved. This article reviews stainless steel crown procedures for primary and permanent posterior teeth. Step-by-step placement of a primary molar stainless steel crown is documented and permanent molar stainless steel crown restoration is described. A method for repairing a worn-through crown also is reviewed.

  16. Advanced sheet steels for automotive applications

    NASA Astrophysics Data System (ADS)

    Fekete, James R.; Strugala, Donald C.; Yao, Zhicong

    1992-01-01

    Vacuum degassing has recently been used by sheet steel producers to improve their products' ductility and strength. Carbon contents can be reduced by an order of magnitude to less than 0.0030 wt.%. Through careful alloying and processing, a range of new steel products has been developed for the automotive industry. These products include interstitial-free, deep-drawing-quality steels; formable, high-strength, interstitial-free steels; and bake-hardenable steels. This article summarizes the chemistry and processing needed to produce these products.

  17. Imaging molten steel flow profiles

    NASA Astrophysics Data System (ADS)

    Binns, R.; Lyons, A. R. A.; Peyton, A. J.; Pritchard, W. D. N.

    2001-08-01

    Control of delivery of molten steel in continuous casting is critical in order to ensure stability of the meniscus and satisfactory mould flow patterns, which in turn are determinants of cleanness and surface quality of steel. Considerable effort has been expended over the last ten years on optimizing the design of the metal delivery system, particularly the pouring nozzle, in order to allow the consistent production of high quality steel at a high throughput. This paper looks forward to possible systems that are capable of tomographically imaging the distribution of molten steel flows in these applications. The paper will concentrate on the feasibility of using electromagnetic methods. The paper will present some initial results; an overview of the applied image reconstruction process will also be included. The paper will conclude with a discussion of possible future developments, such as the use of a tomographic or multi-frequency approach, future research on the reconstruction image procedures and the potential for visualization and flow measurement. There is a need for further research in this area and some priority areas for future work will be suggested.

  18. Precision machining of steel decahedrons

    NASA Technical Reports Server (NTRS)

    Abernathy, W. J.; Sealy, J. R.

    1972-01-01

    Production of highly accurate decahedron prisms from hardened stainless steel is discussed. Prism is used to check angular alignment of mounting pads of strapdown inertial guidance system. Accuracies obtainable using recommended process and details of operation are described. Photographic illustration of production device is included.

  19. 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.

  20. The effect of metal microstructure on the initial attachment of Escherichia coli to 1010 carbon steel.

    PubMed

    Javed, M A; Stoddart, P R; McArthur, S L; Wade, S A

    2013-09-01

    Metallurgical features have been shown to play an important role in the attachment of microorganisms to metal surfaces. In the present study, the influence of the microstructure of as-received (AR) and heat-treated (HT) 1010 carbon steel on the initial attachment of bacteria was investigated. Heat treatment was carried out with the aim of increasing the grain size of the carbon steel coupons. Mirror-polished carbon steel coupons were immersed in a minimal medium inoculated with Escherichia coli (ATCC 25922) to investigate the early (15, 30 and 60 min) and relatively longer-term (4 h) stages of bacterial attachment. The results showed preferential colonisation of bacteria on the grain boundaries of the steel coupons. The bacterial attachment to AR steel coupons was relatively uniform compared to the HT steel coupons where an increased number of localised aggregates of bacteria were found. Quantitative analysis showed that the ratio of the total number of isolated (i.e., single) bacteria to the number of bacteria in aggregates was significantly higher on the AR coupons than the HT coupons. Longer-term immersion studies showed production of extracellular polymeric substances by the bacteria and corrosion at the grain boundaries on both types of steel coupon tested.

  1. 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.

  2. Tool Steel Heat Treatment Optimization Using Neural Network Modeling

    NASA Astrophysics Data System (ADS)

    Podgornik, Bojan; Belič, Igor; Leskovšek, Vojteh; Godec, Matjaz

    2016-08-01

    Optimization of tool steel properties and corresponding heat treatment is mainly based on trial and error approach, which requires tremendous experimental work and resources. Therefore, there is a huge need for tools allowing prediction of mechanical properties of tool steels as a function of composition and heat treatment process variables. The aim of the present work was to explore the potential and possibilities of artificial neural network-based modeling to select and optimize vacuum heat treatment conditions depending on the hot work tool steel composition and required properties. In the current case training of the feedforward neural network with error backpropagation training scheme and four layers of neurons (8-20-20-2) scheme was based on the experimentally obtained tempering diagrams for ten different hot work tool steel compositions and at least two austenitizing temperatures. Results show that this type of modeling can be successfully used for detailed and multifunctional analysis of different influential parameters as well as to optimize heat treatment process of hot work tool steels depending on the composition. In terms of composition, V was found as the most beneficial alloying element increasing hardness and fracture toughness of hot work tool steel; Si, Mn, and Cr increase hardness but lead to reduced fracture toughness, while Mo has the opposite effect. Optimum concentration providing high KIc/HRC ratios would include 0.75 pct Si, 0.4 pct Mn, 5.1 pct Cr, 1.5 pct Mo, and 0.5 pct V, with the optimum heat treatment performed at lower austenitizing and intermediate tempering temperatures.

  3. Fracture-tough, corrosion-resistant bearing steels

    NASA Technical Reports Server (NTRS)

    Olson, Gregory B.

    1990-01-01

    The fundamental principles allowing design of stainless bearing steels with enhanced toughness and stress corrosion resistance has involved both investigation of basic phenomena in model alloys and evaluation of a prototype bearing steel based on a conceptual design exercise. Progress in model studies has included a scanning Auger microprobe (SAM) study of the kinetics of interfacial segregation of embrittling impurities which compete with the kinetics of alloy carbide precipitation in secondary hardening steels. These results can define minimum allowable carbide precipitation rates and/or maximum allowable free impurity contents in these ultrahigh strength steels. Characterization of the prototype bearing steel designed to combine precipitated austenite transformation toughening with secondary hardening shows good agreement between predicted and observed solution treatment response including the nature of the high temperature carbides. An approximate equilibrium constraint applied in the preliminary design calculations to maintain a high martensitic temperature proved inadequate, and the solution treated alloy remained fully austenitic down to liquid nitrogen temperature rather than transforming above 200 C. The alloy can be martensitically transformed by cryogenic deformation, and material so processed will be studied further to test predicted carbide and austenite precipitation behavior. A mechanistically-based martensitic kinetic model was developed and parameters are being evaluated from available kinetic data to allow precise control of martensitic temperatures of high alloy steels in future designs. Preliminary calculations incorporating the prototype stability results suggest that the transformation-toughened secondary-hardening martensitic-stainless design concept is still viable, but may require lowering Cr content to 9 wt. pct. and adding 0.5 to 1.0 wt. pct. Al. An alternative design approach based on strain-induced martensitic transformation during

