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Sample records for steel thick plate

  1. Effect of Cadmium Plating Thickness on the Charpy Impact Energy of Hydrogen-Charged 4340 Steel

    NASA Astrophysics Data System (ADS)

    Es-Said, O. S.; Alcisto, J.; Guerra, J.; Jones, E.; Dominguez, A.; Hahn, M.; Ula, N.; Zeng, L.; Ramsey, B.; Mulazimoglu, H.; Li, Yong-Jun; Miller, M.; Alrashid, J.; Papakyriakou, M.; Kalnaus, S.; Lee, E. W.; Frazier, W. E.

    2016-07-01

    Hydrogen was intentionally introduced into ultra-high strength steel by cadmium plating. The purpose was to examine the effect of cadmium plate thickness and hence hydrogen on the impact energy of the steel. The AISI 4340 steel was austenitized at 1000 °C for 1 h, water quenched, and tempered at temperatures between 257 and 593 °C in order to achieve a range of targeted strength levels. The specimens were cadmium plated with 0.00508 mm (0.2 mils), 0.00762 mm (0.3 mils), and 0.0127 mm (0.5 mils). Results demonstrated that the uncharged specimens exhibited higher impact energy values when compared to the plated specimens at all tempering temperatures. The cadmium-plated specimens had very low Charpy impact values irrespective of their ultimate tensile strength values. The model of hydrogen transport by mobile dislocations to the fracture site appears to provide the most suitable explanation of the results.

  2. Effect of mechanical restraint on weldability of reduced activation ferritic/martensitic steel thick plates

    NASA Astrophysics Data System (ADS)

    Serizawa, Hisashi; Nakamura, Shinichiro; Tanaka, Manabu; Kawahito, Yousuke; Tanigawa, Hiroyasu; Katayama, Seiji

    2011-10-01

    As one of the reduced activation ferritic/martensitic steels, the weldability of thick F82H plate was experimentally examined using new heat sources in order to minimize the total heat input energy in comparison with TIG welding. A full penetration of 32 mm thick plate could be produced as a combination of a 12 mm deep first layer generated by a 10 kW fiber laser beam and upper layers deposited by a plasma MIG hybrid welding with Ar + 2%O shielding gas. Also, the effect of mechanical restraint on the weldability under EB welding of thick F82H plate was studied by using FEM to select an appropriate specimen size for the basic test. The appropriate and minimum size for the basic test of weldability under EB welding of 90 mm thick plate might be 200 mm in length and 400 mm in width where the welding length should be about 180 mm.

  3. Through-thickness fracture of a Ti-V-N plate steel

    NASA Astrophysics Data System (ADS)

    Dogan, B.; Boyd, J. D.

    1990-05-01

    The effects of microstructure on through-thickness fracture properties of a Ti-V-N plate steel have been determined directly by through-thickness tensile tests and indirectly by studying delamination fractures in longitudinal tensile and Charpy tests. The initiation of ductile fracture is primarily controlled by inclusions, but overall ductility is influenced by microstructure such that the tensile fracture strain is higher for ferrite-pearlite microstructures than for ferrite-bainite or ferrite-martensite. The cleavage fracture stress is lower for steels which have been rolled below Ar 3 and contain deformed ferrite than for steels finish rolled above Ar 3. Measurements of true stress and true strain for fracture initiation qualitatively fit a model which assumes cleavage fracture occurs at a critical stress, ductile rupture at a critical strain, and a transition fracture mode comprising ductile initiation followed by cleavage.

  4. Quasi-Rayleigh waves in butt-welded thick steel plate

    NASA Astrophysics Data System (ADS)

    Kamas, Tuncay; Giurgiutiu, Victor; Lin, Bin

    2015-03-01

    This paper discusses theoretical and experimental analyses of weld guided surface acoustic waves (SAW) through the guided wave propagation (GWP) analyses. The GWP analyses have been carried out by utilizing piezoelectric wafer active sensors (PWAS) for in situ structural inspection of a thick steel plate with butt weld as the weld bead is ground flush. Ultrasonic techniques are commonly used for validation of welded structures in many in-situ monitoring applications, e.g. in off-shore structures, in nuclear and pressure vessel industries and in a range of naval applications. PWAS is recently employed in such ultrasonic applications as a resonator as well as a transducer. Quasi-Rayleigh waves a.k.a. SAW can be generated in relatively thick isotropic elastic plate having the same phase velocity as Rayleigh waves whereas Rayleigh waves are a high frequency approximation of the first symmetric (S0) and anti-symmetric (A0) Lamb wave modes. As the frequency becomes very high the S0 and the A0 wave speeds coalesce, and both have the same value. This value is exactly the Rayleigh wave speed and becomes constant along the frequency i.e. Rayleigh waves are non-dispersive guided surface acoustic waves. The study is followed with weld-GWP tests through the pitch-catch method along the butt weld line. The tuning curves of quasi-Rayleigh wave are determined to show the tuning and trapping effect of the weld bead that has higher thickness than the adjacent plates on producing a dominant quasi-Rayleigh wave mode. The significant usage of the weld tuned and guided quasi-Rayleigh wave mode is essentially discussed for the applications in the in-situ inspection of relatively thick structures with butt weld such as naval offshore structures. The paper ends with summary, conclusions and suggestions for future work.

  5. Quasi-Rayleigh waves in butt-welded thick steel plate

    SciTech Connect

    Kamas, Tuncay E-mail: victorg@sc.edu Giurgiutiu, Victor E-mail: victorg@sc.edu Lin, Bin E-mail: victorg@sc.edu

    2015-03-31

    This paper discusses theoretical and experimental analyses of weld guided surface acoustic waves (SAW) through the guided wave propagation (GWP) analyses. The GWP analyses have been carried out by utilizing piezoelectric wafer active sensors (PWAS) for in situ structural inspection of a thick steel plate with butt weld as the weld bead is ground flush. Ultrasonic techniques are commonly used for validation of welded structures in many in-situ monitoring applications, e.g. in off-shore structures, in nuclear and pressure vessel industries and in a range of naval applications. PWAS is recently employed in such ultrasonic applications as a resonator as well as a transducer. Quasi-Rayleigh waves a.k.a. SAW can be generated in relatively thick isotropic elastic plate having the same phase velocity as Rayleigh waves whereas Rayleigh waves are a high frequency approximation of the first symmetric (S0) and anti-symmetric (A0) Lamb wave modes. As the frequency becomes very high the S0 and the A0 wave speeds coalesce, and both have the same value. This value is exactly the Rayleigh wave speed and becomes constant along the frequency i.e. Rayleigh waves are non-dispersive guided surface acoustic waves. The study is followed with weld-GWP tests through the pitch-catch method along the butt weld line. The tuning curves of quasi-Rayleigh wave are determined to show the tuning and trapping effect of the weld bead that has higher thickness than the adjacent plates on producing a dominant quasi-Rayleigh wave mode. The significant usage of the weld tuned and guided quasi-Rayleigh wave mode is essentially discussed for the applications in the in-situ inspection of relatively thick structures with butt weld such as naval offshore structures. The paper ends with summary, conclusions and suggestions for future work.

  6. High power laser welding of thick steel plates in a horizontal butt joint configuration

    NASA Astrophysics Data System (ADS)

    Atabaki, M. Mazar; Yazdian, N.; Ma, J.; Kovacevic, R.

    2016-09-01

    In this investigation, two laser-based welding techniques, autogenous laser welding (ALW) and laser welding assisted with a cold wire (LWACW), were applied to join thick plates of a structural steel (A36) in a horizontal narrow gap butt joint configuration. The main practical parameters including welding method and laser power were varied to get the sound weld with a requirement to achieve a full penetration with the reinforcement at the back side of weld in just one pass. The weld-bead shape, cross-section and mechanical properties were evaluated by profilometer, micro-hardness test and optical microscope. In order to investigate the stability of laser-induced plasma plume, the emitted optical spectra was detected and analyzed by the spectroscopy analysis. It was found that at the laser power of 7 kW a fully penetrated weld with a convex back side of weld could be obtained by the LWACW. The microstructural examinations showed that for the ALW the acicular ferrite and for the LWACW the pearlite were formed in the heat affected zone (HAZ). The prediction of microstructure based on continuous cooling transformation (CCT) diagram and cooling curves obtained by thermocouple measurement were in good agreement with each other. According to the plasma ionization values obtained from the spectroscopy analysis the plume for both processes was recognized as dominated weakly ionized plasma including the main vaporized elemental composition. At the optimum welding condition (LWACW at the laser power of 7 kW) the fluctuation of the electron temperature was reduced. The spectroscopy analysis demonstrated that at the higher laser power more of the elemental compositions such as Mn and Fe were evaporated.

  7. The dynamic mechanical properties study on the sandwich panel of different thickness steel plate-foam aluminum core

    NASA Astrophysics Data System (ADS)

    Chang, Zhongliang; Zou, Guangping; Zhao, Weiling; Xia, Peixiu

    2009-12-01

    The foam aluminum belongs to multi-cell materials, and it has good mechanical performance, such as large deformation capacity and good energy absorption, and usually used as core material of sandwich panel, now it is widely used in automotive, aviation, aerospace and other fields, particularly suitable for various anti-collision structure and buffer structure. In this article, based on an engineering background, the INSTRON4505 electronic universal testing machine and split Hopkinson pressure bar (SHPB) were used for testing the static and dynamic mechanical properties of sandwich panel with different thickness steel plate- foam aluminum core, from the results we can see that the steel plate thickness has big influence on the stress-strain curve of the sandwich panel, and also takes the sandwich panel with 1mm steel panel to study the material strain rate dependence which under different high shock wave stress loaded, the results show that the sandwich panel is strain rate dependence material. And also, in order to get good waveforms in the SHPB experiment, the waveform shaped technique is used in the dynamic experiments, and the study of this paper will good to sandwich panel used in the engineering.

  8. The dynamic mechanical properties study on the sandwich panel of different thickness steel plate-foam aluminum core

    NASA Astrophysics Data System (ADS)

    Chang, Zhongliang; Zou, Guangping; Zhao, Weiling; Xia, Peixiu

    2010-03-01

    The foam aluminum belongs to multi-cell materials, and it has good mechanical performance, such as large deformation capacity and good energy absorption, and usually used as core material of sandwich panel, now it is widely used in automotive, aviation, aerospace and other fields, particularly suitable for various anti-collision structure and buffer structure. In this article, based on an engineering background, the INSTRON4505 electronic universal testing machine and split Hopkinson pressure bar (SHPB) were used for testing the static and dynamic mechanical properties of sandwich panel with different thickness steel plate- foam aluminum core, from the results we can see that the steel plate thickness has big influence on the stress-strain curve of the sandwich panel, and also takes the sandwich panel with 1mm steel panel to study the material strain rate dependence which under different high shock wave stress loaded, the results show that the sandwich panel is strain rate dependence material. And also, in order to get good waveforms in the SHPB experiment, the waveform shaped technique is used in the dynamic experiments, and the study of this paper will good to sandwich panel used in the engineering.

  9. Application of MMC model on simulation of shearing process of thick hot-rolled high strength steel plate

    NASA Astrophysics Data System (ADS)

    Dong, Liang; Li, Shuhui; Yang, Bing; Gao, Yongsheng

    2013-12-01

    Shear operation is widely used as the first step in sheet metal forming to cut the sheet or plate into the required size. The shear of thick hot-rolled High Strength Steel (HSS) requires large shearing force and the sheared edge quality is relatively poor because of the large thickness and high strength compared with the traditional low carbon steel. Bad sheared edge quality will easily lead to edge cracking during the post-forming process. This study investigates the shearing process of thick hot-rolled HSS plate metal, which is generally exploited as the beam of heavy trucks. The Modified Mohr-Coulomb fracture criterion (MMC) is employed in numerical simulation to calculate the initiation and propagation of cracks during the process evolution. Tensile specimens are designed to obtain various stress states in tension. Equivalent fracture strains are measured with Digital Image Correlation (DIC) equipment to constitute the fracture locus. Simulation of the tension test is carried out to check the fracture model. Then the MMC model is applied to the simulation of the shearing process, and the simulation results show that the MMC model predicts the ductile fracture successfully.

  10. Application of MMC model on simulation of shearing process of thick hot-rolled high strength steel plate

    SciTech Connect

    Dong, Liang; Li, Shuhui; Yang, Bing; Gao, Yongsheng

    2013-12-16

    Shear operation is widely used as the first step in sheet metal forming to cut the sheet or plate into the required size. The shear of thick hot-rolled High Strength Steel (HSS) requires large shearing force and the sheared edge quality is relatively poor because of the large thickness and high strength compared with the traditional low carbon steel. Bad sheared edge quality will easily lead to edge cracking during the post-forming process. This study investigates the shearing process of thick hot-rolled HSS plate metal, which is generally exploited as the beam of heavy trucks. The Modified Mohr-Coulomb fracture criterion (MMC) is employed in numerical simulation to calculate the initiation and propagation of cracks during the process evolution. Tensile specimens are designed to obtain various stress states in tension. Equivalent fracture strains are measured with Digital Image Correlation (DIC) equipment to constitute the fracture locus. Simulation of the tension test is carried out to check the fracture model. Then the MMC model is applied to the simulation of the shearing process, and the simulation results show that the MMC model predicts the ductile fracture successfully.

  11. An understanding of HSLA-65 plate steels

    NASA Astrophysics Data System (ADS)

    Sampath, K.

    2006-02-01

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

  12. Residual stress measurements on thick plate low-alloy steel narrow gap weldments by x-ray diffraction

    SciTech Connect

    Rund, C.O.; DiMascio, P.S.; Pangborn, R.N.; Snoha, D.J.

    1984-06-01

    A unique x-ray diffraction instrument for residual stress measurement has been developed that provides for speed, ease of measurement, accuracy, and economy of surface stress measurement. Application of this instrument with a material removal technique, e.g., electropolishing, has facilitated detailed, high resolution studies of three-dimensional stress fields. This paper describes the instrumentation and techniques applied to conduct the residual stress measurement and presents maps of the residual stress data obtained for the surfaces of a heavy 2 1/4 Cr 1 Mo steel plate weldment.

  13. A Study on the Application of Submerged Arc Welding for Thin Plate of A-Grade 3.2 Thickness Steel in Ship Structure

    NASA Astrophysics Data System (ADS)

    Lee, Jeong-Soo; Yun, Jin-Oh; Lim, Dong-Yong; Jang, Yong-Won; Kim, Bong-Joon; Oh, Chong-In

    2010-06-01

    This paper is focused on application submerged arc welding process, which offers many advantages compared to conventional CO2 welding process, for thin plate in ship structure. For this purpose, optimized welding conditions are determined according to combination of wire & flux, relationship between welding parameters, bead shapes and mechanical tests such as tensile, bend and hardness. Also finite element(FE) based numerical simulation of thermal history and welding residual stress in welded joint of A-grade 3.2 thickness steel has been checked to qualitative tendency in this paper. In conclusion our company applied to this method in work piece and it was no problem. From the result of this study, it makes substantial saving of time and manufacturing cost and raises the welding quality of product.

  14. Plating on stainless steel alloys

    SciTech Connect

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

    1981-09-11

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

  15. Elastic stability of thick auxetic plates

    NASA Astrophysics Data System (ADS)

    Lim, Teik-Cheng

    2014-04-01

    Auxetic materials and structures exhibit a negative Poisson’s ratio while thick plates encounter shear deformation, which is not accounted for in classical plate theory. This paper investigates the effect of a negative Poisson’s ratio on thick plates that are subjected to buckling loads, taking into consideration the shear deformation using Mindlin plate theory. Using a highly accurate shear correction factor that allows for the effect of Poisson’s ratio, the elastic stability of circular and square plates are evaluated in terms of dimensionless parameters, namely the Mindlin-to-Kirchhoff critical buckling load ratio and Mindlin critical buckling load factors. Results for thick square plates reveal that both parameters increase as the Poisson’s ratio becomes more negative. In the case of thick circular plates, the Mindlin-to-Kirchhoff critical buckling load ratios and the Mindlin critical buckling load factors increase and decrease, respectively, as the Poisson’s ratio becomes more negative. The results obtained herein show that thick auxetic plates behave as thin conventional plates, and therefore suggest that the classical plate theory can be used to evaluate the elastic stability of thick plates if the Poisson’s ratio of the plate material is sufficiently negative. The results also suggest that materials with highly negative Poisson’s ratios are recommended for square plates, but not circular plates, that are subjected to buckling loads.

  16. Stress measurement in thick plates using nonlinear ultrasonics

    SciTech Connect

    Abbasi, Zeynab E-mail: dozevin@uic.edu; Ozevin, Didem E-mail: dozevin@uic.edu

    2015-03-31

    In this paper the interaction between nonlinear ultrasonic characteristics and stress state of complex loaded thick steel plates using fundamental theory of nonlinear ultrasonics is investigated in order to measure the stress state at a given cross section. The measurement concept is based on phased array placement of ultrasonic transmitter-receiver to scan three angles of a given cross section using Rayleigh waves. The change in the ultrasonic data in thick steel plates is influenced by normal and shear stresses; therefore, three measurements are needed to solve the equations simultaneously. Different thickness plates are studied in order to understand the interaction of Rayleigh wave penetration depth and shear stress. The purpose is that as the thickness becomes smaller, the shear stress becomes negligible at the angled measurement. For thicker cross section, shear stress becomes influential if the depth of penetration of Rayleigh wave is greater than the half of the thickness. The influences of plate thickness and ultrasonic frequency on the identification of stress tensor are numerically studied in 3D structural geometry and Murnaghan material model. The experimental component of this study includes uniaxial loading of the plate while measuring ultrasonic wave at three directions (perpendicular, parallel and angled to the loading direction). Instead of rotating transmitter-receiver pair for each test, a device capable of measuring the three angles is designed.

  17. Shear deformation in thick auxetic plates

    NASA Astrophysics Data System (ADS)

    Lim, Teik-Cheng

    2013-08-01

    This paper aims to understand the effect of auxeticity on shear deformation in thick plates. Three models for the shear correction factor of plates as a function of Poisson’s ratio were proposed: an analytical model, a cubic fit model and a modified model. Of these three, the cubic fit model exhibits the best accuracy over the entire range of Poisson’s ratio from -1 to 0.5. The extent of shear deformation is herein investigated using the example of uniformly loaded circular plates. It was found that the maximum deformation of such plates based on Mindlin theory approximates to those according to Kirchhoff theory when the Poisson’s ratio of the plate material is highly negative. When the Poisson’s ratio of the plate material is -1 and the edge of the plate is simply supported, the calculation of the maximum deflection by Mindlin theory simplifies into that by Kirchhoff theory. These results suggest that auxeticity reduces shear deformation in thick plates, permitting the use of classical plate theory for thick plates only if the plate material is highly auxetic.

  18. Growth defects in thick ion-plated coatings

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1975-01-01

    Industrial ion plating conditions were selected to deposit metallic coatings such as copper, gold, and chromium 2 micrometer thick on metal and glass substrates. The surface finishes of 304 stainless steel, copper, and brass were utilized with mechanically and electrolytically polished surfaces. Nodular growth occurred in these coatings during ion plating as revealed by scanning electron microscopy. Surface irregularities such as scratches, steps, ledges, and so forth are responsible for outward growth, the typical cone type, whereas surface contaminants and loosely settled foreign particles are responsible for lateral growth; namely, the extreme localized surface outgrowths. These defect crystallographic features create porosity in the coatings when subjected to stresses and strains.

  19. Thermal equivalency study for steel propulsion shafting and flat plate

    SciTech Connect

    Dikshit, V.A.; Atteridge, D.G.

    1994-12-31

    The electroslag strip surfacing (ESS) process despite its advantage of high deposition rates, low base metal dilutions, and uniform penetrations, over unknown in the United States and has only recently started to gain acceptance as a feasible process for surfacing on large components, e.g., propulsion shafting. Electroslag strip surfacing was made on service scale shaft and on various flat plates using the same surfacing materials and parameters. Thermal history measurements were made by chromel-alumel thermocouples mounted on the shaft and the flat plates. The data were collected by a computer-controlled data acquisition system and subsequently postprocessed using commercial spreadsheet/graphics software programs. The t{sub 8-5} cooling times for the shaft and the flat plates showed a strong dependence on the interpass preheat temperature, but was independent of the maximum temperature. The t{sub 8-5} cooling times for the shaft and flat plate of the same thickness, and for the 76 and 127 mm thick flat plates were found to match very closely. This led to the conclusion that the thermal history results for 127 mm thick shaft and 127 to 67 mm thick flat plates made from similar steels show thermal equivalence for ESS and provide the justification for using 67 to 127 mm thick plates instead of 127 mm thick service scale shafting for process characterization.

  20. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) The wall thickness, after forming of the inner container shell and 2:1 ellipsoidal heads must be not... thickness of plate in inches after forming. (b) The wall thickness after forming of the inner container... = Minimum thickness of plate in inches after forming. (c) The wall thickness after forming of...

  1. Variable thickness double-refracting plate

    DOEpatents

    Hadeishi, Tetsuo

    1976-01-01

    This invention provides an A.C., cyclic, current-controlled, phase retardation plate that uses a magnetic clamp to produce stress birefringence. It was developed for an Isotope-Zeeman Atomic Absorption Spectrometer that uses polarization modulation to effect automatic background correction in atomic absorption trace-element measurements. To this end, the phase retardation plate of the invention is a variable thickness, photoelastic, double-refracting plate that is alternately stressed and released by the magnetic clamp selectively to modulate specific components selected from the group consisting of circularly and plane polarized Zeeman components that are produced in a dc magnetic field so that they correspond respectively to Zeeman reference and transmission-probe absorption components. The polarization modulation changes the phase of these polarized Zeeman components, designated as .sigma. reference and .pi. absorption components, so that every half cycle the components change from a transmission mode to a mode in which the .pi. component is blocked and the .sigma. components are transmitted. Thus, the Zeeman absorption component, which corresponds in amplitude to the amount of the trace element to be measured in a sample, is alternately transmitted and blocked by a linear polarizer, while the circularly polarized reference components are continuously transmitted thereby. The result is a sinusoidally varying output light amplitude whose average corresponds to the amount of the trace element present in the sample.