  4. Tool Steel Heat Treatment Optimization Using Neural Network Modeling

    NASA Astrophysics Data System (ADS)

    Podgornik, Bojan; Belič, Igor; Leskovšek, Vojteh; Godec, Matjaz

    2016-11-01

    Optimization of tool steel properties and corresponding heat treatment is mainly based on trial and error approach, which requires tremendous experimental work and resources. Therefore, there is a huge need for tools allowing prediction of mechanical properties of tool steels as a function of composition and heat treatment process variables. The aim of the present work was to explore the potential and possibilities of artificial neural network-based modeling to select and optimize vacuum heat treatment conditions depending on the hot work tool steel composition and required properties. In the current case training of the feedforward neural network with error backpropagation training scheme and four layers of neurons (8-20-20-2) scheme was based on the experimentally obtained tempering diagrams for ten different hot work tool steel compositions and at least two austenitizing temperatures. Results show that this type of modeling can be successfully used for detailed and multifunctional analysis of different influential parameters as well as to optimize heat treatment process of hot work tool steels depending on the composition. In terms of composition, V was found as the most beneficial alloying element increasing hardness and fracture toughness of hot work tool steel; Si, Mn, and Cr increase hardness but lead to reduced fracture toughness, while Mo has the opposite effect. Optimum concentration providing high KIc/HRC ratios would include 0.75 pct Si, 0.4 pct Mn, 5.1 pct Cr, 1.5 pct Mo, and 0.5 pct V, with the optimum heat treatment performed at lower austenitizing and intermediate tempering temperatures.

  5. 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

  6. STEFINS: a steel freezing integral simulation program

    SciTech Connect

    Frank, M.V.

    1980-09-01

    STEFINS (STEel Freezing INtegral Simulation) is a computer program for the calculation of the rate of solidification of molten steel on solid steel. Such computations arize when investigating core melt accidents in fast reactors. In principle this problem involves a coupled two-dimensional thermal and hydraulic approach. However, by physically reasonable assumptions a decoupled approach has been developed. The transient solidification of molten steel on a cold wall is solved in the direction normal to the molten steel flow and independent from the solution for the molten steel temperature and Nusselt number along the direction of flow. The solutions to the applicable energy equations have been programmed in cylindrical and slab geometries. Internal gamma heating of steel is included.

  7. Mechanical properties of steels with a microstructure of bainite/martensite and austenite islands

    NASA Astrophysics Data System (ADS)

    Syammach, Sami M.

    martensite volume fraction increased the strength of the steel. Strain hardening results showed that increasing the martensite volume fraction increased the strain hardening exponent while bainite decreased the strain hardening behavior. Austenite was found to slightly increase the strain hardening behavior. Hole-expansion tests showed hole expansion ratios ranging from 20 pct to 45 pct. Increasing the bainite volume fraction was found to increase the hole-expansion ratio. Increasing the martensite volume fraction was found to decrease the hole-expansion ratio. Overall, each of the heat treatments resulted in a steel with attractive properties, and the results showed how the microstructure of bainite, martensite, and austenite influences the mechanical properties of this type of steels.

  8. Pitting corrosion of low-Cr austenitic stainless steels

    SciTech Connect

    Bullard, Sophie J.; Covino, Bernard S. Jr.

    1996-01-01

    The Albany Research Center has investigated the pitting corrosion resistance of experimental low-Cr stainless steels and several commercial stainless steels in chloride-containing aqueous and atmospheric environments. Previous research had shown the experimental alloys to be as corrosion resistant as commercial stainless steels in chloride-free acid environments. The alloys studied were Fe-8Cr-16Ni-5.5Si-1Cu-(0-1)Mo, 304 SS, and 316 SS. These alloys were examined by immersion and electrochemical tests in 3.5 wt. pct. NaCl and 6 wt.pct.FeCl{sub 3}. Results of these tests showed that the addition of one weight percent Mo improved the pitting resistance of the low-Cr alloy and that the Mo-containing experimental alloy was as resistant to pitting as the commercial alloys. Electrochemical tests did, however, show the experimental alloys to be slightly less resistant to pitting than the commercial alloys. Because of these results, the low-Cr alloy with one weight percent Mo and 304 SS were exposed for one year to a marine atmospheric environment on the coast of Oregon. The marine atmospheric corrosion resistance of the low-Cr alloy was found to be comparable to that for type 304 stainless steel.

  9. Static Strain Aging Behavior of a Manganese-Silicon Steel After Single and Multi-stage Straining

    NASA Astrophysics Data System (ADS)

    Seraj, P.; Serajzadeh, S.

    2016-03-01

    In this work, static strain aging behavior of an alloy steel containing high amounts of silicon and manganese was examined while the influences of initial microstructure and pre-strain on the aging kinetics were evaluated as well. The rate of strain aging in a low carbon steel was also determined and compared with that occurred in the alloy steel. The rates of static strain aging in the steels were defined at room temperature and at 95 °C by means of double-hit tensile testing and hardness measurements. In addition, three-stage aging experiments at 80 °C were carried out to estimate aging behavior under multi-pass deformation processing. The results showed that in-solution manganese and silicon atoms could significantly affect the aging behavior of the steel and reduce the kinetics of static strain aging as compared to the low carbon steel. The initial microstructure also played an important role on the aging behavior. The rapidly cooled steel having mean ferrite grain size of 9.7 μm showed the least aging susceptibility index during the aging experiments. Accordingly, the activation energies for static strain aging were calculated as 93.2 and 85.7 kJ/mole for the alloy steel having fine and coarse ferrite-pearlite structures, respectively while it was computed as 79.1 kJ/mole for the low carbon steel with ferrite mean grain size of about 16.2 μm.

  10. Loading Path Dependence of Forming Limit Diagram of a TRIP800 Steel

    SciTech Connect

    Choi, Kyoo Sil; Soulami, Ayoub; Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.

    2011-04-12

    In this paper, the microstructure-based finite element modeling method is used in investigating the loading path dependence of formability of transformation induced plasticity (TRIP) steels. For this purpose, the effects of different loading path on the forming limit diagrams (FLD) of TRIP steels are qualitatively examined using the representative volume element (RVE) of a commercial TRIP800 steel. First, the modeling method was introduced, where a combined isotropic/kinematic hardening rule is adopted for the constituent phases in order to rightly describe the cyclic deformation behaviors of TRIP steels during the forming process with combined loading paths which may include the unloading between the two consecutive loadings. Material parameters for the constituent phases remained the same as those in the authors’ previous study [1] except for some adjustments for the martensite phase due to the introduction of the new combined hardening rule. Based on the new material parameters and new hardening rule, the predicted deformation behaviors of the TRIP800 steel show quite similar qualitative trends to those reported in other experimental works. Pseudo-forming limit strain diagrams (Pseudo-FLD) for the TRIP800 steel were, then, obtained for various loading paths. The computational results show that, similar to other single phase materials, the TRIP800 steel shows very sensitive loading path dependence in the strain-based forming limit diagrams (strain-FLD), but does not in the stress-based forming limit diagrams (stress-FLD), and that the phase transformation does not have significant effects on the FLD for the TRIP800 steel. From the observations in this study, the current modeling methods can be used in examining the qualitative trends of FLD of TRIP steels under different loading paths/prestrains.

  11. 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.

  12. 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.

  13. Heavy metal adsorption changes of EAF steel slag after phosphorus adsorption.

    PubMed

    Song, Guanling; Cao, Lijing; Chen, Xiao; Hou, Wenhua; Wang, Qunhui

    2012-01-01

    A kind of electric arc furnace (EAF) steel slag was phosphated, and its isothermal and dynamic adsorptions of copper, cadmium, and lead ions were measured to determine if heavy metal adsorption changes after phosphorus adsorption. The surface area increased greatly after the slag was phosphated. Isothermal adsorption experiments showed that the theoretical Q(max) of the EAF steel slag on Cu(2+), Cd(2+), and Pb(2+) improved 59, 50, and 89% respectively after it was phosphated. Dynamic adsorption results showed that the greatest adsorption capacities of unit volume of Cu(2+), Cd(2+), and Pb(2+) were 2.2, 1.8, and 1.8 times that of the column packed with original EAF steel slag when the column was packed with phosphate EAF steel slag at the same heavy metal ion concentration. The breakthrough time, the exhaustion time and elution efficiency of the column also increased when the column was packed with phosphated EAF steel slag compared with that packed with original EAF steel slag. Phosphorus adsorption could further improve the heavy metal ion adsorption of the EAF steel slag.

  14. Nanosized MX Precipitates in Ultra-Low-Carbon Ferritic/Martensitic Heat-Resistant Steels

    NASA Astrophysics Data System (ADS)

    Yin, Feng-Shi; Jung, Woo-Sang

    2009-02-01

    Nanosized MX precipitates in ultra-low-carbon ferritic/martensitic heat-resistant 9Cr-W-Mo-VNbTiN steels were characterized by transmission electron microscope (TEM) using carbon film replicas. The steels were prepared by vacuum induction melting followed by hot forging and rolling into plates. The plates were normalized at 1100 °C for 1 hour, cooled in air, and tempered at 700 °C for 1 hour. The results show that bimodal nanosized MX precipitates distribute densely and homogeneously in the matrix within martensitic lath after normalizing-and-tempering heat treatment. The larger nanosized MX precipitates with the size of 30 to 50 nm are rich in Nb, while the smaller ones with the size of about 10 nm contain less Nb but more V. Small addition of Ti causes an increase in the number of the larger nanosized MX precipitates. The total number density of the nanosized MX precipitates in the ultra-low-carbon ferritic/martensitic steels is measured to be over 300/ μm2, much higher than that in conventional ferritic/martensitic steels. Short-term creep test results show that the ultra-low-carbon ferritic/martensitic steels with high dense nanosized MX precipitates have much higher creep rupture strength than conventional ASME-P92 steel. The strength degradation of the ultra-low-carbon ferritic/martensitic heat-resistant steels during creep is also discussed in this article.

  15. Application of laser in seam welding of dissimilar steel to aluminium joints for thick structural components

    NASA Astrophysics Data System (ADS)

    Meco, S.; Pardal, G.; Ganguly, S.; Williams, S.; McPherson, N.

    2015-04-01

    Laser welding-brazing technique, using a continuous wave (CW) fibre laser with 8000 W of maximum power, was applied in conduction mode to join 2 mm thick steel (XF350) to 6 mm thick aluminium (AA5083-H22), in a lap joint configuration with steel on the top. The steel surface was irradiated by the laser and the heat was conducted through the steel plate to the steel-aluminium interface, where the aluminium melts and wets the steel surface. The welded samples were defect free and the weld micrographs revealed presence of a brittle intermetallic compounds (IMC) layer resulting from reaction of Fe and Al atoms. Energy Dispersive Spectroscopy (EDS) analysis indicated the stoichiometry of the IMC as Fe2Al5 and FeAl3, the former with maximum microhardness measured of 1145 HV 0.025/10. The IMC layer thickness varied between 4 to 21 μm depending upon the laser processing parameters. The IMC layer showed an exponential growth pattern with the applied specific point energy (Esp) at a constant power density (PD). Higher PD values accelerate the IMC layer growth. The mechanical shear strength showed a narrow band of variation in all the samples (with the maximum value registered at 31.3 kN), with a marginal increase in the applied Esp. This could be explained by the fact that increasing the Esp results into an increase in the wetting and thereby the bonded area in the steel-aluminium interface.

  16. 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.

  17. Steel project fact sheet: Steel reheating for further processing

    SciTech Connect

    1998-04-01

    Steel reheating is an energy-intensive process requiring uniform temperature distribution within reheating furnaces. Historically, recuperators have ben used to preheat combustion air, thereby conserving energy. More recent innovations include oxygen enrichment and the use of regenerative burners, which provide higher preheat air temperatures than recuperators. These processes have limitations such as equipment deterioration, decreasing energy efficiency over time, high maintenance costs, and increased NO{sub x} emissions with increased air preheat temperature, unless special equipment is used. Praxair, Inc., supplier of oxygen and other industrial gases to the steel industry, proposes to introduce an innovative oxy-fuel burner technology (using 100% oxygen) to the steel reheating industry. Oxy-fuel combustion reduces or eliminates nitrogen in combustion air and substantially reduces waste heat carried out with flue gas. Based on technology currently used in the glass, hazardous waste, and aluminum industries, Praxair has developed and patented low temperature, oxy-fuel burners that can be used in high temperature industrial furnaces where temperature uniformity is critical and extremely low NO{sub x} emissions are desired. The technical goal of the project is to demonstrate the use of oxy-fuel burners in a slab reheat furnace while reducing energy consumption by 45% and NO{sub x} emissions by 90% within the converted furnace zones. Successful implementation of this technology also will eliminate the need to periodically replace recuperators and install NO{sub x} removal equipment.

  18. Recorded seismic response of a base-isolated steel bridge carrying a steel water pipe

    USGS Publications Warehouse

    Safak, E.; Brady, A.G.

    1989-01-01

    A set of strong motion records was obtained from the base-isolated Santa Ana River Pipeline Bridge during the magnitude 5.9 Whittier Narrows, California, earthquake of October 1, 1987. The analysis of the records show that the level of excitation was not strong enough to fully activate the base isolators. The dominant modes of the response are the translations of the abutment-bridge-pipe system in the longitudinal and transverse directions, and the bending of the steel truss between supports in the vertical direction.