  2. Vibration Analysis of Stepped Thickness Plates

    NASA Astrophysics Data System (ADS)

    Guo, S. J.; Keane, A. J.; Moshrefi-Torbati, M.

    1997-07-01

    Investigation has been made into various approaches for analyzing the vibration of plates with stepped thicknesses. First, attention has been paid to updating a classical approach for the analysis of such problems, correcting the boundary conditions cited in an earlier paper and dealing with the difficulties that can arise when calculating high order modes. Secondly, contribution has been made to improving the classical finite strip method (FSM) by replacing the "static" shape function of the strip element by a "dynamic" function. This leads to the development of a dynamic finite strip method which improves solution accuracy without compromising model size and which therefore is more efficient than the classical FSM. When compared with the finite element method (FEM), which is also considered here, the advantages of smaller model size and higher accuracy of the dynamic FSM are significant. In order to demonstrate the application of the above approaches, the modes of simply supported plates with uniform and stepped thicknesses have been analyzed. From this numerical study, it is noted that the updated classical approach can be used to obtain a solution for any order mode to any specified accuracy and is the most efficient approach considered in the present study. It is also noted that, compared with the FEM of similar solution accuracy, the dynamic finite strip method normally produces a much smaller model size, so that such calculations are significantly more efficient than for the FEM. The aim of this work is to establish methods for the analysis of stepped plates that might be used in optimization studies where speed of formulation and solution are at a premium. There are, of course, a number of other methods that could be used to tackle such problems, but they lie outside the scope of this work; see for example the papers of Liew and co-authors [1, 2].

  3. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  4. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  5. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  6. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

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

    PubMed

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

    2015-09-01

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

  8. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  9. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  10. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  11. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  12. 49 CFR 179.100-6 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ....; S = Minimum tensile strength of plate material in p.s.i., as prescribed in § 179.100-7; t = Minimum thickness of plate in inches after forming. (b) If plates are clad with material having tensile strength... determining thickness. If cladding material does not have tensile strength at least equal to the base...

  13. 49 CFR 179.100-6 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ....; S = Minimum tensile strength of plate material in p.s.i., as prescribed in § 179.100-7; t = Minimum thickness of plate in inches after forming. (b) If plates are clad with material having tensile strength... determining thickness. If cladding material does not have tensile strength at least equal to the base...

  14. 49 CFR 179.100-6 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....; S = Minimum tensile strength of plate material in p.s.i., as prescribed in § 179.100-7; t = Minimum thickness of plate in inches after forming. (b) If plates are clad with material having tensile strength... determining thickness. If cladding material does not have tensile strength at least equal to the base...

  15. 49 CFR 179.100-6 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ....; S = Minimum tensile strength of plate material in p.s.i., as prescribed in § 179.100-7; t = Minimum thickness of plate in inches after forming. (b) If plates are clad with material having tensile strength... determining thickness. If cladding material does not have tensile strength at least equal to the base...

  16. Perforation of HY-100 steel plates with long rod projectiles

    SciTech Connect

    Hanchak, S.J.; Altman, B.S.; Forrestal, M.J.

    1993-07-01

    The authors conducted perforation experiments with 4340 steel, rod projectiles and HY-100 steel, target plates at striking velocities between 80 and 370 m/s. Projectiles were machined to nominally 30-mm-diameter and 281-mm-length so they could be launched from a 30-mm-powder gun without sabots. The target plates were rigidly clamped at 305-mm diameter and had a nominal thickness of 10.2 mm. In addition to measuring striking and residual projectile velocities, they obtained back surface framing camera data that showed clearly the plate deformation and plug ejection process. An Imacon 792 camera provided up to 20 frames per experiment with an interframe time duration of 10 {mu}s. The modeling work is in progress, but they present a beam model that exhibits the features observed in the experiments.

  17. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-6 Thickness of plates. (a) The wall... after forming. (b) The wall thickness after forming of the inner container heads, if flanged and dished... plate in inches after forming. (c) The wall thickness after forming of the cylindrical section and...

  18. Design of a Variable Thickness Plate to Focus Bending Waves

    NASA Technical Reports Server (NTRS)

    Schiller, Noah H.; Lin, Sz-Chin Steven; Cabell, Randolph H.; Huang, Tony Jun

    2012-01-01

    This paper describes the design of a thin plate whose thickness is tailored in order to focus bending waves to a desired location on the plate. Focusing is achieved by smoothly varying the thickness of the plate to create a type of lens, which focuses structural-borne energy. Damping treatment can then be positioned at the focal point to efficiently dissipate energy with a minimum amount of treatment. Numerical simulations of both bounded and unbounded plates show that the design is effective over a broad frequency range, focusing traveling waves to the same region of the plate regardless of frequency. This paper also quantifies the additional energy dissipated by local damping treatment installed on a variable thickness plate relative to a uniform plate.

  19. Thickness dependence of the Casimir force between a magnetodielectric plate and a diamagnetic plate

    SciTech Connect

    Inui, Norio

    2011-11-15

    This paper examines the repulsive Casimir force between a magnetodielectric plate, with static permeability greater than static permittivity, and a diamagnetic plate. As the thickness of the magnetodielectric plate is decreased, the attractive component of the Casimir force decreases more than the repulsive one. This effect makes the net Casimir force repulsive, and a larger repulsive Casimir force is generated compared to the Casimir force between the plates with infinite thickness.

  20. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    NASA Astrophysics Data System (ADS)

    Paris, V.; Weiss, A.; Vizel, A.; Ran, E.; Aizik, F.

    2012-08-01

    In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by matching simulated and experimental velocity profiles of planar impact. A series of oblique ballistic experiments with x-ray monitoring was carried out to study the effect of obliquity angle and armor steel plate thickness on shattering behavior of the 14.5 mm API projectile. According to analysis of x-ray images the fragmentation level increases with both steel plate thickness and angle of inclination. The numerical modeling of the ballistic experiments was done using commercial finite element code, LS-DYNA. Dynamic response of high hardness (HH) armor steel was described using a modified Johnson-Cook strength and failure model. A series of simulations with various values of maximal principal tensile stress was run in order to capture the overall fracture behavior of the projectile's core. Reasonable agreement between simulated and x-ray failure pattern of projectile core has been observed.

  1. Overriding plate thickness control on subducting slab curvature

    NASA Astrophysics Data System (ADS)

    Holt, A.; Buffett, B. A.; Becker, T. W.

    2014-12-01

    The curvature of subducting lithosphere controls deformation due to bending at the trench, which results in a force that dissipates gravitational potential energy and may affect seismic coupling. We use 2-D, thermo-mechanical subduction models to explore the dependence of the radius of curvature on the thickness of the subducting and overriding plates for models with both viscous and effectively plastic lithospheric rheologies. Such a plastic rheology has been shown to reproduce the bending stresses/moment computed using a kinematic strain rate description and a laboratory derived composite rheology. Laboratory and numerical models show that the bending geometry of subducting slabs with a viscous rheology is strongly dependent on slab thickness; thicker plates have a larger radius of curvature. However, the curvature of subducting plates on Earth, illuminated by the distribution of earthquake hypocenters, shows little to no dependence on the plate thickness or age. Such an observation is instead compatible with plates that have a plastic rheology. Indeed, our numerical models show that the radius of curvature of viscous plates has a stronger dependence on subducting plate thickness than in equivalent plastic models. In viscous plates, the bending moment produces a torque, which balances the torque exerted by buoyancy. However, for the plastic plate case the bending moment saturates at a maximum value and so cannot balance the gravitational torque. The saturation of bending moment means that, (a) the radius of curvature of the bending region is not constrained by this torque balance, and, (b) other forces are required to balance the gravitational torque. We explore the role that the overriding plate could play in controlling the subducting plate curvature in plastic plate models where the bending stresses have saturated. For such plates, we find that increasing the thickness of the overriding plate causes the radius of curvature to increase. The same correlation is

  2. Perforation of HY-100 steel plates with 4340 R{sub c} 38 and T-250 maraging steel rod projectiles

    SciTech Connect

    Forrestal, M.J.; Hanchak, S.J.

    1998-05-25

    The authors conducted perforation experiments with 4340 Rc 38 and T-250 maraging steel, long rod projectiles and HY-100 steel target plates at striking velocities between 80 and 370 m/s. Flat-end rod projectiles with lengths of 89 and 282 mm were machined to nominally 30-mm-diameter so they could be launched from a 30-mm-powder gun without sabots. The target plates were rigidly clamped at a 305-mm-diameter and had nominal thicknesses of 5.3 and 10.5 mm. Four sets of experiments were conducted to show the effects of rod length and plate thickness on the measured ballistic limit and residual velocities. In addition to measuring striking and residual projectile velocities, they obtained framing camera data on the back surfaces of several plates that showed clearly the plate deformation and plug ejection process. They also present a beam model that exhibits qualitatively the experimentally observed mechanisms.

  3. Thick plate flexure. [for lithospheric models of Mars and earth

    NASA Technical Reports Server (NTRS)

    Comer, R. P.

    1983-01-01

    Analytical expressions are derived for the displacements and stresses due to loading of a floating, uniform, elastic plate of arbitrary thickness by a plane or axisymmetric harmonic load. The solution is exact except for assumptions of small strains and linear boundary conditions, and gravitation within the plate is neglected. For typical earth parameters its predictions are comparable to those of the usual thin plate theory frequently assumed in studies of lithospheric flexure, gravity and regional isostasy. Even for a very thick lithosphere, which may exist in some regions of Mars, the thin plate theory is a better approximation to the thick plate solution than the elastic half-space limit, except for short-wavelength loads.

  4. Transient motion of thick anisotropic plates

    NASA Technical Reports Server (NTRS)

    Nayfeh, Adnan H.; Taylor, Timothy W.

    1991-01-01

    Analyses are developed for the response of anisotropic plate strips to a transient load. The load is taken in the form of a line load of normal stress on the surface or within the body of the strip. The characteristic free vibrational modes of the strip are derived and used to derive the secular equation for this case in closed form and to isolate the mathematical conditions for symmetric and antisymmetric wave mode propagation in completely separate terms. The applied loads are expanded in terms of these normal modes and the response of the plate is obtained by superposition of the appropriate components. Material systems of higher symmetry are contained implicitly in the analysis.

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

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

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

  6. Rolling contact fatigue life of chromium ion plated 440C bearing steel

    NASA Technical Reports Server (NTRS)

    Bhat, B. N.; Davis, J. H.

    1985-01-01

    Rolling contact fatigue (RCF) test specimens of heat treated 440C bearing steel were chromium ion plated in thicknesses from 0.1 to 8.0 micron and tested in RCF tester using 700 ksi maximum Hertzian stress. Heavy coatings, greater than about 5 micron in thickness, peeled off or spalled readily, whereas thin coatings, less than 3 micron thick, were tenacious and did not come off. Furthermore, significant improvement in RCF life was obtained with thin chromium ion plated test specimens. The average increase in B10 life was 75% compared with unplated 440C. These preliminary results indicate that ion plating is a promising way to improve bearing life.

  7. 49 CFR 179.400-8 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the following formula, whichever is greater: t = 1.83 Pd / 2SE Where: t = minimum thickness of plate.... (a) The minimum wall thickness, after forming, of the inner shell and any 2:1 ellipsoidal head for the inner tank must be that specified in § 179.401-1, or that calculated by the following...

  8. 49 CFR 179.400-8 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the following formula, whichever is greater: t = 1.83 Pd / 2SE Where: t = minimum thickness of plate.... (a) The minimum wall thickness, after forming, of the inner shell and any 2:1 ellipsoidal head for the inner tank must be that specified in § 179.401-1, or that calculated by the following...

  9. 49 CFR 179.400-8 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the following formula, whichever is greater: t = 1.83 Pd / 2SE Where: t = minimum thickness of plate.... (a) The minimum wall thickness, after forming, of the inner shell and any 2:1 ellipsoidal head for the inner tank must be that specified in § 179.401-1, or that calculated by the following...

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

    NASA Technical Reports Server (NTRS)

    1966-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  12. Oblique Perforation of Thick Metallic Plates by Rigid Projectiles

    NASA Astrophysics Data System (ADS)

    Chen, Xiaowei; Li, Qingming; Fan, Saucheong

    2006-08-01

    Oblique perforation of thick metallic plates by rigid projectiles with various nose shapes is studied in this paper. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose, are considered in the proposed analytical model. It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers, i.e., the impact function, the geometry function of projectile, the non-dimensional thickness of target and the impact obliquity. Explicit formulae are obtained to predict the ballistic limit, residual velocity and directional change for the oblique perforation of thick metallic plates. The proposed model is able to predict the critical condition for the occurrence of ricochet. The proposed model is validated by comparing the predictions with other existing models and independent experimental data.

  13. Ultrasonic Butt Welding of Aluminum, Copper and Steel Plate Specimens

    NASA Astrophysics Data System (ADS)

    Tsujino, Jiromaru; Ueoka, Tetsugi; Fujita, Yuki; Watanabe, Ichiro

    1994-05-01

    Characteristics of ultrasonic butt welding of the same and of different metal plates are studied. The ultrasonic vibration source used has eight 15-kHz bolt-clamped Langevin-type lead-zircon-titanate (PZT) transducers of 60 mm diameter and is driven by a 50-kW static induction thyristor power amplifier. Welding specimens of aluminum, copper and steel plates of 6 mm thickness are successfully joined end-to-end with weld strength almost equal to that of an aluminum specimen. The input power required for aluminum, aluminum and copper, and aluminum and steel plates are about 5 kW/cm2, 5.5 kW/cm2 and 3.5 kW/cm2, respectively. The measured temperature rise at the specimen side surface and elongation of the welded specimen during a tensile test correspond to weld strength. The hardness distributions along the weldment of welded specimens are measured and the maximum temperature rise in an aluminum welding specimen is estimated to be over 480°C from the reduction of hardness at a welding specimen surface.

  14. 49 CFR 179.400-8 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the outer jacket shell may not be less than 7/16 inch. The minimum wall thickness, after forming, of the outer jacket heads may not be less than 1/2 inch and they must be made from steel specified in § 179.16(c). The annular space is to be evacuated, and the cylindrical portion of the outer...

  15. Propagation of thickness-twist waves in elastic plates with periodically varying thickness and phononic crystals.

    PubMed

    Zhu, Jun; Chen, Weiqiu; Yang, Jiashi

    2014-09-01

    We study the propagation of thickness-twist (TT) waves in a crystal plate of AT-cut quartz with periodically varying, piecewise constant thickness. The scalar differential equation by Tiersten and Smythe is employed. The problem is found to be mathematically equivalent to the motion of an electron in a periodic potential field governed by Schrodinger's equation. An analytical solution is obtained. Numerical results show that the eigenvalue (frequency) spectrum of the waves has a band structure with allowed and forbidden bands. Therefore, for TT waves, plates with periodically varying thickness can be considered as phononic crystals. The effects of various parameters on the frequency spectrum are examined. PMID:24924785

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

    DOEpatents

    Howard, Stanley R.; Korinko, Paul S.

    2008-05-27

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

  17. Practical method for diffusion welding of steel plate in air.

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    Description of a simple and easily applied method of diffusion welding steel plate in air which does not require a vacuum furnace or hot press. The novel feature of the proposed welding method is that diffusion welds are made in air with deadweight loading. In addition, the use of an autogenous (self-generated) surface-cleaning principle (termed 'auto-vac cleaning') to reduce the effects of surface oxides that normally hinder diffusion welding is examined. A series of nine butt joints were diffusion welded in thick sections of AISI 1020 steel plate. Diffusion welds were attempted at three welding temperatures (1200, 1090, and 980 C) using a deadweight pressure of 34,500 N/sq m (5 psi) and a two-hour hold time at temperature. Auto-vac cleaning operations prior to welding were also studied for the same three temperatures. Results indicate that sound welds were produced at the two higher temperatures when the joints were previously fusion seal welded completely around the periphery. Also, auto-vac cleaning at 1200 C for 2-1/2 hours prior to diffusion welding was highly beneficial, particularly when subsequent welding was accomplished at 1090 C.

  18. Effect of preheat on residual stress distributions in arc-welded mild steel plates

    SciTech Connect

    Adedayo, S.M.; Adeyemi, M.B.

    2000-02-01

    Residual stress distribution in the longitudinal and transverse directions on a 6-mm-thick arc-welded mild steel plate was experimentally examined with and without initial preheat. Stress measurements were completed by monitoring strain changes on mounted strain gauges resulting from successive milling of the welded plate specimens. Machining stresses were also compensated for by carrying out measurements of strain changes due to milling operation of a stress-free unwelded annealed mild steel plate. High tensile residual stresses exist close to the weld line in both longitudinal and transverse stresses. Maximum longitudinal residual stress values existing close to the weld line are reduced (between 50 and 75%) due to the effect of initial metal preheat of 200 C of the welded steel plate.

  19. 49 CFR 179.400-8 - Thickness of plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Thickness of plates. 179.400-8 Section 179.400-8 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank...

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

    NASA Astrophysics Data System (ADS)

    Cho, Hyun; Yun, Young-Hoon

    2013-08-01

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

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

    PubMed

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

    1994-10-01

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

  2. 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.

  3. VIEW OF STEEL PLATE DOOR IN NUCLEAR PHYSICS LABORATORY, BETWEEN ...

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

    VIEW OF STEEL PLATE DOOR IN NUCLEAR PHYSICS LABORATORY, BETWEEN LABORATORY AND SP-SE REACTOR ROOM,LEVEL -15’, LOOKING NORTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

  4. Lamb and SH wave transducer arrays for the inspection of large areas of thick plates

    NASA Astrophysics Data System (ADS)

    Wilcox, P.; Lowe, M.; Cawley, P.

    2000-05-01

    The motivation for this work is to develop a rapid inspection system for large steel plates, such as those which the floors and walls of oil storage tanks are constructed from. One approach to inspecting plates using guided ultrasonic waves, is to design a transduction system which uses monolithic devices such as wedge transducers, inter-digital transducers or meander coil electro-magnetic acoustic transducers (EMATs). Unfortunately, in order to achieve a given level of performance at a particular operating point on the dispersion curves, the physical dimensions of a monolithic transducer must be scaled in proportion to the thickness of plate under inspection. This renders the use of monolithic devices on thicker plates increasingly impractical for several reasons, not least because of the cost and difficulties involved in manufacturing large devices. Also, particular monolithic devices are limited to a small range of applications since they are generally designed to be sensitive to a particular wavelength and to be either unfocused or have a fixed focal length. A more attractive solution is to use an array device containing a number of elements which behave individually as point transducers. By controlling the elements individually, wavelength selection, beam steering and focusing can all be performed by post processing the same set of test data. Encouraging experimental results obtained using this technique will be shown for several array designs which operate on 5-10 mm thick plates.

  5. Incremental ECAP of thick continuous plates - machine and initial trials

    NASA Astrophysics Data System (ADS)

    Rosochowski, A.; Olejnik, L.

    2014-08-01

    Incremental ECAP (I-ECAP) can be used for SPD of continuous bars, plates and sheets. This paper describes design, construction and preliminary trials of a prototype machine capable of processing thick continuous plates. To increase productivity, a two-turn I-ECAP is used, which is equivalent to route C in conventional one-turn ECAP. The machine has a reciprocating punch inclined at 45°, a clamp holding the plate in the die during deformation and a feeder incrementally feeding the plate when it is not deformed; all these devices are driven by hydraulic actuators controlled by a PLC. The machine is capable of deforming materials at room temperature as well as elevated temperatures. The die is heated with electric heaters. The machine has also an integrated cooling system and a lubrication system. The material used for the initial trials was Al 1050 plate (10×50×1000) conversion coated with calcium aluminate and lubricated with dry soap. The process was carried out at room temperature using 1.6 mm feeding stroke and a low cycle frequency of approximately 0.2 Hz. The UFG structure after the first pass of the process revealed by STEM confirms process feasibility.

  6. Electroless nickel plating on stainless steels and aluminum

    NASA Technical Reports Server (NTRS)

    1966-01-01

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

  7. 22. TRANSPORTING STEEL FLOOR PLATES ON HAND CART TO NORTH ...

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

    22. TRANSPORTING STEEL FLOOR PLATES ON HAND CART TO NORTH END OF BRIDGE. NOTE RETAINING ANGLE FOR SURFACING AT CUT-SIDE EDGE OF FLOOR PLATES. NOTE TUNNELS IN TOP OF ROCK FACE FOR MAIN CABLES - Kaibab Trail Suspension Bridge, Spanning Colorado River, Grand Canyon, Coconino County, AZ

  8. Thermal Stress Cracking of Slide-Gate Plates in Steel Continuous Casting

    NASA Astrophysics Data System (ADS)

    Lee, Hyoung-Jun; Thomas, Brian G.; Kim, Seon-Hyo

    2016-04-01

    The slide-gate plates in a cassette assembly control the steel flow through the tundish nozzle, and may experience through-thickness cracks, caused by thermal expansion and/or mechanical constraint, leading to air aspiration and safety concerns. Different mechanisms for common and rare crack formation are investigated with the aid of a three-dimensional finite-element model of thermal mechanical behavior of the slide-gate plate assembly during bolt pretensioning, preheating, tundish filling, casting, and cooling stages. The model was validated with previous plant temperature measurements of a ladle plate during preheating and casting, and then applied to a typical tundish-nozzle slide-gate assembly. The formation mechanisms of different types of cracks in the slide-gate plates are investigated using the model and evaluated with actual slide-gate plates at POSCO. Common through-thickness radial cracks, found in every plate, are caused during casting by high tensile stress on the outside surfaces of the plates, due to internal thermal expansion. In the upper plate, these cracks may also arise during preheating or tundish filling. Excessive bolt tightening, combined with thermal expansion during casting may cause rare radial cracks in the upper and lower plates. Rare radial and transverse cracks in middle plate appear to be caused during tundish filling by impingement of molten steel on the middle of the middle plate that generates tensile stress in the surrounding refractory. The mechanical properties of the refractory, the bolt tightening conditions, and the cassette/plate design are all important to service life.