  19. Electrochemical Behavior of 2205 Duplex Stainless Steel in NaCl Solution with Different Chromate Contents

    NASA Astrophysics Data System (ADS)

    Luo, H.; Dong, C. F.; Cheng, X. Q.; Xiao, K.; Li, X. G.

    2012-07-01

    The electrochemical behavior of 2205 duplex stainless steel in NaCl solution with different chromate contents were investigated by potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), Mott-Schottky analysis, and scanning electron microscope (SEM). The effect of chromate on passivity and pitting behavior of stainless steel was also studied. The results showed that pitting susceptibility as well as semiconducting properties of passive film is heavily dependent on the chromate concentration. There exists a critical chromate value (about 0.03 M in 1 M NaCl solutions) below which the pitting corrosion on the stainless steel would be inhibited and above which it would be accelerated.

  20. Microstructure and mechanical behavior of neutron irradiated ultrafine grained ferritic steel

    SciTech Connect

    Ahmad Alsabbagh; Apu Sarkar; Brandon Miller; Jatuporn Burns; Leah Squires; Douglas Porter; James I. Cole; K. L. Murty

    2014-10-01

    Neutron irradiation effects on ultra-fine grain (UFG) low carbon steel prepared by equal channel angular pressing (ECAP) has been examined. Counterpart samples with conventional grain (CG) sizes have been irradiated alongside with the UFG ones for comparison. Samples were irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) to 1.24 dpa. Atom probe tomography revealed manganese, silicon-enriched clusters in both ECAP and CG steel after neutron irradiation. X-ray quantitative analysis showed that dislocation density in CG increased after irradiation. However, no significant change was observed in UFG steel revealing better radiation tolerance.

  1. Effect of hydrogen on plastic strain localization and fracture of steels

    NASA Astrophysics Data System (ADS)

    Nadjozhkin, M. V.; Lunev, A. G.; Li, Yu V.; Barannikova, S. A.

    2016-02-01

    The effect of interstitial hydrogen atoms on the mechanical properties and plastic strain localization patterns in tensile tested specimens of low-carbon steels have been studied using a double exposure speckle photography technique. It is found that the mechanical properties of low-carbon steels are affected adversely by hydrogen embrittlement. The deformation diagrams were examined for the deformed samples of low-carbon steels. These are found to show all the plastic flow stages: the linear, parabolic and pre-failure stages would occur for the respective values of the exponent n from the Ludwik-Holomon equation.

  2. Stiffening of short small-size circular composite steel-concrete columns with shear connectors.

    PubMed

    Younes, Sherif M; Ramadan, Hazem M; Mourad, Sherif A

    2016-05-01

    An experimental program was conducted to investigate the effect of shear connectors' distribution and method of load application on load-displacement relationship and behavior of thin-walled short concrete-filled steel tube (CFT) columns when subjected to axial load. The study focused on the compressive strength of the CFT columns and the efficiency of the shear stud in distribution of the load between the concrete core and steel tube. The study showed that the use of shear connectors enhanced slightly the axial capacity of CFT columns. It is also shown that shear connectors have a great effect on load distribution between the concrete and steel tubes.

  3. Improvement of Mechanical Properties of Spheroidized 1045 Steel by Induction Heat Treatment

    NASA Astrophysics Data System (ADS)

    Kim, Minwook; Shin, Jung-Ho; Choi, Young; Lee, Seok-Jae

    2016-04-01

    The effects of induction heat treatment on the formation of carbide particles and mechanical properties of spheroidized 1045 steel were investigated by means of microstructural analysis and tensile testing. The induction spheroidization accelerated the formation of spherical cementite particles and effectively softened the steel. The volume fraction of cementite was found to be a key factor that affected the mechanical properties of spheroidized steels. Further tests showed that sequential spheroidization by induction and furnace heat treatments enhanced elongation within a short spheroidization time, resulting in better mechanical properties. This was due to the higher volume fraction of spherical cementite particles that had less diffusion time for particle coarsening.

  4. The role of cyclic plastic zone size on fatigue crack growth behavior in high strength steels

    NASA Astrophysics Data System (ADS)

    Korda, Akhmad A.; Miyashita, Y.; Mutoh, Y.

    2015-09-01

    The role of cyclic plastic zone in front of the crack tip was studied in high strength steels. Estimated plastic zone size would be compared with actual observation. Strain controlled fatigue tests of the steels were carried out to obtain cyclic stress-strain curves for plastic zone estimation. Observations of plastic zone were carried out using in situ SEM fatigue crack growth tests under a constant-ΔK. Hard microstructures in structural steels showed to inhibit the extent of plastic deformation around the crack tip. The rate of crack growth can be correlated with the size of plastic zone. The smaller the plastic zone size, the slower the fatigue crack growth.

  5. Grain boundary composition and associated hydrogen cracking of modified 4130 steels

    NASA Astrophysics Data System (ADS)

    Craig, Bruce D.

    1984-03-01

    Earlier work on AISI 4130 steels showed that phosphorus segregation to prior austenite grain boundaries was the primary cause for intergranular fracture of these steels when exposed to hydrogen. Reduction of P segregation to grain boundaries by removing the strong segregation couples of Mn-P and Si-P was expected to increase the hydrogen stress cracking resistance of 4130 type steels. Elimination of Mn and/or Si did reduce the concentration of P at prior austenite grain boundaries, but allowed segregation of S and N which acted in the same manner as P, promoting intergranular hydrogen stress cracking.

  6. General and Localized corrosion of Austenitic and Borated Stainless Steels in Simulated Concentrated Ground Waters

    SciTech Connect

    D. Fix; J. Estill; L. Wong; R. Rebak

    2004-05-28

    Boron containing stainless steels are used in the nuclear industry for applications such as spent fuel storage, control rods and shielding. It was of interest to compare the corrosion resistance of three borated stainless steels with standard austenitic alloy materials such as type 304 and 316 stainless steels. Tests were conducted in three simulated concentrated ground waters at 90 C. Results show that the borated stainless were less resistant to corrosion than the witness austenitic materials. An acidic concentrated ground water was more aggressive than an alkaline concentrated ground water.

  7. General and Localized Corrosion of Austenitic And Borated Stainless Steels in Simulated Concentrated Ground Waters

    SciTech Connect

    Estill, J C; Rebak, R B; Fix, D V; Wong, L L

    2004-03-11

    Boron containing stainless steels are used in the nuclear industry for applications such as spent fuel storage, control rods and shielding. It was of interest to compare the corrosion resistance of three borated stainless steels with standard austenitic alloy materials such as type 304 and 316 stainless steels. Tests were conducted in three simulated concentrated ground waters at 90 C. Results show that the borated stainless were less resistant to corrosion than the witness austenitic materials. An acidic concentrated ground water was more aggressive than an alkaline concentrated ground water.

  8. Inhibitive effects of palm kernel oil on carbon steel corrosion by alkaline solution

    NASA Astrophysics Data System (ADS)

    Zulkafli, M. Y.; Othman, N. K.; Lazim, A. M.; Jalar, A.

    2013-11-01

    The behavior of carbon steel SAE 1045 in 1 M NaOH solution containing different concentrations of palm kernel oil (PKO) has been studied by weight loss and polarization measurement. Results showed that the corrosion of carbon steel in NaOH solution was considerably reduced in presence of such inhibitors. The inhibition efficiency increases when concentration of inhibitor increase. Maximum inhibition efficiency (≈ 96.67%) is obtained at PKO concentration 8 v/v %. This result revealed that palm kernel oil can act as a corrosion inhibitor in an alkaline medium. Corrosion rates of carbon steel decrease as the concentration of inhibitor is increased.

  9. Wear behavior of AISI 1090 steel modified by pulse plasma technique

    SciTech Connect

    Ayday, Aysun; Durman, Mehmet

    2012-09-06

    AISI 1090 steel was pulse plasma treated (PPT) using a Molybdenum electrode. Two different pulse numbers were chosen to obtain modified layers of 20{+-}5 {mu}m thickness. The dry sliding wear studies performed on this steel with and without PPT against an alumina ball counterpart showed that the PPT improved the wear resistance. The pulse number of the PPT modified layer was found to be highly influential in imparting the wear resistance to this steel, due to enhancement of surface hardness depending on treatment time.

  10. Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

    NASA Astrophysics Data System (ADS)

    Aslani, Farhad; Nejadi, Shami

    2012-09-01

    Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths ( τ ( app)) and slip coefficient ( β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle ( ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers

  11. Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

    NASA Astrophysics Data System (ADS)

    Aslani, Farhad; Nejadi, Shami

    2012-09-01

    Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths (τ (app)) and slip coefficient (β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle (ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers

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

    PubMed

    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

    1993-03-01

    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.

  13. 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

  14. Longer Life for Steel Structures

    NASA Technical Reports Server (NTRS)

    1990-01-01

    IC 531 is a coating manufactured and marketed by Inorganic Coatings, Inc. The coating was developed by Goddard to protect structures at Kennedy Space Center. It is a high ratio potassium silicate formula. The coating is water based, nontoxic, and nonflammable. It generates no volatile organic compounds nor hazardous chemical waste, and bonds to steel in 30 minutes. At the present time, no one can say for sure how long IC 531's effective lifetime is. Some of the original Goddard test applications of 1976 are still going strong after lengthy exposure to the Sun, salt and moisture. Says IC in company literature: 'IC 531 offers virtually permanent protection for steel. We predict it will protect structures for well beyond 25 years. If necessary, it is infinitely maintainable; if damaged, it can easily be touched up with more IC 531.'

  15. Steel Industry Energy Bandwidth Study

    SciTech Connect

    none,

    2004-10-01

    ITP conducted a study on energy use and potential savings, or "bandwidth" study, in major steelmaking processes. Intended to provide a realistic estimate of the potential amount of energy that can be saved in an industrial process, the "bandwidth" refers to the difference between the amount of energy that would be consumed in a process using commercially available technology versus the minimum amount of energy needed to achieve those same results based on the 2nd law of thermodynamics. The Steel Industry Energy Bandwidth Study (PDF 133 KB) also estimates steel industry energy use in the year 2010, and uses that value as a basis for comparison against the minimum requirements. This energy savings opportunity for 2010 will aid focus on longer term R&D.

  16. Light microscopy of carbon steels

    SciTech Connect

    Samuels, L.E.

    1998-12-31

    Containing over 1,200 representative micrographs and the information and explanatory text that makes them really useful: composition, condition, etchant, and magnification, and more than 100 graphs and tables, this how to book not only gives everyday working examples, but also discusses the relationship between the constitution, metallurgy, and microstructure of various carbon steel products. Written by a renowned expert in metallography, this definitive work is a must for all those working in this area. Contents include: nomenclature of phases and constituents; phase transformations; low-carbon irons and steels; annealing and normalizing; spheroidization and graphitization; austenitization; transformation of austenite; tempering of martensite; welding; surface oxidation, decarburation; and oxidation scaling; glossary of terms; etching methods; conversion tables.

  17. Steel Industry Marginal Opportunity Analysis

    SciTech Connect

    none,

    2005-09-01

    The Steel Industry Marginal Opportunity Analysis (PDF 347 KB) identifies opportunities for developing advanced technologies and estimates both the necessary funding and the potential payoff. This analysis determines what portion of the energy bandwidth can be captured through the adoption of state-of-the-art technology and practices. R&D opportunities for addressing the remainder of the bandwidth are characterized and plotted on a marginal opportunity curve.

  18. Steel Collet For Welding Electrodes

    NASA Technical Reports Server (NTRS)

    Gilbert, Jeffrey L.; Gutow, David A.; Burley, Richard K.; Fogul, Irving

    1992-01-01

    Improved steel collet holds electrode for tungsten inert-gas welding but allows quick and easy replacement. Also ensures reliable arc starting. Slip-on compression ring compresses tapered section of body of collet around inner end of welding electrode. Collet mounted in receptacle below stack of lenses and filters in coaxial-vision welding torch. Blind hole in collet protects outermost lens from damage by electrode.

  19. 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.

  20. Steel slag carbonation in a flow-through reactor system: the role of fluid-flux.

    PubMed

    Berryman, Eleanor J; Williams-Jones, Anthony E; Migdisov, Artashes A

    2015-01-01

    Steel production is currently the largest industrial source of atmospheric CO2. As annual steel production continues to grow, the need for effective methods of reducing its carbon footprint increases correspondingly. The carbonation of the calcium-bearing phases in steel slag generated during basic oxygen furnace (BOF) steel production, in particular its major constituent, larnite {Ca2SiO4}, which is a structural analogue of olivine {(MgFe)2SiO4}, the main mineral subjected to natural carbonation in peridotites, offers the potential to offset some of these emissions. However, the controls on the nature and efficiency of steel slag carbonation are yet to be completely understood. Experiments were conducted exposing steel slag grains to a CO2-H2O mixture in both batch and flow-through reactors to investigate the impact of temperature, fluid flux, and reaction gradient on the dissolution and carbonation of steel slag. The results of these experiments show that dissolution and carbonation of BOF steel slag are more efficient in a flow-through reactor than in the batch reactors used in most previous studies. Moreover, they show that fluid flux needs to be optimized in addition to grain size, pressure, and temperature, in order to maximize the efficiency of carbonation. Based on these results, a two-stage reactor consisting of a high and a low fluid-flux chamber is proposed for CO2 sequestration by steel slag carbonation, allowing dissolution of the slag and precipitation of calcium carbonate to occur within a single flow-through system. PMID:25597686