  9. The Influence of Pre-existing Deformation on GMA Welding Distortion in Thin Steel Plates

    NASA Astrophysics Data System (ADS)

    Davies, C. M.; Ahn, J.; Tsunori, M.; Dye, D.; Nikbin, K. M.

    2015-01-01

    Weld distortion is particularly problematic for large thin structures that are used in the assembly of ships. The drive toward lighter ships and thinner plate is restricted by the significant increase in distortion as the plate thickness decreases. The influence of pre-existing deformation in the plates to be joined on the resultant distortion in gas metal arc welded structure has been studied. DH-36 steel plate surface profiles were measured before and after the butt welding of two plates 1000 × 500 × 4 mm in size. Three dimensional finite element models that incorporate the initial plate profile have been created to simulate the welding process and to examine the relationship between the final welded plate profiles and the initial deformation present in the plates. Both symmetric and asymmetric models were considered. A significant variation in the unwelded base plates' initial distortion was observed. Generally, it has been found that if an out-of-plane deformation exists in a plate prior to welding, the level of distortion further increases in the same direction following welding. The final distortions are strongly related to the initial plate profiles. The residual stress distributions in the plates are also to some extent affected by the level of distortion initially present.

  10. Optimal steel thickness combined with computed radiography for portal imaging of nasopharyngeal cancer patients

    SciTech Connect

    Wu Shixiu; Jin Xiance; Xie Congying; Cao Guoquan

    2005-10-15

    The poor image quality of conventional metal screen-film portal imaging system has long been of concern, and various methods have been investigated in an attempt to enhance the quality of portal images. Computed radiography (CR) used in combination with a steel plate displays image enhancement. The optimal thickness of the steel plate had been studied by measuring the modulation transfer function (MTF) characteristics. Portal images of nasopharyngeal carcinoma patients were taken by both a conventional metal screen-film system and this optimal steel and CR plate combination system. Compared with a conventional metal screen-film system, the CR-metal screen system achieves a much higher image contrast. The measured modulation transfer function (MTF) of the CR combination is greater than conventional film-screen portal imaging systems and also results in superior image performance, as demonstrated by receiver operator characteristic (ROC) analysis. This optimal combination steel CR plate portal imaging system is capable of producing high contrast portal images conveniently.

  11. Production of high strength TMCP steel plate for offshore structures

    SciTech Connect

    Yoshida, Yuzuru; Tamehiro, Hiroshi; Chijiiwa, Rikio; Funato, Kazuo; Doi, Naoki; Tanaka, Kazuaki; Kibe, Masaomi

    1993-12-31

    Titanium-oxide bearing steel (Ti-O steel), which has improved toughness in the heat-affected zone (HAZ) by utilizing intragranular ferrite (IGF), has been developed, and successfully put into commercial production. This was also the first application of yield strength (YS) 420 N/mm{sup 2} class TMCP steel plates to offshore structures. In the Ti-O steel, IGF grows radially from Ti-oxides finely dispersed in the steel as nuclei when HAZ transforms from austenite to ferrite after welding, and thus the microstructure of the HAZ is remarkably refined. As Ti-oxide particles are chemically stable even in the region near the fusion line which was reheated to a high-temperature above 1,350 C, control of the microstructure is possible in the entire HAZ and excellent crack tip opening displacement (CTOD) properties can be obtained. By applying Ti-O steel, Nippon Steel has succeeded in the mass production (approximately 9,000 tons) of YS 420 N/mm{sup 2} class TMCP steel plate for offshore structures in the North Sea. In addition to high strength and strict CTOD properties, various other properties including low carbon equivalent, narrow YS range, etc., were required for this plate. In order to satisfy these requirements, it was necessary to take comprehensive measured in the entire production process including steel making, continuous casting and plate rolling. The Ti-O steel with low carbon equivalent satisfies the required strength and low-temperature toughness of the base material and exhibits excellent toughness in the CTOD and Charpy tests of the welded joints, and offers good field weldability. Furthermore, the YS was controlled within a narrow range of less than 100 N/mm{sup 2} by strictly controlling the range of chemical composition and the TMCP condition.

  12. The technology and welding joint properties of hybrid laser-tig welding on thick plate

    NASA Astrophysics Data System (ADS)

    Shenghai, Zhang; Yifu, Shen; Huijuan, Qiu

    2013-06-01

    The technologies of autogenous laser welding and hybrid laser-TIG welding are used on thick plate of high strength lower alloy structural steel 10CrNiMnMoV in this article. The unique advantages of hybrid laser-TIG welding is summarized by comparing and analyzing the process parameters and welding joints of autogenous laser welding laser welding and hybrid laser-TIG welding. With the optimal process parameters of hybrid welding, the good welding joint without visible flaws can be obtained and its mechanical properties are tested according to industry standards. The results show that the hybrid welding technology has certain advantages and possibility in welding thick plates. It can reduce the demands of laser power, and it is significant for lowering the aspect ratio of weld during hybrid welding, so the gas in the molten pool can rise and escape easily while welding thick plates. Therefore, the pores forming tendency decreases. At the same time, hybrid welding enhances welding speed, and optimizes the energy input. The transition and grain size of the microstructure of hybrid welding joint is better and its hardness is higher than base material. Furthermore, its tensile strength and impact toughness is as good as base material. Consequently, the hybrid welding joint can meet the industry needs completely.

  13. Changes in Flat Plate Wake Characteristics Obtained With Decreasing Plate Thickness

    NASA Technical Reports Server (NTRS)

    Rai, Man Mohan

    2016-01-01

    The near and very near wake of a flat plate with a circular trailing edge is investigated with data from direct numerical simulations. Computations were performed for four different Reynolds numbers based on plate thickness (D) and at constant plate length. The value of ?/D varies by a factor of approximately 20 in the computations (? being the boundary layer momentum thickness at the trailing edge). The separating boundary layers are turbulent in all the cases. One objective of the study is to understand the changes in wake characteristics as the plate thickness is reduced (increasing ?/D). Vortex shedding is vigorous in the low ?/D cases with a substantial decrease in shedding intensity in the largest ?/D case (for all practical purposes shedding becomes almost intermittent). Other characteristics that are significantly altered with increasing ?/D are the roll-up of the detached shear layers and the magnitude of fluctuations in shedding period. These effects are explored in depth. The effects of changing ?/D on the distributions of the time-averaged, near-wake velocity statistics are discussed.

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

    SciTech Connect

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

    1994-06-01

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

  15. Analysis of a Thick Dichroic Plate with Arbitrarily Shaped Holes

    NASA Astrophysics Data System (ADS)

    Imbriale, W. A.

    2001-04-01

    A thick dichroic plate acts as a frequency selective surface (FSS) in that it is transparent at one frequency while at the same time reflective to other frequencies. It is used in the DSN to enable simultaneous multiple-frequency operation. Most of the plates currently in use were designed with programs that analyzed only the simple geometries, such as circular or rectangular holes. Since it is too expensive to experimentally determine the FSS parameters, only designs that could be accurately analyzed were chosen, and it is the primary reason why the recent FSS designs use rectangular holes. To achieve the sharp corners of the rectangular holes, it was necessary to use an electrical discharge machining (EDM) manufacturing technique. This manufacturing technique is expensive, and an important use of the arbitrary-shaped analysis is to enable designs that use rounded corners that are able to be manufactured by less expensive techniques. The analysis is accomplished by combining the finite-element method (FEM) for determining the waveguide modes of arbitrarily shaped guides with the method of moments and Floquet mode theory for periodic structures. The software was verified by comparison with previously measured and computed dichroic plates.

  16. Analysis of absorption performances of anechoic layers with steel plate backing.

    PubMed

    Meng, Hao; Wen, Jihong; Zhao, Honggang; Lv, Linmei; Wen, Xisen

    2012-07-01

    Rubber layers with air-filled cavities or local resonance scatters can be used as anechoic coatings. A lot of researches have focused on the absorption mechanism of the anechoic coatings. As the anechoic coatings are bonded to the hull of submarine, the vibration of the hull should not be neglected when the analysis of the absorption characters is carried out. Therefore, it is more reasonable to treat the anechoic coating and the backing as a whole when the acoustic performance is analyzed. Considering the effects of the steel plate backing, the sound absorption performances on different models of anechoic coatings are investigated in this paper. The Finite Element Method is used to illustrate the vibrational behaviors of the anechoic coatings under the steel backings by which the displacement contours is obtained for analysis. The theoretical results show that an absorption peak is induced by the resonance of the steel slab and rubber layer. At the frequency of this absorption peak, the steel plate and the coating vibrates longitudinally like a mass-spring system in which the steel slab serves for mass and the coating layer is the spring. To illuminate the effects of the steel slab backing on the acoustic absorption, the thicknesses of the steel slab and the anechoic layer are discussed. Finally, an experiment is performed and the results show a good agreement with the theoretical analysis. PMID:22779456

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

    SciTech Connect

    Zapp, P.E.

    2001-02-06

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

  18. Thermal distortion tests of aluminum and stainless steel plates

    SciTech Connect

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

    1993-06-25

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

  19. 2. DETAIL OF BUILDER'S PLATE: 'SUPERSTRUCTURE BUILT BY STROBEL STEEL ...

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

    2. DETAIL OF BUILDER'S PLATE: 'SUPERSTRUCTURE BUILT BY STROBEL STEEL CONSTRUCTION CO., CHICAGO, ILL., 1913, SUBSTRUCTURE BUILT BY FITZSIMONS & CONNELL D&D CO., CHICAGO, ILL.' - Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chicago River at Grand Avenue, Chicago, Cook County, IL

  20. 78 FR 7451 - Clad Steel Plate From Japan; Determination

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ..., 2012 (77 FR 5052) and determined on May 7, 2012 that it would conduct a full review (77 FR 37439, June..., 2012 (77 FR 38825). The hearing was held in Washington, DC, on December 6, 2012, and all persons who... COMMISSION Clad Steel Plate From Japan; Determination On the basis of the record \\1\\ developed in the...

  1. DETAIL OF STEEL PLATE SET INTO THE CONCRETE SLAB OF ...

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

    DETAIL OF STEEL PLATE SET INTO THE CONCRETE SLAB OF THE NORTH END OF THE ABOVE-GROUND PORTION. VIEW FACING NORTH - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, Battery Command Center, Ford Island, Pearl City, Honolulu County, HI

  2. 6. WORKMEN REPLACING STEEL PLATES IN FLUME NO. 10, ABOVE ...

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

    6. WORKMEN REPLACING STEEL PLATES IN FLUME NO. 10, ABOVE SAR-1. FLUME FOR SAR-3 WAS REBUILT AT THE SAME TIME. SCE negative no. 11776, May 1, 1926. Photograph by G. Haven Bishop. - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  3. Effect of Rolling Temperature and Ultrafast Cooling Rate on Microstructure and Mechanical Properties of Steel Plate

    NASA Astrophysics Data System (ADS)

    Ye, Qibin; Liu, Zhenyu; Yang, Yu; Wang, Guodong

    2016-07-01

    Microstructure can vary significantly through thickness after ultrafast cooling of rolled steel plates, impacting their mechanical properties. This study examined the microstructure, microstructural banding at centerline, and mechanical properties through thickness for different ultrafast cooling conditions and rolling temperatures. One set of steels (UC1 and UC2) were ultrafast-cooled (UFC) at 40 K/s after finish rolling at 1223 K and 1193 K (950 °C and 910 °C), respectively, while the second set (LC) was cooled by laminar cooling at 17 K/s after finish rolling at 1238 K (965 °C). UFC produced microstructural variation through thickness; highly dislocated lath-type bainitic ferrite was formed near the surface, whereas the primary microstructure was acicular ferrite and irregular polygonal ferrite in the interior of UC1 and UC2 steels, respectively. However, UFC has the advantage of suppression of microstructural banding in centerline segregation regions. The ferrite grain size in both UFC-cooled steels was refined to ~5 μm, increasing strength and toughness. The optimum combination of properties was obtained in UC2 steel with appropriate low finish rolling temperature, being attributed to the distinct microstructure resulting from work-hardened austenite before UFC.

  4. Study of Hypervelocity Projectile Impact on Thick Metal Plates

    SciTech Connect

    Roy, Shawoon K.; Trabia, Mohamed; O’Toole, Brendan; Hixson, Robert S.; Becker, Steven; Pena, Michael T.; Jennings, Richard; Somasoundaram, Deepak; Matthes, Melissa; Daykin, Edward P.; Machorro, Eric

    2016-01-01

    Hypervelocity impacts generate extreme pressure and shock waves in impacted targets that undergo severe localized deformation within a few microseconds. These impact experiments pose unique challenges in terms of obtaining accurate measurements. Similarly, simulating these experiments is not straightforward. This paper proposed an approach to experimentally measure the velocity of the back surface of an A36 steel plate impacted by a projectile. All experiments used a combination of a two-stage light-gas gun and the photonic Doppler velocimetry (PDV) technique. The experimental data were used to benchmark and verify computational studies. Two different finite-element methods were used to simulate the experiments: Lagrangian-based smooth particle hydrodynamics (SPH) and Eulerian-based hydrocode. Both codes used the Johnson-Cook material model and the Mie-Grüneisen equation of state. Experiments and simulations were compared based on the physical damage area and the back surface velocity. Finally, the results of this study showed that the proposed simulation approaches could be used to reduce the need for expensive experiments.

  5. Study of hypervelocity projectile impact on thick metal plates

    SciTech Connect

    Roy, Shawoon K.; Trabia, Mohamed; O’Toole, Brendan; Hixson, Robert S.; Becker, Steven; Pena, Michael T.; Jennings, Richard; Somasoundaram, Deepak; Matthes, Melissa; Daykin, Edward P.; Machorro, Eric

    2016-01-01

    Hypervelocity impacts generate extreme pressure and shock waves in impacted targets that undergo severe localized deformation within a few microseconds. These impact experiments pose unique challenges in terms of obtaining accurate measurements. Similarly, simulating these experiments is not straightforward. This paper proposed an approach to experimentally measure the velocity of the back surface of an A36 steel plate impacted by a projectile. All experiments used a combination of a two-stage light-gas gun and the photonic Doppler velocimetry (PDV) technique. The experimental data were used to benchmark and verify computational studies. Two different finite-element methods were used to simulate the experiments: Lagrangian-based smooth particle hydrodynamics (SPH) and Eulerian-based hydrocode. Both codes used the Johnson-Cook material model and the Mie-Grüneisen equation of state. Experiments and simulations were compared based on the physical damage area and the back surface velocity. Finally, the results of this study showed that the proposed simulation approaches could be used to reduce the need for expensive experiments.

  6. Study of hypervelocity projectile impact on thick metal plates

    DOE PAGESBeta

    Roy, Shawoon K.; Trabia, Mohamed; O’Toole, Brendan; Hixson, Robert S.; Becker, Steven; Pena, Michael T.; Jennings, Richard; Somasoundaram, Deepak; Matthes, Melissa; Daykin, Edward P.; et al

    2016-01-01

    Hypervelocity impacts generate extreme pressure and shock waves in impacted targets that undergo severe localized deformation within a few microseconds. These impact experiments pose unique challenges in terms of obtaining accurate measurements. Similarly, simulating these experiments is not straightforward. This paper proposed an approach to experimentally measure the velocity of the back surface of an A36 steel plate impacted by a projectile. All experiments used a combination of a two-stage light-gas gun and the photonic Doppler velocimetry (PDV) technique. The experimental data were used to benchmark and verify computational studies. Two different finite-element methods were used to simulate the experiments:more » Lagrangian-based smooth particle hydrodynamics (SPH) and Eulerian-based hydrocode. Both codes used the Johnson-Cook material model and the Mie-Grüneisen equation of state. Experiments and simulations were compared based on the physical damage area and the back surface velocity. Finally, the results of this study showed that the proposed simulation approaches could be used to reduce the need for expensive experiments.« less

  7. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of Carbon, Alloy, and Armor Steel Plate. 252.225-7030 Section 252.225-7030 Federal Acquisition... Acquisition of Carbon, Alloy, and Armor Steel Plate. As prescribed in 225.7011-3, use the following clause: Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate (DEC 2006) (a) Carbon, alloy, and...

  8. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of Carbon, Alloy, and Armor Steel Plate. 252.225-7030 Section 252.225-7030 Federal Acquisition... Acquisition of Carbon, Alloy, and Armor Steel Plate. As prescribed in 225.7011-3, use the following clause: Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate (DEC 2006) (a) Carbon, alloy, and...

  9. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of Carbon, Alloy, and Armor Steel Plate. 252.225-7030 Section 252.225-7030 Federal Acquisition... Acquisition of Carbon, Alloy, and Armor Steel Plate. As prescribed in 225.7011-3, use the following clause: Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate (DEC 2006) (a) Carbon, alloy, and...

  10. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of Carbon, Alloy, and Armor Steel Plate. 252.225-7030 Section 252.225-7030 Federal Acquisition... Acquisition of Carbon, Alloy, and Armor Steel Plate. As prescribed in 225.7011-3, use the following clause: Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate (DEC 2006) (a) Carbon, alloy, and...

  11. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of Carbon, Alloy, and Armor Steel Plate. 252.225-7030 Section 252.225-7030 Federal Acquisition... Acquisition of Carbon, Alloy, and Armor Steel Plate. As prescribed in 225.7011-3, use the following clause: Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate (DEC 2006) (a) Carbon, alloy, and...

  12. 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

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

    DOEpatents

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

    2007-07-24

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

  14. Effect of Backing Plate Thermal Property on Friction Stir Welding of 25-mm-Thick AA6061

    NASA Astrophysics Data System (ADS)

    Upadhyay, Piyush; Reynolds, Anthony

    2014-04-01

    By using backing plates made out of materials with widely varying thermal diffusivity this work seeks to elucidate the effects of the root side thermal boundary condition on weld process variables and resulting joint properties. Welds were made in 25.4-mm-thick AA6061 using ceramic, titanium, steel, and aluminum as backing plate (BP) material. Welds were also made using a "composite backing plate" consisting of longitudinal narrow strip of low diffusivity material at the center and two side plates of high diffusivity aluminum. Stir zone temperature during the welding was measured using two thermocouples spot welded at the core of the probe: one at the midplane height and another near the tip of the probe corresponding to the root of the weld. Steady state midplane probe temperatures for all the BPs used were found to be very similar. Near root peak temperature, however, varied significantly among weld made with different BPs all other things being equal. Whereas the near root and midplane temperature were the same in the case of ceramic backing plate, the root peak temperature was 318 K (45 °C) less than the midplane temperature in the case of aluminum BP. The trends of nugget hardness and grain size in through thickness direction were in agreement with the measured probe temperatures. Hardness and tensile test results show that the use of composite BP results in stronger joint compared to monolithic steel BP.

  15. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  16. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  17. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  18. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  19. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  20. Estimates of elastic plate thicknesses beneath large volcanos on Venus

    NASA Technical Reports Server (NTRS)

    Mcgovern, Patrick J.; Solomon, Sean C.

    1992-01-01

    Megellan radar imaging and topography data are now available for a number of volcanos on Venus greater than 100 km in radius. These data can be examined to reveal evidence of the flexural response of the lithosphere to the volcanic load. On Earth, flexure beneath large hotspot volcanos results in an annual topographic moat that is partially to completely filled in by sedimentation and mass wasting from the volcano's flanks. On Venus, erosion and sediment deposition are considered to be negligible at the resolution of Magellan images. Thus, it may be possible to observe evidence of flexure by the ponding of recent volcanic flows in the moat. We also might expect to find topographic signals from unfilled moats surrounding large volcanos on Venus, although these signals may be partially obscured by regional topography. Also, in the absence of sedimentation, tectonic evidence of deformation around large volcanos should be evident except where buried by very young flows. We use analytic solutions in axisymmetric geometry for deflections and stresses resulting from loading of a plate overlying an inviscid fluid. Solutions for a set of disk loads are superimposed to obtain a solution for a conical volcano. The deflection of the lithosphere produces an annular depression or moat, the extent of which can be estimated by measuring the distance from the volcano's edge to the first zero crossing or to the peak of the flexural arch. Magellan altimetry data records (ARCDRs) from data cycle 1 are processed using the GMT mapping and graphics software to produce topographic contour maps of the volcanos. We then take topographic profiles that cut across the annular and ponded flows seen on the radar images. By comparing the locations of these flows to the predicted moat locations from a range of models, we estimate the elastic plate thickness that best fits the observations, together with the uncertainty in that estimate.

  1. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... required bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed... pressure in psig; S = Minimum tensile strength of plate material in psi as prescribed in AAR...

  2. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... required bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed... pressure in psig; S = Minimum tensile strength of plate material in psi as prescribed in AAR...

  3. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... required bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed... pressure in psig; S = Minimum tensile strength of plate material in psi as prescribed in AAR...

  4. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...; P = Minimum required bursting pressure in psig; S = Minimum tensile strength of plate material in p... in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179.200-7; t... pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179.200-7;...

  5. Measurement of steel plate perforation tests with digital image correlation.

    SciTech Connect

    Cordova, Theresa Elena; Reu, Phillip L.; Vangoethem, Douglas J.

    2009-03-01

    The results of a series of punch-through tests performed on steel plates are presented. The geometry consisted of circular plates with welded boundary condition penetrated by a conical shaped punch with either a radiused or flat cylindrical end. After initial failure, the conical portion of the punch was driven through the plate to exercise tearing mechanics. Tests were performed quasi-statically with a hydraulic actuator and dynamically using a high-capacity drop table. Deformation and strain were measured with a stereo DIC system. The quasi-static tests utilized a conventional direct-view DIC technique while the dynamic tests required development of an indirect-view technique using a mirror. Experimental details used to conduct the test series will be presented along with test results. Methods of assessing test-to-test repeatability will be discussed. DIC results will also be synchronized and compared with transducer data (displacement and strain).