  1. Steel slag carbonation in a flow-through reactor system: the role of fluid-flux.

    PubMed

    Berryman, Eleanor J; Williams-Jones, Anthony E; Migdisov, Artashes A

    2015-01-01

    Steel production is currently the largest industrial source of atmospheric CO2. As annual steel production continues to grow, the need for effective methods of reducing its carbon footprint increases correspondingly. The carbonation of the calcium-bearing phases in steel slag generated during basic oxygen furnace (BOF) steel production, in particular its major constituent, larnite {Ca2SiO4}, which is a structural analogue of olivine {(MgFe)2SiO4}, the main mineral subjected to natural carbonation in peridotites, offers the potential to offset some of these emissions. However, the controls on the nature and efficiency of steel slag carbonation are yet to be completely understood. Experiments were conducted exposing steel slag grains to a CO2-H2O mixture in both batch and flow-through reactors to investigate the impact of temperature, fluid flux, and reaction gradient on the dissolution and carbonation of steel slag. The results of these experiments show that dissolution and carbonation of BOF steel slag are more efficient in a flow-through reactor than in the batch reactors used in most previous studies. Moreover, they show that fluid flux needs to be optimized in addition to grain size, pressure, and temperature, in order to maximize the efficiency of carbonation. Based on these results, a two-stage reactor consisting of a high and a low fluid-flux chamber is proposed for CO2 sequestration by steel slag carbonation, allowing dissolution of the slag and precipitation of calcium carbonate to occur within a single flow-through system.

  2. SECM Study of Effect of Chromium Content on the Localized Corrosion Behavior of Low-Alloy Steels in Chloride Environment

    NASA Astrophysics Data System (ADS)

    Indira, K.; Nishimura, T.

    2016-10-01

    This paper investigates the effect of chromium (Cr) content (0, 1, 3 and 5% Cr) in epoxy-coated alloy steel against corrosion using in situ electrochemical techniques such as EIS and SECM in a 3% NaCl solution. The EIS results revealed that the epoxy-coated Cr steel exhibited higher impedance values than carbon steel, which is attributed to the greater resistance of Cr steel toward corrosion. Based on the cyclic voltammogram results, the tip potentials were set at -0.7, 0.04 and 0.60 V for determining the concentration of dissolved oxygen at cathodic region, and oxidation of Cr2+ and Fe2+ at anodic region, respectively. The SECM measurements showed that, the tip current in the anodic region has decreased with increase in Cr content of the sample, which indicates that the oxidation of Fe2+ and Cr2+ decreases (corrosion is reduced) with the increase in Cr content of the steel. Besides, 5% Cr steel can maintain the highest corrosion resistance, and 1 and 3% Cr steels have higher corrosion resistance than the 0% Cr steel. This higher corrosion resistance of Cr steel samples could be due to the formation of Cr-rich hydro-oxide layers [Cr(OH)3 as a corrosion product] on the surface of the samples. Thus, the epoxy-coated Cr alloy steel has greater corrosion resistance in a chloride-containing environment than the carbon steel. Hence, epoxy-coated Cr alloy steel can be successfully used as a construction material in structures.

  3. Effects of Manganese Content on Solidification Structures, Thermal Properties, and Phase Transformation Characteristics in Fe-Mn-Al-C Steels

    NASA Astrophysics Data System (ADS)

    Yang, Jian; Wang, Yu-Nan; Ruan, Xiao-Ming; Wang, Rui-Zhi; Zhu, Kai; Fan, Zheng-Jie; Wang, Ying-Chun; Li, Cheng-Bin; Jiang, Xiao-Fang

    2015-04-01

    To assist developments of the continuous-casting technology of Fe-Mn-Al-C steels, the solidification structures and the thermal properties of Fe-Mn-Al-C steel ingots with different manganese contents have been investigated and the phase transformation characteristics have been revealed by FactSage (CRCT-ThermFact Inc., Montréal, Canada). The results show that the thermal conductivity of the 0Mn steel is the highest, whereas the thermal conductivity of the 8Mn steel is slightly higher than that of the 17Mn steel. Increasing the manganese content promotes a columnar solidification structure and coarse grains in steel. With the increase of manganese content, the mass fraction of austenite phase is increased. Finally, a single austenite phase is formed in the 17Mn steel. The mean thermal expansion coefficients of the steels are in the range from 1.3 × 10-5 to 2.3 × 10-5 K-1, and these values increase with the increase of manganese content. The ductility of the 17Mn steel and the 8Mn steel are higher than 40 pct in the temperature range from 873 K to 1473 K (600 °C to 1200 °C), and the cracking during the straightening operation should be avoided. However, the ductility of the 0Mn steel is lower than 40 pct at 973 K and 1123 K (700 °C and 850 °C), which indicates that the temperature of the straightening operation during the continuous-casting process should be above 1173 K (900 °C). Manganese has the effect of enlarging the austenite phase region and reducing the δ-ferrite phase region and α-ferrite phase region. At the 2.1 mass pct aluminum level, the precipitate temperature of AlN is high. Thus, the formed AlN is too coarse to deteriorate the hot ductility of steel.

  4. SECM Study of Effect of Chromium Content on the Localized Corrosion Behavior of Low-Alloy Steels in Chloride Environment

    NASA Astrophysics Data System (ADS)

    Indira, K.; Nishimura, T.

    2016-08-01

    This paper investigates the effect of chromium (Cr) content (0, 1, 3 and 5% Cr) in epoxy-coated alloy steel against corrosion using in situ electrochemical techniques such as EIS and SECM in a 3% NaCl solution. The EIS results revealed that the epoxy-coated Cr steel exhibited higher impedance values than carbon steel, which is attributed to the greater resistance of Cr steel toward corrosion. Based on the cyclic voltammogram results, the tip potentials were set at -0.7, 0.04 and 0.60 V for determining the concentration of dissolved oxygen at cathodic region, and oxidation of Cr2+ and Fe2+ at anodic region, respectively. The SECM measurements showed that, the tip current in the anodic region has decreased with increase in Cr content of the sample, which indicates that the oxidation of Fe2+ and Cr2+ decreases (corrosion is reduced) with the increase in Cr content of the steel. Besides, 5% Cr steel can maintain the highest corrosion resistance, and 1 and 3% Cr steels have higher corrosion resistance than the 0% Cr steel. This higher corrosion resistance of Cr steel samples could be due to the formation of Cr-rich hydro-oxide layers [Cr(OH)3 as a corrosion product] on the surface of the samples. Thus, the epoxy-coated Cr alloy steel has greater corrosion resistance in a chloride-containing environment than the carbon steel. Hence, epoxy-coated Cr alloy steel can be successfully used as a construction material in structures.

  5. 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.

  6. Superplastic Forming of Duplex Stainless Steel for Aerospace Part

    NASA Astrophysics Data System (ADS)

    Lee, Ho-Sung; Yoon, Jong-Hoon; Yoo, Joon-Tae; Yi, Young-Moo

    2011-08-01

    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 °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.

  7. Superelastic viscous dampers for seismically resilient steel frame structures

    NASA Astrophysics Data System (ADS)

    Ozbulut, O. E.; Meguira, B.

    2014-04-01

    This study proposes a passive control device based on superelastic behavior of shape memory alloys (SMAs) and investigates the device performance for improving response of steel frame structures subjected to multi-level seismic hazards. The device, named as Superelastic Viscous Damper (SVD), exhibits both re-centering and energy-dissipating capabilities and consists of SMA elements and a viscoelastic (VE) damper. SMA elements are mainly used as recentering unit and the viscoelastic damper is employed as energy dissipation unit. The VE damper consists of two layers of VE material bonded with three steel plates. Energy is dissipated through the shear deformation of VE material. Each SMA element forms a continuous loop; wrapping the loops around the outer two plates improves compactness and efficiency. An analytical model of a three-story benchmark steel building with the installed SVDs is developed to determine the response of the structure under a ground motion input. A neuro-fuzzy model is used to capture nonlinear behavior of the SMA elements of the SVD. Nonlinear response history analyses are conducted at MCE level seismic hazard. A suite of 22 ground motion records is employed in dynamic analysis. Peak interstory drift, peak absolute floor acceleration, and residual story drift are selected as the primary demand parameters. Results shows that SVDs can effectively mitigate dynamic response of steel frame structures under strong ground motions and enhance their post-earthquake functionality.

  8. Plasma-polymerized thiophene films for enhanced rubber steel bonding

    NASA Astrophysics Data System (ADS)

    Delattre, James L.; d'Agostino, Riccardo; Fracassi, Francesco

    2006-03-01

    Thin films of plasma-polymerized thiophene (PPTh) were deposited on cold-rolled steel substrates to improve adhesion to rubber compounds. PPTh films were characterized by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and atomic force microscopy. The ratio of carbon-to-sulfur found in PPTh films is 4:1, suggesting the monomer structure is generally intact, which was supported by FT-IR absorptions characteristic of polymerized thiophene rings. However, some fragmentation did occur to give acetylenic and aliphatic groups. Steel-rubber adhesion measurements, performed in accordance with the ASTM 429-B peel test, strongly depended on cleaning and pretreatment methods as well as film thickness. Best results were obtained on polished steel samples that were cleaned with acid, pretreated with a hydrogen/argon plasma, then coated with 50 Å of PPTh film. These samples exhibited a peel force of 14.3 N/mm, which is comparable to that of polished brass control samples. Depth-profiling XPS analysis of the rubber-steel interface showed the existence of an iron sulfide layer which is likely responsible for the strong adhesion.

  9. 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.

  10. Effect of heat treatment and irradiation temperature on impact behavior of irradiated reduced-activation ferritic steels

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.

    1998-03-01

    Charpy tests were conducted on eight normalized-and-tempered reduced-activation ferritic steels irradiated in two different normalized conditions. Irradiation was conducted in the Fast Flux Test Facility at 393 C to {approx}14 dpa on steels with 2.25, 5, 9, and 12% Cr (0.1% C) with varying amounts of W, V, and Ta. The different normalization treatments involved changing the cooling rate after austenitization. The faster cooling rate produced 100% bainite in the 2.25 Cr steels, compared to duplex structures of bainite and polygonal ferrite for the slower cooling rate. For both cooling rates, martensite formed in the 5 and 9% Cr steels, and martensite with {approx}25% {delta}-ferrite formed in the 12% Cr steel. Irradiation caused an increase in the ductile-brittle transition temperature (DBTT) and a decrease in the upper-shelf energy. The difference in microstructure in the low-chromium steels due to the different heat treatments had little effect on properties. For the high-chromium martensitic steels, only the 5 Cr steel was affected by heat treatment. When the results at 393 C were compared with previous results at 365 C, all but a 5 Cr and a 9 Cr steel showed the expected decrease in the shift in DBTT with increasing temperature.

  11. A 30degree 'barrel shot' taken at track level showing operator's ...

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

    A 30-degree 'barrel shot' taken at track level showing operator's house in center of swing span and the track with timber ties. The ties are transverse (90-degree) to the track with each end resting on the bottom chord of the steel swing span truss, thus providing their support with live loads being transferred to the swing span truss bridge. - Bridgeport Swing Span Bridge, Spanning Tennessee River, Bridgeport, Jackson County, AL

  12. View southwest of 350ton crane, showing one of four castings ...

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

    View southwest of 350-ton crane, showing one of four castings which support a stationary, tapered steel girder structure called a "tower". This tower is located within an outer rotating framework designated as the "pintle" of the 350-ton crane. The whole crane pivots around bearing at the top of this tapered support tower. - Naval Base Philadelphia-Philadelphia Naval Shipyard, 350-Ton Hammerhead Crane, League Island, Philadelphia, Philadelphia County, PA

  13. MECHANISTIC UNDERSTANDING OF CAUSTIC CRACKING OF CARBON STEELS

    SciTech Connect

    Garcia-Diaz, B.; Roy, A.

    2009-10-19

    Liquid waste generated by the PUREX process for separation of nuclear materials is concentrated and stored in Type IV single-shell carbon steel tanks at the Savannah River Site (SRS). The Type IV tanks for this waste do not have cooling coils and have not undergone heat treatment to stress-relieve the tanks. After the waste is concentrated by evaporation, it becomes very alkaline and can cause stress corrosion cracking (SCC) and pitting corrosion of the tank materials. SRS has experienced leakage from non-stress-relieved waste tanks constructed of A285 carbon steel and pitting of A212 carbon steel tanks in the vapor space. An investigation of tank materials has been undertaken at SRS to develop a basic understanding of caustic SCC of A285 and A212 grade carbon steels exposed to aqueous solutions, primarily containing sodium hydroxide (NaOH), sodium nitrate (NaNO{sub 3}), and sodium nitrite (NaNO{sub 2}) at temperatures relevant to the operating conditions of both the F and H area plants. This report presents the results of this corrosion testing program. Electrochemical tests were designed using unstressed coupons in a simulated tank environment. The purpose of this testing was to determine the corrosion susceptibility of the tank materials as a function of chemical concentration, pH, and temperature. A285 and A516 (simulates A212 carbon steel) coupons were used to investigate differences in the corrosion of these carbon steels. Electrochemical testing included measurement of the corrosion potential and polarization resistance as well as cyclic potentiodynamic polarization (CPP) testing of coupons. From the CPP experiments, corrosion characteristics were determined including: corrosion potential (E{sub corr}), pitting or breakdown potential (E{sub pit}), and repassivation potential (E{sub prot}). CPP results showed no indications of localized corrosion, such as pitting, and all samples showed the formation of a stable passive layer as evidenced by the positive

  14. Load carrying capacity of RCC beams by replacing steel reinforcement bars with shape memory alloy bars

    NASA Astrophysics Data System (ADS)

    Bajoria, Kamal M.; Kaduskar, Shreya S.