  6. 46 CFR 32.59-1 - Minimum section modulus and plating thickness requirements-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... I oil cargo listed in 46 CFR Table 30.25-1. (c) For all vessels except those limited on their... SPECIAL EQUIPMENT, MACHINERY, AND HULL REQUIREMENTS Minimum Longitudinal Strength and Plating Thickness... strength plating must be at least as follows: (1) Weather deck: 75 percent of Rule thickness; (2) Hatch:...

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

    PubMed

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

    2002-05-01

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

  8. Microstructure and properties of quenched-and-aged plates produced from a copper-bearing HSLA steel

    SciTech Connect

    Sen, S.K.; Ray, A.; Avtar, R.; Dhua, S.K.; Prasad, M.S.; Jha, P.; Sengupta, P.P.; Jha, S.

    1998-08-01

    For the first time in India, quenched-and-tempered (Q and T) plates of copper-bearing high-strength low-alloy (HSLA) steel have been commercially developed for naval structural applications. A 50 ton production heat was made through electric arc furnace (EAF)-vacuum are degassing (VAD) route and continuously cast into 170 mm thick slabs. These slabs were conditioned, reheated in walking-beam furnace and hot rolled in plate mill into plates of 10 to 16 mm thickness. The as-rolled plates were hardened through oil quenching and subsequently tempered (aged) at 630 C to achieve the combination of high-strength and good low-temperature impact toughness. The microstructures of heat treated plates showed fine acicular ferrite with grain sizes ranging between ASTM No. 9 and 10. From the standpoint of tensile properties, Q and T plates of all thicknesses exhibited significantly higher yield strengths than the minimum stipulated value of 552 MPa for HY-80/HSLA-80 steels. The elongation (22.20 to 26.00%) and reduction in area (62.12 to 67.62%) values achieved also exceeded the respective minimum requirements of 20 and 50% stipulated for such steels. The trend in variation of Charpy V-notch (CVN) impact energies at room temperature, {minus}18, and {minus}62 C not only showed significantly higher values than that stipulated for HY-80 and HSLA-100 steels at {minus}18 C, but also indicated that the CVN impact energies achieved (105.15 to 144.25 J) at {minus}62 C were higher than the estimated value of 90 J for HSLA-80/HSLA-100 steels at this temperature.

  9. Frequency spectra of AT-cut quartz plates with electrodes of unequal thickness.

    PubMed

    Wang, Jining; Hu, Yuantai; Yang, Jiashi

    2010-05-01

    We study vibrations of an AT-cut quartz plate with electrodes of unequal thickness. Mindlin's first-order plate theory is used. Dispersion relations for straight-crested waves in an unbounded plate and frequency spectra of modes in a finite plate are obtained. Results show that, because of the unequal thickness of the electrodes, the two originally uncoupled groups of modes are now coupled. One group consists of thickness-shear, flexure, and face-shear. The other has thickness-twist and extension. This coupling by asymmetric electrodes changes the frequency spectra and affects resonator performance. To avoid the effects of this coupling, a series of discrete values of the length/thickness ratio of the crystal plate need to be excluded. PMID:20442025

  10. [Theoretical analysis and numerical simulation of effect of steel plate positions on steel plate rigidity in internal fixation of bone surgery].

    PubMed

    Chen, Bingzhi; Gu, Yuanxian; Lü, Decheng; Lü, Xuemin

    2003-09-01

    In this study we calculate theoretically and use FEM to simulate the effect of plate position relative to bending direction on the overall bending stiffness of the composite system plate-bone. The results show that for different bending directions the effect of the modulus of elasticity of the plate is negligible. Changing the position of a plate will often alter the stress obviously. During the operation, the steel plate should be assigned onto the tension side of the bone. PMID:14565005

  11. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... § 179.301 and shall be such that at the tank test pressure the maximum fiber stress in the wall of the... psig; s = wall stress in psig (c) If plates are clad with material having tensile strength at...

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

    SciTech Connect

    Wang, H.; Turner, J. A.

    2008-01-01

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

  13. Color Anodizing of Titanium Coated Rolled Carbon Steel Plate

    SciTech Connect

    Sarajan, Zohair; Mobarakeh, Hooman Nikbakht; Namiranian, Sohrab

    2011-12-26

    As an important kind of structural materials, the titanium cladded steel plates have the advantages of both metals and have been applied in aviation, spaceflight, chemical and nuclear industries. In this study, the specimens which were prepared under soldering mechanism during rolling were anodized by electrochemical process under a given conditions. The color anodizing takes place by physical phenomenon of color interference. Part of incident light on the titanium oxide is reflected and the other part reflects inside coated titanium layer. Major part of the light which reflects from titanium-oxide interface, reflects again inside of the oxide layer.

  14. A combined lift and propulsion system of a steel plate by transverse flux linear induction motors

    SciTech Connect

    Hayashiya, H.; Ohsaki, H.; Masada, E.

    1999-09-01

    To realize a non-contacting conveyance of a steel plate, a combined lift and propulsion system of a steel plate by transverse flux linear induction motors (LIMs) is proposed. By introducing the DC biased AC feeding to the LIM< a steel plate is supported stably and efficiently. In this paper, after showing the advantages of the system, the magnetic levitation experiments are carried out to investigate the feasibility of the system.

  15. Impact extractive fracture of jointed steel plates of a bolted joint

    NASA Astrophysics Data System (ADS)

    Daimaruya, M.; Fujiki, H.; Ambarita, H.

    2012-08-01

    This study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of a bolted joint used in a car body. For the accurate prediction of crash characteristics of car bodies by computer-aided engineering (CAE), it is also necessary to examine the behavior and fracture of jointed steel plates subjected to impact loads. Although the actual impact fracture of jointed steel plates of a bolted joint used in cars is complicated, for simplifying the problem it might be classified into the shear fracture and the extractive fracture of jointed steel plates. Attention is given to the extractive fracture of jointed steel plates in this study. The extractive behavior and fracture of three kinds of steel plates used for cars are examined in experiments and numerical simulations. The impact extraction test of steel plates jointed by a bolt is performed using the one-bar method, together with the static test. In order to understand the mechanism of extractive fracture process of jointed steel plates, numerical simulations by a FEM code LS-DYNA are also carried out. The obtained results suggest that a stress-based fracture criterion may be developed for the impact extractive fracture of jointed steel plates of a bolted joint used in a car body.

  16. Strengthening and Toughening of a Heavy Plate Steel for Shipbuilding with Yield Strength of Approximately 690 MPa

    NASA Astrophysics Data System (ADS)

    Liu, Dongsheng; Cheng, Binggui; Chen, Yuanyuan

    2013-01-01

    HSLA-100 steel with high content of alloying elements (nominally in wt pct, 3.5 Ni, 1.6 Cu, and 0.6Mo) is now used to produce heavy plates for constructing a hull and drilling platform. We proposed here a substantially leaner steel composition (containing 1.7 Ni, 1.1 Cu, and 0.5Mo) to produce a heavy plate to 80 mm thickness with mechanical properties comparable with those of the HSLA-100 grade. A continuous cooling transformation (CCT) diagram of the steel was constructed. Key parameters of thermal treatment and revealing mechanisms of strengthening and toughening were derived based on industrial production trials. The microstructures of the 80-mm-thick plate were lath-like bainite (LB) at near surface of the quarter thickness ( t/4), and granular bainite (GB)+LB at center thickness ( t/2) after solutionizing and water quenching (Q). The effect of tempering (T) on the microstructures and properties of the plate was investigated. Excellent combination of room temperature strength and low-temperature Charpy V-notch (CVN) toughness approximately equivalent to that of the HSLA 100 grade (YS > 690 MPa, CVN energy >100 J even at 193 K [-80 °C]) was achieved in the plate treated by the QT process with tempering temperature of 898 K (625 °C). The combination of strength and toughness at t/4 is superior to that at t/2 of the plate under both as-quenched and QT conditions. This result is attributed to that the fraction of high-angle grain boundaries (HAGBs) at t/4 is higher than that at t/2.

  17. General analytical approach for sound transmission loss analysis through a thick metamaterial plate

    SciTech Connect

    Oudich, Mourad; Zhou, Xiaoming; Badreddine Assouar, M.

    2014-11-21

    We report theoretically and numerically on the sound transmission loss performance through a thick plate-type acoustic metamaterial made of spring-mass resonators attached to the surface of a homogeneous elastic plate. Two general analytical approaches based on plane wave expansion were developed to calculate both the sound transmission loss through the metamaterial plate (thick and thin) and its band structure. The first one can be applied to thick plate systems to study the sound transmission for any normal or oblique incident sound pressure. The second approach gives the metamaterial dispersion behavior to describe the vibrational motions of the plate, which helps to understand the physics behind sound radiation through air by the structure. Computed results show that high sound transmission loss up to 72 dB at 2 kHz is reached with a thick metamaterial plate while only 23 dB can be obtained for a simple homogeneous plate with the same thickness. Such plate-type acoustic metamaterial can be a very effective solution for high performance sound insulation and structural vibration shielding in the very low-frequency range.

  18. Ricochet of a tungsten heavy alloy long-rod projectile from deformable steel plates

    NASA Astrophysics Data System (ADS)

    Lee, Woong; Lee, Heon-Joo; Shin, Hyunho

    2002-10-01

    Ricochet of a tungsten heavy alloy long-rod projectile from oblique steel plates with a finite thickness was investigated numerically using a full three-dimensional explicit finite element method. Three distinctive regimes resulting from oblique impact depending on the obliquity, namely simple ricochet, critical ricochet and target perforation, were investigated in detail. Critical ricochet angles were calculated for various impact velocities and strengths of the target plates. It was predicted that critical ricochet angle increases with decreasing impact velocities and that higher ricochet angles were expected if higher strength target materials are employed. Numerical predictions were compared with existing two-dimensional analytical models. Experiments were also carried out and the results supported the predictions of the numerical analysis.

  19. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... psig; S = minimum tensile strength of plate material in p.s.i. as prescribed in § 179.300-7; t... shall be such that at the tank test pressure the maximum fiber stress in the wall of the tank will not... = inside diameter in inches; D = outside diameter in inches; p = tank test pressure in psig; s =...

  20. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... psig; S = minimum tensile strength of plate material in p.s.i. as prescribed in § 179.300-7; t... shall be such that at the tank test pressure the maximum fiber stress in the wall of the tank will not... = inside diameter in inches; D = outside diameter in inches; p = tank test pressure in psig; s =...

  1. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... psig; S = minimum tensile strength of plate material in p.s.i. as prescribed in § 179.300-7; t... shall be such that at the tank test pressure the maximum fiber stress in the wall of the tank will not... = inside diameter in inches; D = outside diameter in inches; p = tank test pressure in psig; s =...

  2. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... psig; S = minimum tensile strength of plate material in p.s.i. as prescribed in § 179.300-7; t... shall be such that at the tank test pressure the maximum fiber stress in the wall of the tank will not... = inside diameter in inches; D = outside diameter in inches; p = tank test pressure in psig; s =...

  3. Ultra fast cooling of hot steel plate by air atomized spray with salt solution

    NASA Astrophysics Data System (ADS)

    Mohapatra, Soumya S.; Ravikumar, Satya V.; Jha, Jay M.; Singh, Akhilendra K.; Bhattacharya, Chandrima; Pal, Surjya K.; Chakraborty, Sudipto

    2014-05-01

    In the present study, the applicability of air atomized spray with the salt added water has been studied for ultra fast cooling (UFC) of a 6 mm thick AISI-304 hot steel plate. The investigation includes the effect of salt (NaCl and MgSO4) concentration and spray mass flux on the cooling rate. The initial temperature of the steel plate before the commencement of cooling is kept at 900 °C or above, which is usually observed as the "finish rolling temperature" in the hot strip mill of a steel plant. The heat transfer analysis shows that air atomized spray with the MgSO4 salt produces 1.5 times higher cooling rate than atomized spray with the pure water, whereas air atomized spray with NaCl produces only 1.2 times higher cooling rate. In transition boiling regime, the salt deposition occurs which causes enhancement in heat transfer rate by conduction. Moreover, surface tension is the governing parameter behind the vapour film instability and this length scale increases with increase in surface tension of coolant. Overall, the achieved cooling rates produced by both types of salt added air atomized spray are found to be in the UFC regime.

  4. 75 FR 29519 - Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China: Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    ... International Trade Administration Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China... antidumping duty order on certain cut-to-length carbon steel plate (``CTL Plate'') from the People's Republic of China (``PRC''). See Suspension Agreement on Certain Cut- to-Length Carbon Steel Plate From...

  5. 76 FR 24462 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... International Trade Administration Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China... antidumping duty order on certain cut-to-length carbon steel plate (``CTL Plate'') from the People's Republic of China (``PRC''). See Suspension Agreement on Certain Cut- to-Length Carbon Steel Plate From...

  6. Linear and non-linear deflection analysis of thick rectangular plates. 2: Numerical applications

    NASA Astrophysics Data System (ADS)

    Bencharif, N.; Ng, S. F.

    1994-03-01

    Variational methods are widely used for the solution of complex differential equations in mechanics for which exact solutions are not possible. The finite difference method, although well known as an efficient numerical method, was applied in the past only for the analysis of linear and non-linear thin plates. In this paper the suitability of the method for the analysis of non-linear deflection of thick plates is studied for the first time. While there are major differences between small deflection and large deflection plate theories, the former can be treated as a particular case of the latter, when the centre deflection of the plate is less than or equal to 0.2-0.25 of the thickness of the plate. The finite difference method as applied here is a modified finite difference approach to the ordinary finite difference method generally used for the solution of thin plate problems. In this analysis thin plates are treated as a particular case of the corresponding thick plate when the boundary conditions of the plates are taken into account. The method is first applied to investigate the deflection behaviour of clamped and simply supported square isotropic thick plates. After the validity of the method is established, it is then extended to the solution of rectangular thick plates of various aspect ratios and thicknesses. Generally, beginning with the use of a limited number of mesh sizes for a given plate aspect ratio and boundary conditions, a general solution of the problem including the investigation of accuracy and convergence was extended to rectangular thick plates by providing more detailed functions satisfying the rectangular mesh sizes generated automatically by the program. Whenever possible results obtained by the present method are compared with existing solutions in the technical literature obtained by much more laborious methods and close agreements are found. The significant number of results presented here are not currently available in the technical

  7. A solution procedure for behavior of thick plates on a nonlinear foundation and postbuckling behavior of long plates

    NASA Technical Reports Server (NTRS)

    Stein, M.; Stein, P. A.

    1978-01-01

    Approximate solutions for three nonlinear orthotropic plate problems are presented: (1) a thick plate attached to a pad having nonlinear material properties which, in turn, is attached to a substructure which is then deformed; (2) a long plate loaded in inplane longitudinal compression beyond its buckling load; and (3) a long plate loaded in inplane shear beyond its buckling load. For all three problems, the two dimensional plate equations are reduced to one dimensional equations in the y-direction by using a one dimensional trigonometric approximation in the x-direction. Each problem uses different trigonometric terms. Solutions are obtained using an existing algorithm for simultaneous, first order, nonlinear, ordinary differential equations subject to two point boundary conditions. Ordinary differential equations are derived to determine the variable coefficients of the trigonometric terms.

  8. License plate cosmetic corrosion test of automotive coated steel sheet

    SciTech Connect

    Townsend, H.E.; Simpson, M.W.; McCune, D.C.

    1999-04-01

    A new standard laboratory test (SAE J2334) for evaluation of the cosmetic corrosion resistance of autobody steel sheet has been developed through the joint efforts of the Society of Automotive Engineers Automotive Corrosion Prevention Committee (SAE/ACAP) and the Auto/Steel Partnership (A/SP) Corrosion Task Force. Results from this test gave an excellent correlation with those of on-vehicle tests conducted for 5 years in Canada at St. John`s, Newfoundland, and Montreal, Quebec. To determine how results of the Canadian tests related to environments in the United States, racks of identical materials were mounted on the front license plate brackets of cars driven in various locations in the US snowbelt, including Bethlehem, Pennsylvania; Detroit, Michigan, and Chardon, Ohio. After 4 years to 5 years, these tests showed the US environments produced less scribe creep and more red rust than those conducted in Canada. Similar rankings were obtained for the scribe creep resistance of the various coated steel sheet products when compared at equivalent amounts of corrosion. However, the ranking of materials changed at longer exposure times in Canada, and for that reason, it was concluded that the 5-year Canadian results used in the development of the SAE J2334 test provided a better real-world performance standard.

  9. The displacement field in the vibration analysis of laminated thick plates

    SciTech Connect

    Ohta, Yoshiki; Narita, Yoshihiro

    1995-11-01

    The present paper discusses the assumption of displacement fields used in the vibration analysis of FRP laminated thick plates. For this purpose, the strain and kinetic energies of a FRP cross-ply laminated plate are evaluated analytically based on the three-dimensional theory of elasticity, and the displacements of the rectangular plate, which are simply-supported at all edges, are expanded into the polynomial forms with respect to thickness coordinate. A frequency equation is formulated by using the energy method minimizing the Lagrange function. In the numerical calculations, natural frequencies are obtained for the plates with various stacking sequence and the thickness ratios, and the validity of the assumption of displacement fields and the range of applicability of the various plate theories (e.g. the Classical Plate Theory (CPT), the First-Order Shear Deformation Theory (FSDT) and the Higher-Order Shear Deformation Theory (HSDT)), which are widely used in the vibration analysis of FRP laminated plates, to the laminated thick plates are discussed by comparing the present results with the CPT and the FSDT solutions.

  10. Oscillating layer thickness and vortices generated in oscillation of finite plate

    NASA Astrophysics Data System (ADS)

    Sin, V. K.; Wong, I. K.

    2016-06-01

    Moving mesh strategy is used in the model of flow induced by oscillating finite plate through software - COMSOL Multiphysics. Flow is assumed to be laminar and arbitrary Lagrangian-Eulerian method is used for moving mesh in the simulation. Oscillating layer thickness is found which is different from the analytical solution by 2 to 3 times depends on the oscillating frequency. Vortices are also observed near the oscillating finite plate because of the edge effect of the finite plate.

  11. Laser-Assisted Stir Welding of 25-mm-Thick HSLA-65 Plate

    NASA Astrophysics Data System (ADS)

    Williamson, Keith M.

    2002-12-01

    Laser-assisted stir welding is a hybrid process that combines energy from a laser with functional heating and mechanical energy to join materials in the solid state. The technology is an adaptation of friction stir welding which is particularly suited for joining thick plates. Aluminum plates up to 75 mm thick have been successfully joined using friction stir welding. Since joining occurs in the solid state, stir technology offers the capability for fabricating full penetration joints in thick plates with better mechanical properties and less weld distortion than is possible by fusion processes. Currently friction stir welding is being used in several industries to improve productivity, reduce weight, and increase the strength of welded structures. Examples include: (a) the aircraft/aerospace industry where stir technology is currently being used to fabricate the space shuttle's external tank as well as components of the Delta family of rockets; (b) the shipping industry where container manufacturers are using stir technology to produce lighter containers with more payload capacity; and (c) the oil industry where offshore platform manufactures are using automated stir welding plants to fabricate large panels and structures up to 16 meters long with widths as required. In all these cases, stir technology has been restricted to aluminum alloys; however, stainless and HSLA 65 steels have been recently stir welded with friction as the primary heat source. One of the difficulties in adapting stir welding to steel is tool wear aggravated by the high tool rubbing velocities needed to provide frictional heat input into the material. Early work showed that the tool shoulder reached temperatures above 1000 C and the weld seam behind the tool stayed within this temperature range for up to 25 mm behind the tool. Cross sections of stir welded samples showed that the heat-affected zone is relatively wide and follows the profile of the tool shoulder. Besides minimizing the tool

  12. 76 FR 31588 - Stainless Steel Plate in Coils From Belgium: Rescission of Countervailing Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

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

  13. 75 FR 64709 - Stainless Steel Plate in Coils From Belgium: Notice of Rescission of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

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

  14. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  15. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  16. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  17. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  18. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  19. 78 FR 31577 - Diffusion-Annealed, Nickel-Plated Flat-Rolled Steel Products From Japan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-24

    ... Commission, Washington, DC, and by publishing the notice in the Federal Register of April 2, 2013 (78 FR... COMMISSION Diffusion-Annealed, Nickel-Plated Flat-Rolled Steel Products From Japan Determination On the basis... injured by reason of imports from Japan of diffusion-annealed, nickel-plated flat-rolled steel...

  20. Response of a circular steel plate with different weld geometries subject to impact loading

    NASA Astrophysics Data System (ADS)

    Abdel-Malek, S.; Meyer, L. W.; Herzig, N.

    2012-08-01

    The dynamic response of clamped circular steel plates was experimentally investigated under impact loading. The experiments were performed using a high energy drop weight machine with a 5 ton drop weight, which falls from a height of 0.8 m and results in a total impact energy of 40 kJ. Target plates of 10 mm thickness and 580 mm diameter were welded in three different geometrical configurations of weld elements on the lower side. The impact process was carried out using a hemispherical punch. The force was registered by strain gages on the punch. A full dynamic strain field measurement was applied on the tension side using two high speed cameras. The evaluation of the strain field was carried out with the speckle photography technique. The effect of cracks and welding on the deformation and failure behavior was studied using pre-cracked disks and plates with welded webs, welded circular discs and also with a weld seam only. The failure of the plates was registered using the high speed cameras and from the force signal. The results are analyzed and discussed regarding the behavior of the material and component under high rate loading.

  1. A refined higher-order theory and its finite element method for thick laminated plates

    NASA Astrophysics Data System (ADS)

    Fu, Xiaohua; Chen, Haoran; Wang, Zhenming

    1992-04-01

    An improved higher-order theory developed to enhance the accuracy of the shear deformation theory of thick laminated plates is presented. The Legendre polynomials are introduced in the approximate displacement distributions across the plate thickness, and an FEM is suggested from the original equations. The accuracy of the present theory is examined by applying it to bending problems of laminate plates solved by Pagano. The results are compared with 3D elasticity solutions, the second order shear deformation theory, and some other higher-order shear deformation theory solutions. The present theory shows the deflections and stress more accurately than that obtained from previous works in the structural analysis of laminated plates with a small span with respect to thickness.

  2. XDT in HTPB propellant from steel flyer plate impact tests

    NASA Astrophysics Data System (ADS)

    Tanaka, Katsumi; Noda, Keiichiro; Hyodo, Yukio; Nakamura, Hiroyuki; Kosaka, Katsuaki; Nakayama, Takashi; Katayama, Masahide; Takeba, Atsushi

    2000-04-01

    Several experiments simulating ground impact explosion following the command destruction of a launch vehicle have been performed using HTPB propellant samples of mass 460 to 940 kg impacted by a steel flyer plate. Impact velocities were varied from 135 m/s to 170 m/s. Strong explosions were observed at impact velocities higher than 150 m/s for tests of solid rocket propellant weighting 460 kg. The XDT (Unknown to Detonation Transition) is studied using a bulk failure reaction model including strain rate effect. Computational results are compared with observed blast waves for various impact velocities. The present model has been successfully applied to 22 inch Critical Diameter tests for SRMU HTPB propellant.

  3. Vibration and damping of laminated, composite-material plates including thickness-shear effects

    NASA Technical Reports Server (NTRS)

    Bert, C. W.; Siu, C. C.

    1972-01-01

    An analytical investigation of sinusoidally forced vibration of laminated, anisotropic plates including bending-stretching coupling, thickness-shear flexibility, all three types of inertia effects, and material damping is presented. In the analysis the effects of thickness-shear deformation are considered by the use of a shear correction factor K, analogous to that used by Mindlin for homogeneous plates. Two entirely different approaches for calculating the thickness-shear factor for a laminate are presented. Numerical examples indicate that the value of K depends on the layer properties and the stacking sequence of the laminate.

  4. Understanding the antimicrobial activity behind thin- and thick-rolled copper plates.

    PubMed

    Yousuf, Basit; Ahire, Jayesh J; Dicks, Leon M T

    2016-06-01

    The aim of this study was to compare the antibacterial properties of the surfaces of copper plates that were rolled to a thickness of 25 and 100 μm. Differences in topology of 25- and 100-μm-thick copper plates were studied using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). Antibacterial activity of the copper surfaces was tested against strains of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Listeria monocytogenes, Salmonella typhimurium, Streptococcus sp. BY1, Enterococcus sp. BY2, and Bacillus cereus BY3. Changes in viable cell numbers were determined by plating onto optimal growth media and staining with LIVE/DEAD BacLight™. Changes in metabolic activity were recorded by expression of the luciferase (lux) gene. Cell morphology was studied using SEM. Accumulation and diffusion of copper from cells were recorded using inductively coupled plasma mass spectroscopy (ICP-MS). Lipid and protein oxidation were recorded spectrophotometrically. Surfaces of 25-μm-thick copper plates were rough compared to that of 100-μm-thick copper plates. For most species, a five-log reduction in cell numbers, cell membrane instability, and a decline in metabolic activity were recorded after 15 min of exposure to 25-μm-thick copper plates. Copper accumulated in the cells, and lipids and proteins were oxidized. The rough surface of thinner copper plates (25 μm thick) released more copper and was more antimicrobial compared to thicker (100 μm) copper plates. Cell death was attributed to destabilization of the cell membrane, lipid peroxidation, and protein oxidation. PMID:26860943

  5. The Relationship Between Microstructural Evolution and Mechanical Properties of Heavy Plate of Low-Mn Steel During Ultra Fast Cooling

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Wang, Zhao-dong; Wang, Bing-xing; Wang, Guo-dong; Misra, R. D. K.

    2015-07-01

    We describe here the electron microscopy and mechanical property studies that were conducted in an industrially processed 20- and 40-mm C-Mn thick plates that involved a new approach of ultrafast cooling (UFC) together with significant reduction in Mn-content of the steel by ~0.3 to 0.5 pct, in relation to the conventional C-Mn steels, with the aim of cost-effectiveness. The study demonstrated that nanoscale cementite precipitation occurred during austenite transformation in the matrix of heavy plate during UFC, providing significant precipitation strengthening. With decrease in UFC stop temperature and consequent increase in the degree of undercooling, there was a transition in the morphology of cementite from lamellar to irregular-shaped nanoscale particles in the 20 mm heavy plate. With the increase in plate thickness, nanoscale cementite precipitated in bainitic lath at the surface of 40 mm heavy plate, which significantly increased the strength and decreased the elongation. Simultaneously, microstructural evolution in hot-rolled sheets was studied via simulation experiments using laboratory rolling mill to define the limits of microstructural evolution that can obtained in the UFC process and develop an understanding of the evolved microstructure in terms of process parameters.

  6. 46 CFR 54.25-3 - Steel plates (modifies UCS-6).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...; see 46 CFR 54.01-1) will be allowed only in Class III pressure vessels (see Table 54.01-5(b)). ... 46 Shipping 2 2011-10-01 2011-10-01 false Steel plates (modifies UCS-6). 54.25-3 Section 54.25-3... Construction With Carbon, Alloy, and Heat Treated Steels § 54.25-3 Steel plates (modifies UCS-6). The...

  7. 46 CFR 54.25-3 - Steel plates (modifies UCS-6).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...; see 46 CFR 54.01-1) will be allowed only in Class III pressure vessels (see Table 54.01-5(b)). ... 46 Shipping 2 2012-10-01 2012-10-01 false Steel plates (modifies UCS-6). 54.25-3 Section 54.25-3... Construction With Carbon, Alloy, and Heat Treated Steels § 54.25-3 Steel plates (modifies UCS-6). The...

  8. 46 CFR 54.25-3 - Steel plates (modifies UCS-6).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...; see 46 CFR 54.01-1) will be allowed only in Class III pressure vessels (see table 54.01-5(b)). ... 46 Shipping 2 2013-10-01 2013-10-01 false Steel plates (modifies UCS-6). 54.25-3 Section 54.25-3... Construction With Carbon, Alloy, and Heat Treated Steels § 54.25-3 Steel plates (modifies UCS-6). The...

  9. 46 CFR 54.25-3 - Steel plates (modifies UCS-6).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...; see 46 CFR 54.01-1) will be allowed only in Class III pressure vessels (see Table 54.01-5(b)). ... 46 Shipping 2 2010-10-01 2010-10-01 false Steel plates (modifies UCS-6). 54.25-3 Section 54.25-3... Construction With Carbon, Alloy, and Heat Treated Steels § 54.25-3 Steel plates (modifies UCS-6). The...

  10. 46 CFR 54.25-3 - Steel plates (modifies UCS-6).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...; see 46 CFR 54.01-1) will be allowed only in Class III pressure vessels (see table 54.01-5(b)). ... 46 Shipping 2 2014-10-01 2014-10-01 false Steel plates (modifies UCS-6). 54.25-3 Section 54.25-3... Construction With Carbon, Alloy, and Heat Treated Steels § 54.25-3 Steel plates (modifies UCS-6). The...

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

    SciTech Connect

    1998-11-01

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

  12. Shear fracture of jointed steel plates of bolted joints under impact load

    NASA Astrophysics Data System (ADS)

    Daimaruya, M.; Fujiki, H.; Ambarita, H.; Kobayashi, H.; Shin, H.-S.

    2013-07-01

    The present study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of bolted joints used in a car body, which contributes to crash simulations by CAE. We focus our attention on the shear fracture of the jointed steel plates of lap-bolted joints in the suspension of a car under impact load. Members of lap-bolted joints are modelled as a pair of steel plates connected by a bolt. One of the plates is a specimen subjected to plastic deformation and fracture and the other is a jig subjected to elastic deformation only. Three kinds of steel plate specimens are examined, i.e., a common steel plate with a tensile strength of 270 MPa and high tensile strength steel plates of 440 and 590 MPa used for cars. The impact shear test was performed using the split Hopkinson bar technique for tension impact, together with the static test using a universal testing machine INSTRON 5586. The behaviour of the shear stress and deformation up to rupture taking place in the joint was discussed. The obtained results suggest that a stress-based fracture criterion may be developed for the impact fracture of jointed steel plates of a lap-bolted joint.

  13. Damage assessment and residual compression strength of thick composite plates with through-the-thickness reinforcements

    NASA Technical Reports Server (NTRS)

    Smith, Barry T.; Farley, Gary L.; Maiden, Janice; Coogan, Dreux; Moore, Judith G.

    1991-01-01

    Damage in composite materials was studied with through-the-thickness reinforcements. As a first step it was necessary to develop new ultrasonic imaging technology to better assess internal damage of the composite. A useful ultrasonic imaging technique was successfully developed to assess the internal damage of composite panels. The ultrasonic technique accurately determines the size of the internal damage. It was found that the ultrasonic imaging technique was better able to assess the damage in composite panel with through-the-thickness reinforcements than by destructively sectioning the specimen and visual inspection under a microscope. Five composite compression-after-impact panels were tested. The compression-after-impact strength of the panels with the through-the-thickness reinforcements was almost twice that of the comparable panel without through-the-thickness reinforcement.

  14. Damage assessment and residual compression strength of thick composite plates with through-the-thickness reinforcements

    NASA Technical Reports Server (NTRS)

    Smith, Barry T.

    1990-01-01

    Damage in composite materials was studied with through-the-thickness reinforcements. As a first step it was necessary to develop new ultrasonic imaging technology to better assess internal damage of the composite. A useful ultrasonic imaging technique was successfully developed to assess the internal damage of composite panels. The ultrasonic technique accurately determines the size of the internal damage. It was found that the ultrasonic imaging technique was better able to assess the damage in a composite panel with through-the-thickness reinforcements than by destructively sectioning the specimen and visual inspection under a microscope. Five composite compression-after-impact panels were tested. The compression-after-impact strength of the panels with the through-the-thickness reinforcements was almost twice that of the comparable panel without through-the-thickness reinforcement.

  15. Experimental study of the effect of spray inclination on ultrafast cooling of a hot steel plate

    NASA Astrophysics Data System (ADS)

    Ravikumar, Satya V.; Jha, Jay M.; Mohapatra, Soumya S.; Sinha, Apurva; Pal, Surjya K.; Chakraborty, Sudipto

    2013-10-01

    The ultrafast cooling that occurs during high mass flux air-atomized spray impingement on a hot 6 mm thick stainless steel plate has been studied experimentally in terms of the nozzle inclination between 0° and 60°. The average mass flux of water used in the study accounts to 510 kg/m2 s. The coolants used in the study are pure water and surfactant water of 600 ppm concentration. The initial temperature of the plate has been maintained at 900 °C, which is the temperature of a hot strip on run-out table in steel industry. The transient surface heat flux and temperature histories have been estimated by an inverse heat solver using measured temperature input data. Heat transfer results demonstrates that optimum cooling efficiency (~2.76 MW/m2, 194 °C/s) for pure water has been achieved at 30° nozzle orientation. The inclined nozzle has not been found beneficial when surfactant water is used as the coolant.

  16. Experimental and Numerical Investigation on the Ballistic Resistance of Double-Layered Steel Plates

    NASA Astrophysics Data System (ADS)

    Xiao, Xinke; Zhang, Wei; Guo, Zitao; Wei, Gang

    2011-06-01

    The ballistic perforation resistance of double-layered steel plates impacted by flat-nosed projectiles was investigated both experimentally and numerically. In the tests, 10 mm thick (intact or spaced by 200 mm gap space) targets of Q235A steel were impacted using a gas-gun at sub-ordnance velocity, and the ballistic limit velocity of the different target configurations was obtained. The Johnson-Cook strength and fracture models were used in the finite element simulations, where the model constants were calibrated by preliminary material tests and taken from open literature. In general, good agreement was obtained between the numerical simulations and the experimental results. It was found that the ballistic resistance of spaced targets suffers from large divergence due to the projectile's different residual attitude after perforation of the front plate, and that it seems the initial-residual velocity data yield to two groups and therefore give birth to two ballistic limit velocities. However, the overall ballistic resistance of the spaced targets is less than that of the in contact ones.

  17. 77 FR 73013 - Stainless Steel Plate in Coils From Belgium: Antidumping Duty Administrative Review, 2010-2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-07

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

  18. Propagating plane harmonic waves through finite length plates of variable thickness using finite element techniques

    NASA Technical Reports Server (NTRS)

    Clark, J. H.; Kalinowski, A. J.; Wagner, C. A.

    1983-01-01

    An analysis is given using finite element techniques which addresses the propagaton of a uniform incident pressure wave through a finite diameter axisymmetric tapered plate immersed in a fluid. The approach utilized in developing a finite element solution to this problem is based upon a technique for axisymmetric fluid structure interaction problems. The problem addressed is that of a 10 inch diameter axisymmetric fixed plate totally immersed in a fluid. The plate increases in thickness from approximately 0.01 inches thick at the center to 0.421 inches thick at a radius of 5 inches. Against each face of the tapered plate a cylindrical fluid volume was represented extending five wavelengths off the plate in the axial direction. The outer boundary of the fluid and plate regions were represented as a rigid encasement cylinder as was nearly the case in the physical problem. The primary objective of the analysis is to determine the form of the transmitted pressure distribution on the downstream side of the plate.

  19. Thickness effects on the plastic collapse of perforated plates with triangular penetration patterns

    SciTech Connect

    Gordon, J.L.; Jones, D.P.; Holliday, J.E.

    2000-03-01

    This paper investigates the effects of plate thickness on the accuracy of limit load solutions obtained using an elastic-perfectly plastic [EPP] equivalent solid [EQS] procedure for flat perforated plates with a triangular array of penetrations. The EQS approach for limit loads is based on an EQS collapse surface that is valid for generalized plane strain. This assumption is applicable for very thick plates but is known to be less reasonable for very thin plates where plane stress may be a better assumption. The limits of applicability of the generalized plane strain assumption are investigated by obtaining limit load solutions for perforated plates of various thicknesses that are subjected to in-plane and bending loads. Plastic limit load solutions obtained using three-dimensional EPP finite element analysis [FEA] of models which include each penetration explicitly are compared with solutions obtained using the EQS approximation. The penetration pattern chosen for this study has a ligament efficiency (ligament width-to-pitch ratio, h/P) of 0.32. For plates thicker than the pitch, the limit load calculated using the EQS method for both in-plane and bending loads is shown to be very accurate (within 4%) of the limit load calculated for the explicit model. On the other hand, for thin plates (t/P< 2), the EQS limit load is 5% greater than the explicit limit load for bending and 8% greater than the explicit limit load for in-plane loads. For thinner plates, the collapse surface is tied to the local geometry deformation and, hence, an equivalent solid plate representation of plastic collapse is a function of deformation mode and thickness.

  20. 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.

  1. New-type steel plate with ultra high crack-arrestability

    SciTech Connect

    Ishikawa, T.; Nomiyama, Y.; Hagiwara, Y.; Yoshikawa, H.; Oshita, S.; Mabuchi, H.

    1995-12-31

    A new-type steel plate has been developed by controlling the microstructure of the surface layers. The surface layer consists of ultra fine grain ferrite microstructure, which provides excellent fracture toughness even at cryogenic temperature. When an unstable brittle crack propagates in the developed steel plate, shear-lips can be easily formed due to the surface layers with ultra fine grain microstructure. Since unstable running crack behavior is strongly affected by side-ligaments (shear-lips), which are associated with extensive plastic deformation, enhanced formation of the shear-lips can improve crack arrestability. This paper describes the developed steel plates of HT500MPa tensile strength class for shipbuilding use. Fracture mechanics investigations using large-scale fracture testings (including ultrawide duplex ESSO tests) clarified that the developed steel plates have ultra high crack-arrestability. It was also confirmed that the plates possess sufficient properties, including weldability and workability, for ship building use.

  2. Magnetic levitation of a flexible steel plate with a vibration suppressing magnet

    SciTech Connect

    Hayashiya, H.; Araki, N.; Paddison, J.E.; Ohsaki, H.; Masada, E.

    1996-09-01

    In the steel making process, the application of a magnetic levitation to the steel plate conveyance is expected. The advantages brought by introducing contactless support of a steel plate are improved quality of products, reduced maintenance cost of installations, increased productivity, and quieter operation. Here, a magnetic levitation system that has a vibration suppressing electromagnet which use only the velocity of the levitated object for the control has been studied. The proposed system has advantages of the stale levitation of a flexible steel plate which moves with time under the fixed electromagnets. The simulation of levitated plate`s response using finite element method and the magnetic levitation experiments using such a vibration suppressing magnet were carried out. The results show the vibration suppressing magnet is able to control the low frequency natural vibration effectively, and a notch filter is able to avoid the excitation of the high frequency natural vibration.

  3. Effect of confining pressure due to external jacket of steel plate or shape memory alloy wire on bond behavior between concrete and steel reinforcing bars.

    PubMed

    Choi, Eunsoo; Kim, Dongkyun; Park, Kyoungsoo

    2014-12-01

    For external jackets of reinforced concrete columns, shape memory alloy (SMA) wires are easy to install, and they provide active and passive confining pressure; steel plates, on the other hand, only provide passive confining pressure, and their installation on concrete is not convenient because of the requirement of a special device. To investigate how SMA wires distinctly impact bond behavior compared with steel plates, this study conducted push-out bond tests of steel reinforcing bars embedded in concrete confined by SMA wires or steel plates. For this purpose, concrete cylinders were prepared with dimensions of 100 mm x 200 mm, and D-22 reinforcing bars were embedded at the center of the concrete cylinders. External jackets of 1.0 mm and 1.5 mm thickness steel plates were used to wrap the concrete cylinders. Additionally, NiTiNb SMA wire with a diameter of 1.0 mm was wound around the concrete cylinders. Slip of the reinforcing bars due to pushing force was measured by using a displacement transducer, while the circumferential deformation of specimens was obtained by using an extensometer. The circumferential deformation was used to calculate the circumferential strains of the specimens. This study assessed the radial confining pressure due to the external jackets on the reinforcing bars at bond strength from bond stress-slip curves and bond stress-circumferential strain curves. Then, the effects of the radial confining pressure on the bond behavior of concrete are investigated, and an equation is suggested to estimate bond strength using the radial confining pressure. Finally, this study focused on how active confining pressure due to recovery stress of the SMA wires influences bond behavior. PMID:25971115

  4. A study on friction stir welding of 12mm thick aluminum alloy plates

    NASA Astrophysics Data System (ADS)

    Kumar, Deepati Anil; Biswas, Pankaj; Tikader, Sujoy; Mahapatra, M. M.; Mandal, N. R.

    2013-12-01

    Most of the investigations regarding friction stir welding (FSW) of aluminum alloy plates have been limited to about 5 to 6 mm thick plates. In prior work conducted the various aspects concerning the process parameters and the FSW tool geometry were studied utilizing friction stir welding of 12 mm thick commercial grade aluminum alloy. Two different simple-to-manufacture tool geometries were used. The effect of varying welding parameters and dwell time of FSW tool on mechanical properties and weld quality was examined. It was observed that in order to achieve a defect free welding on such thick aluminum alloy plates, tool having trapezoidal pin geometry was suitable. Adequate tensile strength and ductility can be achieved utilizing a combination of high tool rotational speed of about 2000 r/min and low speed of welding around 28 mm/min. At very low and high dwell time the ductility of welded joints are reduced significantly.

  5. Detecting the thickness mode frequency in a concrete plate using backward wave propagation.

    PubMed

    Bjurström, Henrik; Ryden, Nils

    2016-02-01

    Material stiffness and plate thickness are the two key parameters when performing quality assurance/quality control on pavement structures. In order to estimate the plate thickness non-destructively, the Impact Echo (IE) method can be utilized to extract the thickness resonance frequency. An alternative to IE for estimating the thickness resonance frequency of a concrete plate, and to subsequently enable thickness determination, is presented in this paper. The thickness resonance is often revealed as a sharp peak in the frequency spectrum when contact receivers are used in seismic testing. Due to a low signal-to-noise ratio, IE is not ideal when using non-contact microphone receivers. In studying the complex Lamb wave dispersion curves at a frequency infinitesimally higher than the thickness frequency, it is seen that two counter-directed waves occur at the same frequency but with phase velocities in opposite directions. Results show that it is possible to detect the wave traveling with a negative phase velocity using both accelerometers and air-coupled microphones as receivers. This alternative technique can possibly be used in non-contact scanning measurements based on air-coupled microphones. PMID:26936549

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

    SciTech Connect

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

    1995-11-01

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

  7. Simultaneous measurement of refractive index and thickness of birefringent wave plates.

    PubMed

    Yeh, Yen-Liang

    2008-04-01

    A nondestructive measurement system based on a position sensing detector (PSD) and a laser interferometer for determining the thickness and refractive indices of birefringent optical wave plates has been developed. Unlike previous methods presented in the literature, the proposed metrology system allows the refractive index and thickness properties of the optical plate to be measured simultaneously. The experimental results obtained for the e-light and o-light refractive indices of a commercially available birefringent optical wave plate with refractive indices of n(o)=1.542972 and n(e)=1.552033 are found to be accurate to within 0.004132 and 0.000229, respectively. Furthermore, the experimentally derived value of the wave plate thickness deviates by no more than 0.9 microm from the analytically derived value of 453.95 microm. Overall, the experimental results confirm that the proposed metrology system provides a simple yet highly accurate means of obtaining simultaneous measurements of the refractive indices and thickness of birefringent optical wave plates. PMID:18382573

  8. Crack-growth behavior in thick welded plates of Inconel 718 at room and cryogenic temperatures

    NASA Technical Reports Server (NTRS)

    Forman, R. G.