    2016-04-01

    In this paper the structural behavior of reinforced concrete (RC) beams with smart rebars under two point loading system has been numerically studied, using Finite Element Method. The material used in this study is Super-elastic Shape Memory Alloys (SE SMAs) which contains nickel and titanium. In this study, different quantities of steel and SMA rebars have been used for reinforcement and the behavior of these models under two point bending loading system is studied. A comparison of load carrying capacity for the model between steel reinforced concrete beam and the beam reinforced with S.M.A and steel are performed. The results show that RC beams reinforced with combination of shape memory alloy and steel show better performance.

  15. Solidification structures grown under induced flow and continuous casting of steel

    NASA Technical Reports Server (NTRS)

    Tsavaras, A. A.

    1984-01-01

    The use of induced flow as a means to control solidification structures in strand cast steel is investigated. The quality problems in strand cast steel stemming from columnar growth can be partially controlled, by Electro Magnetic Stirring (EMS). Induced flow changes the normal morphology of dendrites. Solids grown under intense stirring conditions show both negative and positive segregation which is considered unacceptable by some steel producers. The inclusion size and population is strongly affected by induced flow (EMS). Laboratory and industrial data show substantial reduction in inclusion size and content, but the overall effect of flow on inclusions is affected by the particular type of flow patterns utilized in each case. Productivity and quality are raised substantially in steel strand casting by utilizing EMS.

  16. Carbide-Free Bainitic Weld Metal: A New Concept in Welding of Armor Steels

    NASA Astrophysics Data System (ADS)

    Krishna Murthy, N.; Janaki Ram, G. D.; Murty, B. S.; Reddy, G. M.; Rao, T. J. P.

    2014-12-01

    Carbide-free bainite, a fine mixture of bainitic ferrite and austenite, is a relatively recent development in steel microstructures. Apart from being very strong and tough, the microstructure is hydrogen-tolerant. These characteristics make it well-suited for weld metals. In the current work, an armor-grade quenched and tempered steel was welded such that the fusion zone developed a carbide-free bainitic microstructure. These welds showed very high joint efficiency and ballistic performance compared to those produced, as per the current industrial practice, using austenitic stainless steel fillers. Importantly, these welds showed no vulnerability to cold cracking, as verified using oblique Y-groove tests. The concept of carbide-free bainitic weld metal thus promises many useful new developments in welding of high-strength steels.

  17. Void formation and microstructural development in oxide dispersion strengthened ferritic steels during electron-irradiation

    NASA Astrophysics Data System (ADS)

    Saito, J.; Suda, T.; Yamashita, S.; Ohnuki, S.; Takahashi, H.; Akasaka, N.; Nishida, M.; Ukai, S.

    1998-10-01

    ODS ferritic steels (13Cr-0.5Ti-0.2Y 2O 3) were prepared by the mechanical alloying method followed by the hot extrusion and several heat treatments including recrystallization. ODS steels with different heat treatment and a ferritic/martensitic (F/M) steel for the reference were irradiated to 12 dpa at 670-770 K in HVEM. After recrystallization, the dislocation density decreased with increasing grain size, however, the oxide particles did not show any obvious change in the size and the number density. During the electron-irradiation the microstructure was relatively stable, i.e. oxide particles showed good stability and the dislocation density remained almost constant. A limited void formation was observed in the specimens, and the suppressive effect due to dislocations with high number density was confirmed. From these results, the behavior of microstructure and the limited void formation in ODS steels have been discussed.

  18. Mathematical modeling and validation of the carburizing of low carbon steels

    NASA Astrophysics Data System (ADS)

    García Mariaca, A.; Cendales, E. D.; Chamarraví, O.

    2016-02-01

    This paper shows the mathematical modeling of heat and mass transfer in transient state of cylindrical bars of low carbon steel subjected to carburizing process. The model solution for the two phenomena was performed using a one-dimensional analysis in the radius direction, using the numerical method of finite differences; also a sensitivity analysis by varying the coefficient of convective heat transfer (h) is performed. The modeling results show that this carburization steel is strongly dependent on h. These results suggest that if it can increase the value of h in this kind of process could reduce the time of process for this heat treatment. Additionally, an experimental procedure was established by carburization of a steel AISI SAE 1010, which develops cementing solid phase and the specimen steel and micrographic hardness profiles obtained from samples of the specimen analysis was performed, to determine the penetration depth of the carbon and validate this result over the values obtained by the computer model.

  19. Low-temperature mechanical and magnetic properties of the reduced activation martensitic steel

    NASA Astrophysics Data System (ADS)

    Ding, Hui-Li; Zhang, Tao; Gao, Rui; Wang, Xian-Ping; Fang, Qian-Feng; Liu, Chang-Song; Suo, Jin-Ping

    2015-09-01

    Mechanical and magnetic properties as well as their relationship in the reduced activation martensitic (RAM) steel were investigated in the temperature range from -90°C to 20°C. Charpy impact tests show that the ductile-to-brittle transition temperature (DBTT) of the RAM steel is about -60°C. Low-temperature tensile tests show that the yield strength, ultimate tensile strength and total elongation values increase as temperature decreases, indicating that the strength and plasticity below the DBTT are higher than those above the DBTT. The coercive field ( H C) in the scale of logarithm decreases linearly with the increasing temperature and the absolute value of the slope of ln H C versus temperature above the DBTT is obviously larger than that below the DBTT, also confirmed in the T91 steel. The results indicate that the non-destructive magnetic measurement is a promising candidate method for the DBTT detection of ferromagnetic steels.

  20. A Method for Imaging Steel Bars Behind a Ferrous Steel Boundary

    NASA Astrophysics Data System (ADS)

    Fernandes, B.; Miller, G.; Zaid, M.; Gaydecki, P.

    2006-03-01

    A system for detecting steel objects behind ferrous steel boundaries is described. It may be used to image steel reinforcing bars in concrete, where a steel sheet exists between the bars and the surface. The sensor comprises a transmitter, receiver and a dummy coil, which cancels cross-talk and enhances the signal from the bars. It is possible to penetrate a 2mm thick sheet at 125 Hz and image 16 mm diameter bars placed underneath.