    1974-01-01

    Results of mechanical-properties and axial-load fatigue and fracture tests performed on thick welded plates of Inconel 718 superalloy are presented. The test objectives were to determine the tensile strength properties and the crack-growth behavior in electron-beam, plasma-arc, and gas tungsten are welds for plates 1.90 cm (0.75 in) thick. Base-metal specimens were also tested to determine the flaw-growth behavior. The tests were performed in room-temperature-air and liquid nitrogen environments. The experimental crack-growth-rate data are correlated with theoretical crack-growth-rate predictions for semielliptical surface flaws.

  9. Measurement of optical thickness variation of BK7 plate by wavelength tuning interferometry.

    PubMed

    Kim, Yangjin; Hibino, Kenichi; Sugita, Naohiko; Mitsuishi, Mamoru

    2015-08-24

    This paper presents the derivation of a 17-sample phase-shifting algorithm that can compensate the miscalibration and first-order nonlinearity of phase shift error, coupling error, and bias modulation of the intensity and satisfy the fringe contrast maximum condition. The phase error of measurements performed using the 17-sample algorithm is discussed and compared with those of measurements obtained using other algorithms. Finally, the optical thickness variation of a BK7 optically transparent plate obtained using a wavelength tuning Fizeau interferometer and the 17-sample algorithm are presented. The experimental results indicate that the optical thickness variation measurement accuracy for the BK7 plate was 3 nm. PMID:26368260

  10. High-accuracy thickness measurement of a transparent plate with the heterodyne central fringe identification technique

    SciTech Connect

    Wu, Wang-Tsung; Hsieh, Hung-Chih; Chang, Wei-Yao; Chen, Yen-Liang; Su, Der-Chin

    2011-07-20

    In a modified Twyman-Green interferometer, the optical path variation is measured with the heterodyne central fringe identification technique, as the light beam is focused by a displaced microscopic objective on the front/rear surface of the test transparent plate. The optical path length variation is then measured similarly after the test plate is removed. The geometrical thickness of the test plate can be calculated under the consideration of dispersion effect. This method has a wide measurable range and a high accuracy in the measurable range.

  11. Effective elastic thickness of the Arabian plate: Weak shield versus strong platform

    NASA Astrophysics Data System (ADS)

    Chen, Bo; Kaban, Mikhail K.; El Khrepy, Sami; Al-Arifi, Nassir

    2015-05-01

    The fan wavelet method has been employed to calculate high-resolution maps of variations of the effective elastic thickness (EET) for the Arabian plate and surroundings. As the initial data, we use high-resolution gravity field, topography, and recent models of sedimentary basins. The western part of the plate is generally characterized by low to midvalues of EET (10-30 km) while the eastern one by high values (50 km and more in the core). This finding confirms that the pronounced asymmetry of the plate is rather associated with fundamental structural differences of the lithosphere than with a forced tilt of the plate due to the rifting in the west-southwest and subduction in the northeast. Therefore, the high topography in the western part of the plate is likely supported by relatively hot mantle that is also responsible for the decrease of EET. These results are generally in agreement with recent seismic tomography models.

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

    SciTech Connect

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

    1994-06-01

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

  13. On the relations between cratonic lithosphere thickness, plate motions, and basal drag

    USGS Publications Warehouse

    Artemieva, I.M.; Mooney, W.D.

    2002-01-01

    An overview of seismic, thermal, and petrological evidence on the structure of Precambrian lithosphere suggests that its local maximum thickness is highly variable (140-350 km), with a bimodal distribution for Archean cratons (200-220 km and 300-350 km). We discuss the origin of such large differences in lithospheric thickness, and propose that the lithospheric base can have large depth variations over short distances. The topography of Bryce Canyon (western USA) is proposed as an inverted analog of the base of the lithosphere. The horizontal and vertical dimensions of Archean cratons are strongly correlated: larger cratons have thicker lithosphere. Analysis of the bimodal distribution of lithospheric thickness in Archean cratons shows that the "critical" surface area for cratons to have thick (>300 km) keels is >6-8 ?? 106 km2 . Extrapolation of the linear trend between Archean lithospheric thickness and cratonic area to zero area yields a thickness of 180 km. This implies that the reworking of Archean crust should be accompanied by thinning and reworking of the entire lithospheric column to a thickness of 180 km in accord with thickness estimates for Proterozoic lithosphere. Likewise, extrapolation of the same trend to the size equal to the total area of all Archean cratons implies that the lithospheric thickness of a hypothesized early Archean supercontinent could have been 350-450 km decreasing to 280-400 km for Gondwanaland. We evaluate the basal drag model as a possible mechanism that may thin the cratonic lithosphere. Inverse correlations are found between lithospheric thickness and (a) fractional subduction length and (b) the effective ridge length. In agreement with theoretical predictions, lithospheric thickness of Archean keels is proportional to the square root of the ratio of the craton length (along the direction of plate motion) to the plate velocity. Large cratons with thick keels and low plate velocities are less eroded by basal drag than small

  14. An ultrasonic method for determination of elastic moduli, density, attenuation and thickness of a polymer coating on a stiff plate.

    PubMed

    Lavrentyev, A I; Rokhlin, S I

    2001-04-01

    An ultrasonic method proposed by us for determination of the complete set of acoustical and geometrical properties of a thin isotropic layer between semispaces (J. Acoust. Soc. Am. 102 (1997) 3467) is extended to determination of the properties of a coating on a thin plate. The method allows simultaneous determination of the coating thickness, density, elastic moduli and attenuation (longitudinal and shear) from normal and oblique incidence reflection (transmission) frequency spectra. Reflection (transmission) from the coated plate is represented as a function of six nondimensional parameters of the coating which are determined from two experimentally measured spectra: one at normal and one at oblique incidence. The introduction of the set of nondimensional parameters allows one to transform the reconstruction process from one search in a six-dimensional space to two searches in three-dimensional spaces (one search for normal incidence and one for oblique). Thickness, density, and longitudinal and shear elastic moduli of the coating are calculated from the nondimensional parameters determined. The sensitivity of the method to individual properties and its stability against experimental noise are studied and the inversion algorithm is accordingly optimized. An example of the method and experimental measurement for comparison is given for a polypropylene coating on a steel foil. PMID:11350002

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

    NASA Astrophysics Data System (ADS)

    Huang, Ing-Bang

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

  16. Design Review Report for Concrete Cover Block Replaced by Steel Plate

    SciTech Connect

    JAKA, O.M.

    2000-07-27

    The design for the steel cover plates to replace concrete cover blocks for U-109 was reviewed and approved in a design review meeting. The design for steel plates to replace concrete blocks were reviewed and approved by comparison and similarity with U-109 for the following additional pits: 241-U-105. 241-I-103, 241-Ax-101. 241-A-101, 241-SX-105, 241-S-A, 241-S-C, 241-SX-A.

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

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

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

  18. Influence of piezoceramic to fused silica plate thickness on the radii of curvature of piezoelectric bimorph mirror

    NASA Astrophysics Data System (ADS)

    Libu, M.; Susanth, S.; Vasanthakumari, K. G.; Dileep Kumar, C. J.; Raghu, N.

    2012-01-01

    Piezoelectric based bimorph mirrors (PBM) find extensive use in focusing of x-ray beams. Many optical instruments require use of PBM whose radii of curvature can be tuned precisely. The 100 mm and 300 mm PBMs were fabricated with varying piezoelectric to fused silica plate thicknesses. The radii of curvature of free standing mirrors were measured as a function of voltage and it was found to decrease with increasing voltage. For a given piezoelectric plate thickness, as the fused silica thickness increases, the radii of curvature was found to increase owing to increase in stiffness of the mirror. On the other hand, for a given fused silica plate thickness, when the piezoelectric plate thickness is increased, the radii of curvature are decreased for a given electric field, due to increase in generated force. This study brings out the influence of piezoceramic to fused silica plate thickness on the radii of curvature of PBM.

  19. Selection of parameters on laser cutting mild steel plates taking account of some manufacturing purposes

    NASA Astrophysics Data System (ADS)

    Asano, Hiroshi; Suzuki, Jippei; Kawakami, Hiroshi; Eguchi, Hiroshi

    2003-11-01

    There are large number of processing conditions which can be set for laser-cutting of plate materials, because importance of the objective for the cutting is different from product to product. This study aims to build a system which can set the processing conditions reasonably and efficiently. From plural processing objectives, roughness of cutting surface was taken up from among the required qualities, such as processing speed, circularity of a processed hole, height of dross on the rear side, roughness of cutting surfaces, accuracy of shapes and dimensions, and with of burning, to review the effects of the processing condition on the cutting surface including the drag line gap. In our experiments, a 1 kW CO2 gas laser machine was used to make laser-cutting samples and 389 combinations of samples were used. From the results of the experiments, the range of processing conditions which allow cutting is defined by the energy input per unit area HIA = 4.8 [J/mm2]. The values of roughness of the cutting surface on both front and rear sides of the plates can be reduced if the cutting speed is 1000 mm/min or higher, and they little change at small values if the heat input per unit area is within a range under 20 J/mm2. In a range of thin plate thickness, the drag gap on cutting surfaces can be evaluated by the heat input per unit area. In the case of thicker plate, the greater the duty is, the smaller the drag gap is, if the heat input per units area is kept unchanged. Cutting with small heat input is desirable for better roughness of cutting surface. Cutting with large heat input is required for better drag gap. In the scope of our study, a value 20 J/mm2 of heat input per unit area is recommended for laer-cutting of 0.8 - 4.5 mm thick mild steel plates.

  20. 49 CFR Appendix C to Part 178 - Nominal and Minimum Thicknesses of Steel Drums and Jerricans

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Nominal and Minimum Thicknesses of Steel Drums and Jerricans C Appendix C to Part 178 Transportation Other Regulations Relating to Transportation PIPELINE AND... SPECIFICATIONS FOR PACKAGINGS Pt. 178, App. C Appendix C to Part 178—Nominal and Minimum Thicknesses of...

  1. 49 CFR Appendix C to Part 178 - Nominal and Minimum Thicknesses of Steel Drums and Jerricans

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Nominal and Minimum Thicknesses of Steel Drums and Jerricans C Appendix C to Part 178 Transportation Other Regulations Relating to Transportation (Continued...) SPECIFICATIONS FOR PACKAGINGS Pt. 178, App. C Appendix C to Part 178—Nominal and Minimum Thicknesses of...

  2. 49 CFR Appendix C to Part 178 - Nominal and Minimum Thicknesses of Steel Drums and Jerricans

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Nominal and Minimum Thicknesses of Steel Drums and Jerricans C Appendix C to Part 178 Transportation Other Regulations Relating to Transportation (Continued...) SPECIFICATIONS FOR PACKAGINGS Pt. 178, App. C Appendix C to Part 178—Nominal and Minimum Thicknesses of...

  3. 49 CFR Appendix C to Part 178 - Nominal and Minimum Thicknesses of Steel Drums and Jerricans

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Nominal and Minimum Thicknesses of Steel Drums and Jerricans C Appendix C to Part 178 Transportation Other Regulations Relating to Transportation (Continued...) SPECIFICATIONS FOR PACKAGINGS Pt. 178, App. C Appendix C to Part 178—Nominal and Minimum Thicknesses of...

  4. 49 CFR Appendix C to Part 178 - Nominal and Minimum Thicknesses of Steel Drums and Jerricans

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Nominal and Minimum Thicknesses of Steel Drums and Jerricans C Appendix C to Part 178 Transportation Other Regulations Relating to Transportation (Continued...) SPECIFICATIONS FOR PACKAGINGS Pt. 178, App. C Appendix C to Part 178—Nominal and Minimum Thicknesses of...

  5. 75 FR 59744 - Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-28

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

  6. 78 FR 50378 - Diffusion-Annealed, Nickel-Plated Flat-Rolled Steel Products From Japan: Postponement of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-19

    ... steel products from Japan. See Diffusion- Annealed, Nickel-Plated Flat-Rolled Steel Products From Japan: Initiation of Antidumping Duty Investigation, 78 FR 23905 (April 23, 2013). The current deadline for the... International Trade Administration Diffusion-Annealed, Nickel-Plated Flat-Rolled Steel Products From...

  7. 78 FR 67334 - Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From Ukraine; Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-12

    ... Carbon Steel Plate From Ukraine; Administrative Review, 78 FR 46570 (August 1, 2013) and accompanying...: Certain Cut-to-Length Carbon Steel Plate from Ukraine, 73 FR 57602 (October 3, 2008) (Agreement). On... covering Metinvest Holding LLC (Metinvest) and its affiliated companies Azovstal Iron & Steel...

  8. 78 FR 73827 - Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From the Russian Federation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-09

    ... Certain Cut-to-Length Carbon Steel Plate from the Russian Federation, 68 FR 3859 (January 27, 2003... International Trade Administration Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From the... of an administrative review of the suspension agreement on certain cut-to-length carbon steel...

  9. The Transition from Thick to Thin Plate Wake Physics: Whither Vortex Shedding?

    NASA Technical Reports Server (NTRS)

    Rai, Man Mohan

    2016-01-01

    The near and very near wake of a flat plate with a circular trailing edge is investigated with data from direct numerical simulations. Computations were performed for six different combinations of the Reynolds numbers based on plate thickness (D) and boundary layer momentum thickness upstream of the trailing edge (theta). Unlike the case of the cylinder, these Reynolds numbers are independent parameters for the flat plate. The separating boundary layers are turbulent in all the cases investigated. One objective of the study is to understand the changes in the wake vortex shedding process as the plate thickness is reduced (increasing theta/D). The value of D varies by a factor of 16 and that of theta by approximately 5 in the computations. Vortex shedding is vigorous in the low theta/D cases with a substantial decrease in shedding intensity in the large theta/D cases. Other shedding characteristics are also significantly altered with increasing theta/D. A visualization of the shedding process in the different cases is provided and discussed. The basic shedding mechanism is explored in depth. The effect of changing theta/D on the time-averaged, near-wake velocity statistics is also discussed. A functional relationship between the shedding frequency and the Reynolds numbers mentioned above is obtained.

  10. Postbuckling response of long thick plates loaded in compression including higher order transverse shearing effects

    NASA Technical Reports Server (NTRS)

    Stein, Manuel; Sydow, P. Daniel; Librescu, Liviu

    1990-01-01

    Buckling and postbuckling results are presented for compression-loaded simply-supported aluminum plates and composite plates with a symmetric lay-up of thin + or - 45 deg plies composed of many layers. Buckling results for aluminum plates of finite length are given for various length-to-width ratios. Asymptotes to the curves based on buckling results give N(sub xcr) for plates of infinite length. Postbuckling results for plates with transverse shearing flexibility are compared to results from classical theory for various width-to-thickness ratios. Characteristic curves indicating the average longitudinal direct stress resultant as a function of the applied displacements are calculated based on four different theories: Classical von Karman theory using the Kirchoff assumptions, first-order shear deformation theory, higher-order shear deformation theory, and 3-D flexibility theory. Present results indicate that the 3-D flexibility theory gives the lowest buckling loads. The higher-order shear deformation theory has fewer unknowns than the 3-D flexibility theory but does not take into account through-the-thickness effects. The figures presented show that small differences occur in the average longitudinal direct stress resultants from the four theories that are functions of applied end-shortening displacement.

  11. Evaluation of Palatal Plate Thickness of Maxillary Prosthesis on Phonation- A Comparative Clinical Study

    PubMed Central

    B, Sreedevi; Anne, Gopinadh; Manne, Prakash; Bindu O, Swetha Hima; Atla, Jyothi; Deepthi, Sneha; Chaitanya A, Krishna

    2014-01-01

    Background: Prosthodontic treatment involves clinical procedures which influence speech performance directly or indirectly. Prosthetic rehabilitation of missing teeth with partial or complete maxillary removable dentures influences the individual voice characteristics like Phonation, resonance etc. Aim: To evaluate the effect of Acrylic palatal plate thickness (1mm-3mm) of maxillary prosthesis on phonation. Materials and Methods: Twelve subjects were selected randomly between the age group of 20-25 years who have full complement of teeth and have no speech problems. Speech evaluation was done under four experimental conditions i.e. Without any experimental acrylic palatal plate (control), with experimental acrylic palatal plates of thickness 1 mm, 2 mm and 3 mm respectively. The speech material for phonation test consisted of Vowels sounds /a/, /i/, and /o/. Speech analysis to assess phonation was done using digital acoustic analysis (PRAAT software). The obtained results were statistically analyzed by One-way ANOVA and Tukey’s multiple post-hoc for comparison of four experimental conditions with respect to different vowel sounds. Results: Mean harmonics to noise ratio (HNR) values obtained for all the Experimental conditions did not show significant difference (p>0.05). In conclusion, an increase in the thickness of the acrylic palatal plate of maxillary prosthesis for about 1 mm - 3mm in complete or partial maxillary removable dentures resulted in no significant effect on phonation of vowel sounds /a/, /i/ and /o/. Conclusion: Increasing the thickness of the palatal plate from 1 mm to 3 mm has not shown any significant effect on the phonation. PMID:24959508

  12. Failure analysis of stainless steel femur fixation plate.

    PubMed

    Hussain, P B; Mohammad, M

    2004-05-01

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

  13. A discrete particle approach to simulate the combined effect of blast and sand impact loading of steel plates

    NASA Astrophysics Data System (ADS)

    Børvik, T.; Olovsson, L.; Hanssen, A. G.; Dharmasena, K. P.; Hansson, H.; Wadley, H. N. G.

    2011-05-01

    The structural response of a stainless steel plate subjected to the combined blast and sand impact loading from a buried charge has been investigated using a fully coupled approach in which a discrete particle method is used to determine the load due to the high explosive detonation products, the air shock and the sand, and a finite element method predicts the plate deflection. The discrete particle method is based on rigid, spherical particles that transfer forces between each other during collisions. This method, which is based on a Lagrangian formulation, has several advantages over coupled Lagrangian-Eulerian approaches as both advection errors and severe contact problems are avoided. The method has been validated against experimental tests where spherical 150 g C-4 charges were detonated at various stand-off distances from square, edge-clamped 3.4 mm thick AL-6XN stainless steel plates. The experiments were carried out for a bare charge, a charge enclosed in dry sand and a charge enclosed in fully saturated wet sand. The particle-based method is able to describe the physical interactions between the explosive reaction products and soil particles leading to a realistic prediction of the sand ejecta speed and momentum. Good quantitative agreement between the experimental and predicted deformation response of the plates is also obtained.

  14. Development of low-cost welding procedures for thick sections of HY-150 steel

    NASA Technical Reports Server (NTRS)

    Schmidt, P. M.; Snow, R. S.

    1972-01-01

    Low cost welding procedures were developed for welding 6-inch thick HY-150 steel to be used in the manufacture of large diameter motor case Y rings and nozzle attachment flanges. An extensive investigation was made of the mechanical and metallurgical properties and fracture toughness of HY-150 base plate and welds made with manual shielded metal arc process and semi-automatic gas metal arc process in the flat position. Transverse tensiles, all-weld metal tensiles, Charpy V-notch specimens and edge notched bend specimens were tested in the course of the program. In addition metallographic studies and hardness tests were performed on the weld, weld HAZ and base metal. The results of the work performed indicate that both the shielded metal arc and gas metal arc processes are capable of producing consistently sound welds as determined by radiographic and ultrasonic inspection. In addition, the weld metal, deposited by each process was found to exhibit a good combination of strength and toughness such that the selection of a rolled and welded procedure for fabricating rocket motor case components would appear to be technically feasible.

  15. Rehabilitation of Composite Steel Bridges Using GFRP Plates

    NASA Astrophysics Data System (ADS)

    Damatty, A. A.; Abushagur, M.; Youssef, M. A.

    2005-09-01

    The current study is a part of an extensive research program conducted to assess the use of Glass Fibre Reinforced Plastic (GFRP) sheets in enhancing the flexural capacity of steel beams. The properties of a heavy-duty adhesive system that can be used to bond GFRP sheets to the flanges of steel beams were experimentally determined in a previous study. The excellent performance of a W-shaped steel beam strengthened using GFRP sheets has encouraged the authors to assess the applicability of this technique to composite steel bridges.

  16. Electrical optimization of power delivery through thick steel barriers using piezoelectric transducers

    NASA Astrophysics Data System (ADS)

    Lawry, T. J.; Wilt, K. R.; Roa-Prada, S.; Ashdown, J. D.; Saulnier, G. J.; Scarton, H. A.; Das, P. K.; Pinezich, J. D.

    2010-04-01

    In many commercial, industrial, and military applications, supplying power to electronics through a thick metallic barrier without compromising its structural integrity would provide tremendous advantages over many existing barrier-penetrating techniques. The Faraday shielding presented by thick metallic barriers prevents the use of electromagnetic power-transmission techniques. This work describes the electrical optimization of continuouswave power delivery through thick steel barriers using ultrasound. Ultrasonic channels are formed by attaching pairs of coaxially-aligned piezoelectric transducers to opposite sides of thick steel blocks. The thickness of the steel considered is on the order of, or greater than, one quarter wavelength of the acoustic power signal inside of steel, requiring the use of wave propagation theory to properly analyze the system. A characterization and optimization methodology is presented which measures the linear two-port electrical scattering parameters of the transducersteel- transducer channel. Using these measurements, the simultaneous conjugate impedance-matching conditions at both transducers are calculated, and electrical matching-networks are designed to optimize the power transfer from a 50Ω power amplifier on one side of the steel block to a 50Ω load on the opposite side. In addition, the impacts of, and interactions between, transducer and steel geometries are discussed, and some general guidelines for selecting their relationships are presented. Measurements of optimized systems using transducers designed to resonate at 1 MHz with diameters from 12.7 mm to 66.7 mm, and steel block thicknesses from 9.5 mm to 63.5 mm, reveal power transfer efficiencies as high as 55%, and linear delivery of 81 watts through an optimized channel.

  17. Nonlinear theory for laminated and thick plates and shells including the effects of transverse shearing

    NASA Technical Reports Server (NTRS)

    Stein, M.

    1985-01-01

    Nonlinear strain displacement relations for three-dimensional elasticity are determined in orthogonal curvilinear coordinates. To develop a two-dimensional theory, the displacements are expressed by trigonometric series representation through-the-thickness. The nonlinear strain-displacement relations are expanded into series which contain all first and second degree terms. In the series for the displacements only the first few terms are retained. Insertion of the expansions into the three-dimensional virtual work expression leads to nonlinear equations of equilibrium for laminated and thick plates and shells that include the effects of transverse shearing. Equations of equilibrium and buckling equations are derived for flat plates and cylindrical shells. The shell equations reduce to conventional transverse shearing shell equations when the effects of the trigonometric terms are omitted and to classical shell equations when the trigonometric terms are omitted and the shell is assumed to be thin.

  18. An equilibrium method for prediction of transverse shear stresses in a thick laminated plate

    NASA Technical Reports Server (NTRS)

    Chaudhuri, R. Z.

    1986-01-01

    First two equations of equilibrium are utilized to compute the transverse shear stress variation through thickness of a thick laminated plate after in-plane stresses have been computed using an assumed quadratic displacement triangular element based on transverse inextensibility and layerwise constant shear angle theory (LCST). Centroid of the triangle is the point of exceptional accuracy for transverse shear stresses. Numerical results indicate close agreement with elasticity theory. An interesting comparison between the present theory and that based on assumed stress hybrid finite element approach suggests that the latter does not satisfy the condition of free normal traction at the edge. Comparison with numerical results obtained by using constant shear angle theory suggests that LCST is close to the elasticity solution while the CST is closer to classical (CLT) solution. It is also demonstrated that the reduced integration gives faster convergence when the present theory is applied to a thin plate.

  19. Refined shear correction factor for very thick simply supported and uniformly loaded isosceles right triangular auxetic plates

    NASA Astrophysics Data System (ADS)

    Lim, Teik-Cheng

    2016-05-01

    For moderately thick plates, the use of First order Shear Deformation Theory (FSDT) with a constant shear correction factor of 5/6 is sufficient to take into account the plate deflection arising from transverse shear deformation. For very thick plates, the use of Third order Shear Deformation Theory (TSDT) is preferred as it allows the shear strain distribution to be varied through the plate thickness. Therefore no correction factor is required in TSDT, unlike FSDT. Due to the complexity involved in TSDT, this paper obtains a more accurate shear correction factor for use in FSDT of very thick simply supported and uniformly loaded isosceles right triangular plates based on the TSDT. By matching the maximum deflections for this plate according to FSDT and TSDT, a variable shear correction factor is obtained. Results show that the shear correction factor for the simplified TSDT, i.e. 14/17, is least accurate. The commonly adopted shear correction factor of 5/6 in FSDT is valid only for very thin or highly auxetic plates. This paper provides a variable shear correction for FSDT deflection that matches the plate deflection by TSDT. This variable shear correction factor allows designers to justify the use of a commonly adopted shear correction factor of 5/6 even for very thick plates as long as the Poisson’s ratio of the plate material is sufficiently negative.

  20. Mechanical response of thick laminated beams and plates subject to out-of-plane loading

    NASA Technical Reports Server (NTRS)

    Hiel, C. C.; Brinson, . F.

    1989-01-01

    The use of simplified elasticity solutions to determine the mechanical response of thick laminated beams and plates subject to out-of-plane loading is demonstrated. Excellent results were obtained which compare favorably with theoretical, numerical and experimental analyses from other sources. The most important characteristic of the solution methodology presented is that it combines great mathematical precision with simplicity. This symbiosis has been needed for design with advanced composite materials.

  1. Thick Plate Rolling—a Numerical Approach in Comparison with Analytics and Experimental Data

    NASA Astrophysics Data System (ADS)

    Prommer, Hannes; Bojahr, Manuel; Tschullik, Ralf; Kaeding, Patrick

    2011-05-01

    Today, wind turbines are mostly made of glass or carbon fibre. The manufacturing process leads to high precision and quality of the final product. Nevertheless, this fabrication method of rotor blades is very cost intensive and its production technology is not the best in terms of recyclability. In addition to its good recyclability, the handling of steel is well known and its fabrication is inexpensive. Due to these facts an idea of foils to be produced from steel arose. In cooperation with a metal forming company the 3-Dimensional rolling concept came up. Initially, rolling experiments with cold lead plates in a scale of 1:4 are made to simulate the later on used hot steel plates. Such an approach has to be accompanied by fundamental research. This paper sketches the lead rolling experiment and gives an assessment if it is applicable for a hot rolling process with steel. For this purpose, the lead test data are interpreted, the numerical model is explained and results are presented. Furthermore, an analytical flat rolling approach is used to calculate process parameters like stamping force of the upper roll and necessary friction. The applicability and precision of the analytical results are discussed in comparison with the results of the FEM model and the experimental data. Concluding the paper, validity and pitfalls of this concept are outlined and a short outlook for further research is given. The purpose of these considerations is to get closer to process parameters for an experiment in full scale for hot rolling of a rotor blade.

  2. Toughening mechanisms of a high-strength acicular ferrite steel heavy plate

    NASA Astrophysics Data System (ADS)

    Cao, Zhi-Qiang; Bao, Yan-Ping; Xia, Zheng-Hai; Luo, Deng; Guo, Ai-Min; Wu, Kai-Ming

    2010-10-01

    An ultra-low carbon acicular ferrite steel heavy plate was obtained with an advanced thermo-mechanical control process-relaxed precipitation controlled transformation (TMCP-RPC) at Xiangtan Steel, Valin Group. The heavy plate has a tensile strength of approximately 600 MPa with a lower yield ratio. The impact toughness of the heavy plate achieves 280 J at -40°C. The fine-grained mixed microstructures of the heavy plate mainly consist of acicular ferrite, granular bainite, and polygonal ferrite. The high strength and excellent toughness of the heavy plate are attributed to the formation of acicular ferrite microstructure. The prevention of blocks of martensite/retained austenite (M/A) and the higher cleanness are also responsible for the superior toughness.

  3. Thickness effects on a cracked aluminum plate with composite patch repair

    NASA Astrophysics Data System (ADS)

    Schubbe, Joel Jon

    Post-repair fatigue crack growth was investigated in 3.175, 4.826, and 6.35 mm thick aluminum panels (508 mm long, 153 mm wide), asymmetrically repaired with boron/epoxy composite patches bonded to the plates with FM73 sheet adhesive. Patches were uniaxial with patch to panel stiffness ratios ranging from 0.46 to 1.3. Experimental fatigue tests were carried out at 120 MPa, R = 0.1, and 10 Hz (sinusoidal) to measure patched and unpatched face crack lengths, center crack opening displacements, and selected strains. Crack growth data was acquired using optical, eddy current, and post-test analysis methods. Crack growth rates were calculated using the incremental polynomial method. Test results showed increased plate thickness caused increased fatigue crack growth rates in both unrepaired and repaired panels. Thermally-induced bending due to patch bonding affects crack growth rates. Increased stiffness ratios increased life-spans and reduced crack growth anomalies such as retardation. Disbond growth is more dependent on crack size than on patch configuration and tends to accelerate when the crack grows beyond a critical length or where the patch changes thickness. A three-layer Mindlin plate finite element model was used as a two-dimensional analytical technique to predict patched and unpatched face reaction loads and displacements. This method uses a third plate layer to model the adhesive layer as a continuum. Constraint equations are used to enforce compatibility conditions along the plate-adhesive and adhesive patch interfaces. The calculated loads and displacements, in conjunction with the modified crack closure method, were used to compute stress intensity factors for the crack tips. Crack growth rates were calculated using experimentally determined material constants and the fatigue crack growth relationship (Paris Law) of the unpatched plate. Comparisons of the experimental to analytical curvatures of repaired panels showed excellent agreement for crack lengths

  4. A Study on Segmented Multiple-Step Forming of Doubly Curved Thick Plate by Reconfigurable Multi-Punch Dies

    SciTech Connect

    Ko, Young Ho; Han, Myoung Soo; Han, Jong Man

    2007-05-17

    Doubly curved thick plate forming in shipbuilding industries is currently performed by a thermal forming process, called as Line Heating by using gas flame torches. Due to the empirical manual work of it, the industries are eager for an alternative way to manufacture curved thick plates for ships. It was envisaged in this study to manufacture doubly curved thick plates by the multi-punch die forming. Experiments and finite element analyses were conducted to evaluate the feasibility of the reconfigurable discrete die forming to the thick plates. Single and segmented multiple step forming procedures were considered from both forming efficiency and accuracy. Configuration of the multi-punch dies suitable for the segmented multiple step forming was also explored. As a result, Segmented multiple step forming with matched dies had a limited formability when the objective shapes become complicate, while a unmatched die configuration provided better possibility to manufacture large curved plates for ships.

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

    SciTech Connect

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

    2007-07-01

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

  6. Single Transducer Ultrasonic Imaging Method that Eliminates the Effect of Plate Thickness Variation in the Image

    NASA Technical Reports Server (NTRS)

    Roth, Don J.

    1996-01-01

    This article describes a single transducer ultrasonic imaging method that eliminates the effect of plate thickness variation in the image. The method thus isolates ultrasonic variations due to material microstructure. The use of this method can result in significant cost savings because the ultrasonic image can be interpreted correctly without the need for machining to achieve precise thickness uniformity during nondestructive evaluations of material development. The method is based on measurement of ultrasonic velocity. Images obtained using the thickness-independent methodology are compared with conventional velocity and c-scan echo peak amplitude images for monolithic ceramic (silicon nitride), metal matrix composite and polymer matrix composite materials. It was found that the thickness-independent ultrasonic images reveal and quantify correctly areas of global microstructural (pore and fiber volume fraction) variation due to the elimination of thickness effects. The thickness-independent ultrasonic imaging method described in this article is currently being commercialized under a cooperative agreement between NASA Lewis Research Center and Sonix, Inc.

  7. Buckling analysis of moderately thick rectangular plates using coupled displacement field method

    NASA Astrophysics Data System (ADS)

    Meera Saheb, K.; Aruna, K.

    2015-12-01

    A simple and efficient coupled displacement field method is developed to study the buckling load parameters of the moderately thick rectangular plates. This method has been successfully applied to study the same for the Timoshenko beams. A single term trigonometric admissible displacement field is assumed for one of the variables, say, the total rotations (in both X, Y directions). Making use of the coupling equations, the spatial variation for the remaining lateral displacement field is derived in terms of the total rotations. The coupled displacement field method makes the energy formulation to contains half the number of unknown independent coefficients, in the case of a rectangular plate, contrary to the conventional Rayleigh-Ritz method. The expressions for the non-dimensional buckling load parameters of the moderately thick rectangular plates with all the edges simply supported are derived. The numerical values of these parameters obtained using the coupled displacement field method match very well with open literature demonstrating the effectiveness of the coupled displacement field method.

  8. Review on Electroless Plating Ni-P Coatings for Improving Surface Performance of Steel

    NASA Astrophysics Data System (ADS)

    Zhang, Hongyan; Zou, Jiaojuan; Lin, Naiming; Tang, Bin

    2014-04-01

    Electroless plating has been considered as an effective approach to provide protection and enhancement for metallic materials with many excellent properties in engineering field. This paper begins with a brief introduction of the fundamental aspects underlying the technological principles and conventional process of electroless nickel-phosphorus (Ni-P) coatings. Then this paper discusses different electroless nickel plating, including binary plating, ternary composite plating and nickel plating with nanoparticles and rare earth, with the intention of improving the surface performance on steel substrate in recent years in detail. Based on different coating process, the varied features depending on the processing parameters are highlighted. Separately, diverse preparation techniques aiming at improvement of plating efficiency are summarized. Moreover, in view of the outstanding performance, such as corrosion resistance, abrasive resistance and fatigue resistance, this paper critically reviews the behaviors and features of various electroless coatings under different conditions.

  9. A large-deformation thin plate theory with application to one-atom-thick layers

    NASA Astrophysics Data System (ADS)

    Delfani, M. R.; Shodja, H. M.

    2016-02-01

    Nowadays, two-dimensional materials due to their vast engineering and biomedical applications have been the focus of many researches. The present paper proposes a large-deformation theory for thin plates with application to one-atom-thick layers (OATLs). The deformation is formulated exactly in the mathematical framework of Lagrangian description. In particular, an exact finite strain analysis is given - in addition to the usual strain tensor associated to the middle surface, the second and third fundamental forms of the middle surface of the deformed thin plate are also maintained in the analysis. Exact closed-form solutions for a uniaxially curved thin plate due to pure bending in one case and due to a combination of vertical and horizontal loading in another are obtained. As a special case of the latter problem, the exact solution for the plane-strain bulge test of thin plates is derived. Subsequently, the approximation of Vlassak and Nix [Vlassak, J.J., Nix, W.D., 1992. J. Mater. Res., 7(12), 3242-3249] for the load-deflection equation is recovered. The given numerical results are devoted to graphene as the most well-known OATL.

  10. 75 FR 22555 - Certain Cut-to-Length Carbon-Quality Steel Plate from the Republic of Korea: Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-29

    ... Revocation in Part, 75 FR 15679, 15681 (March 30, 2010) (Initiation Notice). The two companies identified in... International Trade Administration Certain Cut-to-Length Carbon-Quality Steel Plate from the Republic of Korea... administrative review of the antidumping duty order on certain cut-to-length carbon-quality steel plate...

  11. 75 FR 29976 - Certain Cut-to-Length Carbon-Quality Steel Plate Products From Italy: Extension of the Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-28

    ... Administrative Review, 75 FR 4779 (January 29, 2010). The review covers the period February 1, 2008, through... International Trade Administration Certain Cut-to-Length Carbon-Quality Steel Plate Products From Italy... antidumping duty order on certain cut-to-length carbon-quality steel plate products from Italy. See...

  12. 76 FR 66271 - Stainless Steel Plate in Coils From Belgium: Notice of Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

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

  13. 75 FR 62103 - Stainless Steel Plate in Coils From South Africa: Final Results of Expedited Sunset Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

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

  14. 77 FR 38825 - Clad Steel Plate From Japan; Scheduling of a Full Five-Year Review Concerning the Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ... were such that a full review pursuant to section 751(c)(5) of the Act should proceed (77 FR 37439, June... COMMISSION Clad Steel Plate From Japan; Scheduling of a Full Five-Year Review Concerning the Antidumping Duty Order on Clad Steel Plate From Japan AGENCY: United States International Trade Commission....

  15. 76 FR 8772 - Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan and Korea

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... the domestic interested party group response to its notice of institution (75 FR 67108, November 1... COMMISSION Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan and Korea AGENCY: United...-year reviews concerning the countervailing duty orders on cut-to-length carbon steel plate from...

  16. 77 FR 32517 - Stainless Steel Plate in Coils From Belgium: Notice of Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

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

  17. 76 FR 22725 - Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan, and Korea; Scheduling of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... (76 FR 8772, February 15, 2011). A record of the Commissioners' votes, the Commission's statement on... COMMISSION Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan, and Korea; Scheduling of...-Length Carbon Steel Plate From India, Indonesia, Italy, Japan, and Korea AGENCY: United...

  18. Feasibility study on welding and cutting methods for thick plate in fusion reactor

    SciTech Connect

    Osaki, T.; Nakayama, Y.; Kobayashi, T.

    1995-12-31

    Application of tungsten-arc inert-gas (TIG) welding with narrow gap has been considered as a hopeful joint method to suppress post welding deformation for thick plates. The authors studied some parameters to predict the post-welding deformation for the narrow gap shape of TIG welding. As for cutting methods, the water jet method was applied for weld joints in this study. Reweld tests by using the TIG welding method were successfully performed under the condition of cutting surface as it was. Results of tensile tests for reweld joints showed no reduction in strength. This reveals a good prospect of providing reweld groove surface without any machining on site.

  19. Axisymmetric Distributions of Thick Circular Plate in a Modified Couple Stress Theory

    NASA Astrophysics Data System (ADS)

    Kumar, Rajneesh; Marin, Marin; Abbas, Ibrahim A.

    2015-07-01

    In this paper, the two-dimensional axisymmetric distributions of thick circular plate in modified couple stress theory with heat and mass diffusive sources is investigated. The problem is considered in the context of the theories of thermodiffusion elastic solid with one and two relaxation time developed by Sherief et al. [Int. J. Eng. Sci. 42, 591 (2004)] and Kumar and Kansal [Int. J. Solid Struct. 45, 5890 (2008)] by using Laplace and Hankel transforms technique. The displacements, stress components, temperature change and chemical potential are obtained in transformed domain. Particular cases of interest are also deduced.

  20. An analysis of thickness-shear vibrations of doubly-rotated quartz crystal plates with the corrected first-order Mindlin plate equations.

    PubMed

    Du, Jianke; Wang, Wenjun; Chen, Guijia; Wu, Rongxing; Huang, Dejin; Ma, Tingfeng; Wang, Ji

    2013-11-01

    The Mindlin plate equations have been widely used in the analysis of high-frequency vibrations of quartz crystal resonators with accurate solutions, as demonstrated by the design procedure based on analytical results in terms of frequency, mode shapes, and optimal parameters for the AT-cut quartz crystal plate, which is the core element in a resonator structure. Earlier studies have been focused on the AT-cut (which is one type of rotated Y-cut) quartz crystal plates because it is widely produced and has relatively simple couplings of vibration modes at thickness-shear frequencies of the fundamental and overtone modes. The simplified equations through the truncation, correction, and modification of the Mindlin plate equations have been widely accepted for practical applications, and further efforts to expand their applications to similar problems of other material types, such as doubly-rotated quartz crystals, with the SC-cut being a typical and popular one, are also naturally expected. We have found out that the Mindlin plate theory can be truncated and corrected for the SC-cut quartz crystal plates in a manner similar to the AT-cut plates. The analytical results show that the corrected Mindlin plate equations are equally accurate and convenient for obtaining essential design parameters of resonators for the thickness-shear vibrations of SC-cut quartz crystal plates. PMID:24158292

  1. Electron beam welding of titanium and Ti-6AL-4V Thick plates

    NASA Astrophysics Data System (ADS)

    Kohyama, Akira; Arata, Yoshiaki; Tomie, Michio; Igata, Naohiro

    1984-05-01

    This paper reports work as thick weld process development for Ti and Ti alloys in fusion reactor applications. The materials used are pure Ti and Ti-6A1-4V with a maximum plate thickness of 56 mm I-butt welded by a 100KW electron beam welding facility at Osaka University. Optimum welding conditions produced sound welded I-butt joints without detectable defects by X-ray when evaluated with tensile test and micro-Vickers hardness test. The microstructures of the welded joints were investigated with TEM and SEM. These results showed that welded joints were quite sound and were possibly acceptable as structural components of fusion reactor even in as welded state.

  2. Effect of Thickness and Fibre Volume Fraction on Impact Resistance of Steel Fibre Reinforced Concrete (SFRC)

    NASA Astrophysics Data System (ADS)

    Che Muda, Zakaria; Usman, Fathoni; Syamsir, Agusril; Shao Yang, Chen; Nasharuddin Mustapha, Kamal; Beddu, Salmia; Thiruchelvam, Sivadass; Liyana Mohd Kamal, Nur; Ashraful Alam, Md; Birima, Ahmed H.; Itam, Zarina; Zaroog, O. S.

    2016-03-01

    This paper investigate the effect of the thickness and fibre volume fraction (VF) on the impact performance of steel fibre reinforced concrete (SFRC) for the concrete slab of 300mm × 300mm size reinforced subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at 0.57 m height has been used in this research work. The objective of this research is to study the relationship of impact resistance SFRC against slab thickness and volume fraction. There is a good linear correlation between impact resistances of SFRC against slab thickness. However the impact resistance of SFRC against percentage of volume fraction exhibit a non-linear relationship.

  3. Metallurgical design basis, qualification testing, and production history of 50 ksi and 60 ksi steel plate for the MARS TLP deck fabrication

    SciTech Connect

    Suzuki, Shuichi; Sueda, Kyosuke; Iki, Hiroshi; Smith, J.D.

    1995-12-31

    The MARS TLP fast-track deck construction project required rapid qualification and production of 50 ksi and 60 ksi steel plate. This paper describes the development of high-performance 4 in. (101.6mm) 50 ksi and 3 in. (76.2mm) 60 ksi steels of a modified API 2W composition and presents the production history for the MARS deck steel order. The same base composition was used for both grades via innovative proprietary TMCP practice. Utilization of the mono-chemistry steel allowed for production of a wide range of thicknesses and grades in a very short time frame via a simplified melting schedule and made it possible to minimize the number of new welding procedures to be developed by the deck fabricator. Extremely low carbon equivalent allowed the implementation of low fabrication preheats, with resultant cost and fabrication schedule savings. The chemical composition of the steel was specifically designed for this project and qualification testing in accordance with API RP 2Z verified high heat-affected zone CTOD toughness free of local brittle zones over a wide range of heat input and interpass temperature. Strict production process control resulted in very tight production property histograms with all steel being verified to have Charpy V-notch transition temperatures below {minus}80 C ({minus}112 F) at the plate mid-width, mid-thickness position. The success of the MARS deck steel rapid qualification, production and delivery was enabled by close teamwork between deck design engineers, construction fabrication contractor, and steelmaker for this steel.

  4. A Model for Predicting the Yield Strength Difference between Pipe and Plate of Low-Carbon Microalloyed Steel

    NASA Astrophysics Data System (ADS)

    Zhang, Wenlong; Ding, Dongyan; Gu, Mingyuan

    2012-12-01

    A combination of finite-element calculation and tension-compression tests was employed to predict the yield strength difference between the pipe and plate of low-carbon microalloyed steel (LCMS) in the production of high-frequency straight bead welding pipes (HFSBWPs). The deformation process was divided into bending, flattening, and tension deformations. The bending and flattening deformations were simulated using a finite-element method in order to obtain circumferential strains at pipe wall positions along the wall thickness. These strains were the transition strains in the subsequent tension-compression-tension and compression-tension tests. The yield stresses (0.5 pct proof stresses) at the pipe wall positions were derived from the obtained stress-strain curves. The average of the obtained yield stresses was taken as the predicted yield strength of the pipes. It is found that the difference between the latter and the strength of the original steel plates is a result of the combined action of the Bauschinger effect and strain hardening caused by bending and reverse bending deformations. It is strongly dependent on the ratio of pipe wall thickness to pipe outer diameter ( T/D ratio). At low T/D ratios, the Bauschinger effect was dominant, resulting in a decreased yield strength. Strain hardening due to work hardening was dominant at higher T/D ratios, resulting in an increased yield strength. The increase in yield strength was greater at the inner pipe walls than at outer ones, indicating that strain hardening is stronger at inner pipe walls. The yield strength differences predicted with the presented approach are comparable with the values obtained from industrial productions of HFSBWPs, indicating that this approach can be used to predict the yield strength difference between pipe and plate of LCMS.

  5. Changes Found on Run-In and Scuffed Surfaces of Steel Chrome Plate, and Cast Iron

    NASA Technical Reports Server (NTRS)

    Good, J. N.; Godfrey, Douglas

    1947-01-01

    A study was made of run-in and scuffed steel, chrome-plate, and cast-iron surfaces. X-ray and electron diffraction techniques, micro-hardness determinations, and microscopy were used. Surface changes varied and were found to include three classes: chemical reaction, hardening, and crystallite-size alteration. The principal chemical reactions were oxidation and carburization.

  6. 76 FR 50495 - Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-15

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

  7. 76 FR 53882 - Continuation of Antidumping and Countervailing Duty Orders: Stainless Steel Plate in Coils From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

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

  8. 78 FR 79662 - Stainless Steel Plate in Coils From Belgium: Final Results of Antidumping Duty Administrative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-31

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

  9. 76 FR 28809 - Stainless Steel Plate From Belgium; Termination of Five-Year Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

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

  10. 75 FR 30434 - Stainless Steel Plate From Belgium, Italy, Korea, South Africa, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-01

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

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

    SciTech Connect

    1998-12-01

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

  12. 77 FR 2032 - Certain Cut-to-Length Carbon-Quality Steel Plate Products From the Republic of Korea: Preliminary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

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

  13. Experimental optimisation of the gas-assisted laser cutting of thick steel sheets

    SciTech Connect

    Malikov, A G; Orishich, Anatolii M; Shulyat'ev, Viktor B

    2009-06-30

    We report on the experimental optimisation of the oxygen-assisted CO{sub 2} laser cutting of low-carbon sheet steel 5 to 25 mm in thickness. It is shown that the cut edge roughness is minimal when the energy input per unit volume of the material removed and the incident beam power per unit sheet thickness remain constant at {approx}20 J mm{sup -3} and {approx}200 W mm{sup -1}, respectively, over the entire range of sheet thicknesses examined. The corresponding Peclet number is Pe = 0.5. These results can be used to determine the optimal beam power and cutting speed for a particular sheet thickness. At sufficiently large thicknesses, the conditions that ensure the minimum roughness can be written in the form of relations between nondimensional parameters. (interaction of laser radiation with matter. laser plasma)

  14. A Rapid Ultrasonic Method for Nondestructive Thickness Mapping of Bronze Liner in Steel-Backed Bearing Sleeves

    NASA Astrophysics Data System (ADS)

    Fei, Dong; Rebinsky, Douglas A.

    2004-02-01

    In this paper a nondestructive, automatic, ultrasonic scanning method was developed to permit rapid thickness mapping of the bronze liner in a steel-backed bearing sleeve. Because the sound velocity in bronze was unknown, an indirect two-step approach was used: the first step utilized a simultaneous velocity and thickness mapping method to measure the total wall thickness while the second step measured the thickness of the steel backing. The difference of the two obtained thickness maps yielded the thickness map of the bronze liner. Comparison to destructive examination results showed a measurement accuracy of approximately 20 μm or 2%.

  15. A Rapid Ultrasonic Method for Nondestructive Thickness Mapping of Bronze Liner in Steel-Backed Bearing Sleeves

    SciTech Connect

    Fei Dong; Rebinsky, Douglas A.

    2004-02-26

    In this paper a nondestructive, automatic, ultrasonic scanning method was developed to permit rapid thickness mapping of the bronze liner in a steel-backed bearing sleeve. Because the sound velocity in bronze was unknown, an indirect two-step approach was used: the first step utilized a simultaneous velocity and thickness mapping method to measure the total wall thickness while the second step measured the thickness of the steel backing. The difference of the two obtained thickness maps yielded the thickness map of the bronze liner. Comparison to destructive examination results showed a measurement accuracy of approximately 20 {mu}m or 2%.

  16. New approach to the excitation of plate waves for piezoelectric thick-film devices.

    PubMed

    De Cicco, Giorgio; Morten, Bruno

    2008-12-01

    A method is presented for exciting the propagation of plate waves in elastic guides. It is implemented in a device whose minimum working structure consists of a non-piezoelectric plane guide and two piezoelectric transducers operating as a generator and detector. The device is entirely in accordance with thick-film technology standard procedures. Both transducers are composed of a PZT ferroelectric layer deposited on a ceramic substrate and a suitable system of three coplanar metal electrodes placed inside the same layer. Beside setting the wavelength of propagation, the electrode system promotes piezoelectric deformations parallel to the substrate simultaneously contracting and extending contiguous active regions in the layer. Pure shear stresses are then induced on the involved guide surface, alternately distributed, with the spatial periodicity of the wave that will propagate in the guide. The propagation of several kinds of guided waves is possible so the selection of the one that meets a specific device design best is allowed. This work describes the design, realization and operation of a prototype structure consisting of an alumina plate guide and two pairs of piezoelectric thick-film transducers realized on it. The results related to the propagation of symmetric and asymmetric Lamb modes are reported. Moreover, the potential of the method is highlighted, emphasizing its effectiveness, easy implementation and application in the development of devices for the sensing and non-destructive testing areas. PMID:18486958

  17. An improved plate theory of order (1,2) for thick composite laminates

    NASA Technical Reports Server (NTRS)

    Tessler, A.

    1992-01-01

    A new (1,2)-order theory is proposed for the linear elasto-static analysis of laminated composite plates. The basic assumptions are those concerning the distribution through the laminate thickness of the displacements, transverse shear strains and the transverse normal stress, with these quantities regarded as some weighted averages of their exact elasticity theory representations. The displacement expansions are linear for the inplane components and quadratic for the transverse component, whereas the transverse shear strains and transverse normal stress are respectively quadratic and cubic through the thickness. The main distinguishing feature of the theory is that all strain and stress components are expressed in terms of the assumed displacements prior to the application of a variational principle. This is accomplished by an a priori least-square compatibility requirement for the transverse strains and by requiring exact stress boundary conditions at the top and bottom plate surfaces. Equations of equilibrium and associated Poisson boundary conditions are derived from the virtual work principle. It is shown that the theory is particularly suited for finite element discretization as it requires simple C(sup 0)- and C(sup -1)-continuous displacement interpolation fields. Analytic solutions for the problem of cylindrical bending are derived and compared with the exact elasticity solutions and those of our earlier (1,2)-order theory based on the assumed displacements and transverse strains.

  18. Effect of Welding Atmosphere at Bottom Surface on Welding Phenomenan in Full Penetration Laser Welding of Thick Plate

    NASA Astrophysics Data System (ADS)

    Arakane, Goro; Tsukamoto, Susumu; Honda, Hiroshi; Kuroda, Seiji; Fukushima, Takeshi

    The keyhole behaviour and bubble formation were investigated in the full penetration laser welding of 11 and 15 mm thick plate with various kinds of atmosphere at the bottom side. Prevention of some defects was also attempted. Back surface atmosphere was controlled using a shielding box fixed on the sample back surface to avoid contamination from the air and also the effect of gas flow on the keyhole behaviour. A lot of bubbles were formed during welding with the back surface atmosphere of nitrogen and air. This was deduced to be caused by supersaturation of nitrogen, which was dissolved from the backside molten pool. The critical nitrogen concentration in the weld metal to form the porosity was independent of the back surface atmosphere. Oxygen enhanced the porosity formation, since the nitrogen concentration increased in the presence of oxygen. The keyhole was significantly perturbed and hot cracking occurred in the inert gas back shielding. It was shown that the keyhole stability determined by solubility of the shielding gas in the molten steel. Aluminum coating on the sample back surface was effective in preventing the porosity due to denitrification of the molten pool and hot cracking.

  19. Properties of single shear layer instabilities and vortex-induced excitation mechanisms of thick plates

    NASA Astrophysics Data System (ADS)

    Billeter, P.

    2004-04-01

    The basic findings of an experimental investigation of flow-induced vibrations of gate plates with multiple degrees of freedom are presented. The study focused on the fluid dynamic behaviour of the single shear layer separating from a thick rectangular plate. The principal aim of the study was to further the physical understanding of instability-induced excitation mechanisms (IIE) involving shear layer instabilities and vortex generation. It is shown that this type of gate vibration is caused by two dominant excitation mechanisms: cross-flow and streamwise impinging-leading-edge-vortex (ILEV) excitation and streamwise body-resonant leading-edge-vortex-shedding (BR-LEVS) excitation. The first mechanism is caused by the local interaction of the shear layer underneath the gate plate with the trailing edge of the gate lip. The second mechanism is produced by the instability of the shear layer in the tailwater of the gate, with the instability being necessarily triggered by the elastic motion of the flow separation at the leading edge of the gate. Former address. Laboratory of Hydraulics (VAW), Swiss Federal Institute of Technology (ETH), Zurich, Switzerland.

  20. Hole Enlargement Measurement in Carbon Steel Tube Support Plate

    SciTech Connect

    Yu, Y.; Nguyen, H.; Shatat, A.; Russell, D. E.; Muthu, N.

    2006-03-06

    The standard RFT (remote field testing) technique has been found feasible for identifying and sizing tube support plate (TSP) hole enlargement caused by corrosion or erosion. Finite element simulations and experimental studies have shown that detector energy output (DEO) of a single-exciter RFT probe is a linear function of the TSP-tube gap for the gap size range studied in this research. DEO can be used to quantify the gap.

  1. Hole Enlargement Measurement in Carbon Steel Tube Support Plate

    NASA Astrophysics Data System (ADS)

    Yu, Y.; Nguyen, H.; Shatat, A.; Russell, D. E.; Muthu, N.

    2006-03-01

    The standard RFT (remote field testing) technique has been found feasible for identifying and sizing tube support plate (TSP) hole enlargement caused by corrosion or erosion. Finite element simulations and experimental studies have shown that detector energy output (DEO) of a single-exciter RFT probe is a linear function of the TSP-tube gap for the gap size range studied in this research. DEO can be used to quantify the gap.

  2. Arctic Crustal Thickness and Oceanic Lithosphere Distribution from Gravity Inversion: Constraining Plate Reconstructions

    NASA Astrophysics Data System (ADS)

    Kusznir, N. J.; Alvey, A.; Roberts, A. M.

    2013-12-01

    Mapping crustal thickness, continental lithosphere thinning and oceanic lithosphere distribution represents a substantial challenge for the Polar Regions. Using gravity anomaly inversion, we have produced the first comprehensive maps of crustal thickness and oceanic lithosphere distribution for the Arctic. The Arctic region formed as a series of small distinct ocean basins leading to a complex distribution of oceanic crust, thinned continental crust, possible micro-continents and rifted continental margins. Mapping of continental lithosphere thinning factor and crustal thickness from gravity inversion provide predictions of ocean-continent transition structure and magmatic type and continent ocean boundary location independent of magnetic isochrons. Restoration of crustal thickness and continent-ocean boundary location from gravity inversion may be used to test plate tectonic reconstructions. Using crustal thickness and continental lithosphere thinning factor maps with superimposed shaded-relief free-air gravity anomaly, we improve the determination of pre-breakup rifted margin conjugacy and sea-floor spreading trajectory within the Arctic basins. By restoring crustal thickness & continental lithosphere thinning maps of the Eurasia Basin & NE Atlantic to their initial post-breakup configuration we show the geometry and segmentation of the rifted continental margins at their time of breakup, together with the location of highly-stretched failed breakup basins and rifted micro-continents. Our gravity inversion predicts thin crust and high continental lithosphere thinning factors in the Makarov, Podvodnikov, Nautilus and Canada Basins consistent with these basins being underlain by oceanic or highly thinned continental crust. Larger crustal thicknesses, in the range 20 - 30 km, are predicted for the Lomonosov, Alpha and Mendeleev Ridges. Moho depths predicted compare well with seismic estimates. Predicted very thin continental or oceanic crust under the North Chuchki

  3. Effect of layer thickness on the properties of nickel thermal sprayed steel

    NASA Astrophysics Data System (ADS)

    Nurisna, Zuhri; Triyono, Muhayat, Nurul; Wijayanta, Agung Tri

    2016-03-01

    Thermal arc spray nickel coating is widely used for decorative and functional applications, by improving corrosion resistance, wear resistance, heat resistence or by modifying other properties of the coated materials. There are several properties have been studied. Layer thickness of nickel thermal sprayed steel may be make harder the substrate surface. In this study, the effect of layer thickness of nickel thermal sprayed steel has been investigated. The rectangular substrate specimens were coated by Ni-5 wt.% Al using wire arc spray method. The thickness of coating layers were in range from 0.4 to 1.0 mm. Different thickness of coating layers were conducted to investigate their effect on hardness and morphology. The coating layer was examined by using microvickers and scanning electron microscope with EDX attachment. Generally, the hardness at the interface increased with increasing thickness of coating layers for all specimens due to higher heat input during spraying process. Morphology analysis result that during spraying process aluminum would react with surrounding oxygen and form aluminum oxide at outer surface of splat. Moreover, porosity was formed in coating layers. However, presence porosity is not related to thickness of coating material. The thicker coating layer resulted highesr of hardness and bond strength.

  4. Effect of stiffness and thickness ratio of host plate and piezoelectric patches on reduction of the stress concentration factor

    NASA Astrophysics Data System (ADS)

    Fesharaki, Javad Jafari; Madani, Seyed Ghasem; Golabi, Sa'id

    2016-06-01

    This paper focuses on the effects of stiffness ratio and thickness ratio on reducing stress concentration factor using piezoelectric patches in a rectangular plate with a hole, as a classical shape. Various locations of actuators and induction of positive/negative strains into the host plate are investigated and the best location of patches is presented. The study investigated the ratio effects and piezoelectric patches bounded on a rectangular host plate having various thicknesses and materials. Results show that the best position of actuators varies based on values of thickness and stiffness ratios of the host plate and piezoelectric patches. Also, the location of maximum stress concentration is transmitted from top and bottom of the hole to another point around the edge by changing the location of the piezoelectric actuators. To verify the results, some experimental tests are applied. The results show good agreement between the finite element analysis and experimental tests.

  5. Analysis of transient heat flow to thick-walled plates and cylinders. [to determine gas heat transfer coefficient

    NASA Technical Reports Server (NTRS)

    Powell, W. B.

    1973-01-01

    A methodology is described for the analysis of a transient temperature measurement made in a flat or curved plate subjected to convective heat transfer, such that the surface heat flux, the hot-gas temperture, and the gas heat transfer coefficient can be determined. It is shown that if the transient temperature measurement is made at a particular point located nearly midway in the thickness of the plate there is an important simplification in the data analysis process, in that the factor relating the surface heat flux to the measured rate of rise of temperature becomes invariant for a Fourier Number above 0.60 and for all values of the Biot Number. Parameters are derived, tabulated, and plotted which enable straightforward determination of the surface heat flux, the hot-gas temperature, of the plate, the rate of rise of temperature, the plate thickness and curvature, and the mean thermal properties of the plate material at the test temperature.

  6. Influence of stack plate thickness and voltage input on the performance of loudspeaker-driven thermoacoustic refrigerator

    NASA Astrophysics Data System (ADS)

    Putra, Nandy; Agustina, Dinni

    2013-04-01

    A loudspeaker-driven thermoacoustic refrigerator has been built and tested to gain understanding of its thermal performance and the cooling rate. The influence of plate thickness made of acrylic sheet was experimentally investigated by varying plate thickness of the stack, 0.15 mm, 0.5 mm and 1 mm, respectively. The experiments were conducted with various voltage input to the driver starting from setting 4 to 9 voltage peak-to-peak. The temperatures at both ends of the stack were acquired. For all variations, thermoacoustic cooling effect occurred in seconds and escalated rapidly in two minutes and became stable in ten-minute time. The experimental results showed that higher voltage input yielded higher thermal performance and faster cooling rate. For each set of experiment, the operating frequency and other parameters of the stack were kept unchanged. The experimental results show that the thermal performance and cooling rate increase with the decrease of plate thickness. The largest temperature difference, 14.8°C, was achieved with 0.1 mm plate thickness at voltage setting 9. However, the thermal performance gained for 0.5 mm plate thickness voltage setting of 9, was arguably the optimum thickness in terms of advantages in the ease of fabricating the stack and more consistent cooling.

  7. Crack arrestability of ship hull steel plate in accidental conditions: Application of high arrestability endowed ultra fine-grain surface layer steel

    SciTech Connect

    Ishikawa, Tadashi; Hagiwara, Yukito; Oshita, Shigeru; Inoue, Takehiro; Hashimoto, Kunifumi; Kuroiwa, Takashi; Tada, Masuo; Yajima, Hiroshi

    1996-12-01

    A new type steel plate with ultra fine-grained surface layers (SUF steel) has been developed to improve crack arrestability. The application of this new type steel makes it possible to prevent catastrophic brittle fracture accidents of ship hull structures in emergency conditions, such as in serious collisions or groundings. It will reduce further the risk of casualties and environmental pollutions, caused by accidents of large crude oil carriers (VLCCs). The authors have investigated the validity for the application of the new type steel with ultra-high crack arrestability. Both computer simulations for collision of two VLCCs and large-scale fracture testings for crack arrestability have been carried out to study the accidental cases. The simulation results suggest that a collision generates a significant amount of plastic strain damage for the hull plate around a struck part. For example, the sheer strake plate near the struck part suffers 5 to 10% of plastic strain, before an inner-hull ruptures. Therefore, the effect of plastic strain (10% level) on crack arrestability of steel plates (the SUF plate and a conventional TMCP plate) was examined by standard ESSO tests, ultra wide-plate duplex ESSO tests, and sheer strake model tests. The test results are as follows: (1) Plastic strain deteriorates crack arrestability of steel plates. (2) Sufficient crack arrestability at 0 deg. C cannot be expected in the conventional TMCP steel plate plastically strained by about 10%. (3) The SUF plate maintains high crack arrestability even after introducing 10% plastic strain, at design temperature of 0 deg. C.

  8. Fracture initiation by local brittle zones in weldments of quenched and tempered structural alloy steel plate

    SciTech Connect

    Kenney, K.L.; Reuter, W.G.; Reemsnyder, H.S.; Matlock, D.K.

    1997-12-31

    The heat-affected zone (HAZ) embrittlement of an API 2Y Grade 50T quenched and tempered offshore structural steel plate, welded by the submerged-arc process at a heat input of 4.5 kJ/mm, was investigated from the viewpoint of identifying the local brittle zone (LBZ) microstructure and the metallurgical factors associated with its formation. Microstructural and fractographic analysis showed the LBZ microstructure to be dual phase martensite-austenite (M-A) constituent. The formation of M-A constituent was found to be related to microstructural banding of the hot-rolled base plate. When the banded base plate was welded, M-A constituent formed only within the band microstructure which penetrated the intercritically-reheated coarse-grain HAZ (IRCGHAZ). The chemistry of the band microstructure in conjunction with the thermal cycle of the IRCGHAZ provided the critical conditions for the formation of M-A constituent in the API 2Y Grade 50T steel investigated. The influence of local brittle zones (i.e., M-A constituent) on the HAZ fracture toughness was evaluated by means of Crack-Tip Opening Displacement (CTOD) tests. These tests showed the steel to suffer embrittlement when the fatigue precrack sampled an intercritically-reheated coarse-grain HAZ which contained M-A constituent, confirming that M-A constituent is the major microstructural factor controlling the HAZ toughness of this particular steel.

  9. Bond slip detection of steel plate and concrete beams using smart aggregates

    NASA Astrophysics Data System (ADS)

    Qin, Feng; Kong, Qingzhao; Li, Mo; Mo, Y. L.; Song, Gangbing; Fan, Feng

    2015-11-01

    The newly emerged steel plate concrete (SC), benefited from a composite effect of steel and concrete materials, has been applied to shield building and internal structures of AP1000 nuclear power plants. The detection of bond-slip between steel plate and concrete is of great importance to provide early warnings of steel plate and concrete debonding and to ensure the safety of SC structures. In this paper, an active sensing approach using smart aggregates (SAs) is developed to detect the initiation and to monitor the development of bond-slip. A SA, designed by sandwiching a fragile piezoceramic patch between protection materials, can be utilized as both actuator and sensor by taking advantage of the piezoelectricity of piezoceramic material. Two SC beams with distinct shear reinforcement ratios ≤ft({ρ }t\\right) were experimentally investigated. Based on the wavelet packet decomposition of the received signals from SAs, the initiation of bond-slip is detected, and the development of bond-slip is quantitatively monitored to better understand the structural performance of SC beams, including the stiffness and capacity. The bond-slip severities of the two SC beams are compared to study the improvement of bond-slip condition rendered by providing more shear reinforcement.

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

    SciTech Connect

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

    2010-01-01

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