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Hidekazu Murakawa - One of the best experts on this subject based on the ideXlab platform.
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shear strength of cmt brazed lap joints between aluminum and zinc coated steel
Journal of Materials Processing Technology, 2013Co-Authors: Jian Lin, Yongping Lei, Hidekazu MurakawaAbstract:Abstract Higher shear strength and Fusion Line failure were measured in CMT brazed lap joint of aluminum alloy 6061 and zinc coated steels with high strength (DP600) or thick plate (1.2 mm). Lower shear strength and interface failure were observed only if aluminum was brazed with low strength (270 MPa) and thin steel sheet (0.7 mm). A numerical model was developed for the prediction of shear strength and failure modes of the CMT lap joints. The maximum principle stress and deformation energy at the interface layer of the CMT joints were adopted as failure criteria for interface failure prediction. The equivalent plastic strain in the weld metal, HAZ and base metal of aluminum side of the CMT brazed joints was used as a criterion for failure prediction occurred on the Fusion Line. The shear strength of CMT joints and the two failure modes can be accurately estimated by the developed numerical model.
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investigation on interface failure and shear strength of cmt brazed lap joint of dissimilar materials
Advanced Materials Research, 2012Co-Authors: Jian Lin, Yongping Lei, Nin Shu, Hidekazu MurakawaAbstract:In order to save fuel consumption by reducing the weight of automobile body, the use of aluminum alloys has a great advantage. However, how to join aluminum alloys with steels becomes a big problem in the assembly Lines. Cold metal transfer (CMT) is a promising joining process for steel/Al dissimilar materials. To evaluate the shear strength and to investigate the failure modes of CMT brazed lap joints of dissimilar materials, both experimental observation and numerical simulation are performed. A numerical model for the failure criteria of the interface layer failure between steel and aluminum is developed. The interface layer of CMT brazed lap joint can be modeled by the interface element. The failure stress and failure energy at the interface element are proposed as the failure criteria for the prediction of shear strength of CMT lap joints. If steel sheet thickness becomes thicker, stress distribution and concentration at interface layer elements have some change and shear strength at the interface layer can be improved. Then the failure occurring at the interface element may transfer to the Fusion Line at the side of the aluminum alloy sheet.
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investigation of interface layer failure and shear strength of cmt brazed lap joints in dissimilar materials
Transactions of JWRI, 2011Co-Authors: Jian Lin, Yongping Lei, Hidekazu MurakawaAbstract:In order to save fuel consumption by reducing the weight of automobile body, the use of aluminum alloys has a great advantage. However, how to join aluminum alloys with steels becomes a big problem in the assembly Lines. Cold metal transfer (CMT) is a promising joining process for steel/Al dissimilar materials. To evaluate the shear strength and to investigate the failure modes of CMT brazed lap joints of dissimilar materials, both experimental observation and numerical simulation are performed. A numerical model for the interface layer and for the failure criteria of the interface layer between steel and aluminum is developed. The interface layer of CMT brazed lap joint can be modeled by the interface element. The failure stress and failure energy at the interface element are proposed as the failure criteria for the prediction of shear strength of CMT lap joints. If steel sheet thickness becomes thicker, stress distribution and concentration at interface layer elements have some change and shear strength at the interface layer can be improved. Then the failure occurring at the interface element may transfer to the Fusion Line at the side of the aluminum alloy sheet.
Tetsuo Shoji - One of the best experts on this subject based on the ideXlab platform.
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characterization of microstructure local deformation and microchemistry in alloy 600 heat affected zone and stress corrosion cracking in high temperature water
Corrosion Science, 2012Co-Authors: Zhanpeng Lu, Tetsuo Shoji, Seiya Yamazaki, Kazuhiro OgawaAbstract:Abstract With increasing the distance from the weld Fusion Line in an Alloy 600 heat-affected zone, kernel average misorientation decreases and the fraction of Σ3 boundaries increases. Cr 7 C 3 carbides mainly precipitate at random high angle boundaries. Chromium depletion and segregation of boron and phosphorous at grain boundaries are observed. Alloy 600 heat-affected zone specimens exhibit higher intergranular stress corrosion cracking growth rates than that in the base metal in simulated pressurized water reactor water environments. Crack growth rate is enhanced by strain hardening and by increasing temperature. The role of stress on interface oxidation kinetics is analyzed.
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synergistic effects of local strain hardening and dissolved oxygen on stress corrosion cracking of 316ng weld heat affected zones in simulated bwr environments
Journal of Nuclear Materials, 2012Co-Authors: Tetsuo Shoji, Yoichi Takeda, Fanjiang Meng, He Xue, Koji NegishiAbstract:Abstract Stress corrosion cracking growth during long-term test in high temperature water was monitored in two 316NG weld heat-affected zones representing highly hardened and medially hardened regions. Cracking near the weld Fusion Line exhibited both macroscopic bifurcation and extensive microscopic branching, which was faster than that in the medially hardened region where crack kinking was observed. There is an interaction between material hardening and dissolved oxygen on crack growth. The effect of a single overloading on crack growth in 316NG heat-affected zones is less significant than that in a cold worked 316NG stainless steel.
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characterization of microstructure and local deformation in 316ng weld heat affected zone and stress corrosion cracking in high temperature water
Corrosion Science, 2011Co-Authors: Tetsuo Shoji, Yoichi Takeda, Fanjiang Meng, He Xue, Yubing Qiu, Koji NegishiAbstract:Abstract Microstructure and local deformation in 316NG weld heat-affected zones were measured by electron-back scattering diffraction and hardness measurements. With increasing the distance from the Fusion Line, kernel average misorientation decreases and the fraction of Σ3 boundaries increases. Stress corrosion cracking growth rates in high temperature water were measured at different locations in the heat-affected zones that correspond to different levels of strain-hardening represented by kernel average misorientation and hardness distribution. Intergranular cracking along random boundaries as well as extensive intergranular crack branching is observed in the heat-affected zone near the weld Fusion Line.
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environmentally assisted cracking behaviour in the transition region of an alloy182 sa 508 cl 2 dissimilar metal weld joint in simulated boiling water reactor normal water chemistry environment
Journal of Nuclear Materials, 2008Co-Authors: H P Seifert, Qunjia Peng, Stefan Ritter, Tetsuo Shoji, Yoichi Takeda, Zhanpeng LuAbstract:Abstract The stress corrosion cracking (SCC) and corrosion fatigue behaviour perpendicular and parallel to the Fusion Line in the transition region between the Alloy 182 Nickel-base weld metal and the adjacent SA 508 Cl.2 low-alloy reactor pressure vessel (RPV) steel of a simulated dissimilar metal weld joint was investigated under boiling water reactor normal water chemistry conditions. A special emphasis was placed to the question whether a fast growing interdendritic SCC crack in the highly susceptible Alloy 182 weld metal can easily cross the Fusion Line and significantly propagate into the adjacent low-alloy RPV steel. Cessation of interdendritic SCC crack growth was observed in high-purity or sulphate-containing oxygenated water under constant or periodical partial unloading conditions for those parts of the crack front, which reached the Fusion Line. In chloride containing water, on the other hand, the interdendritic SCC crack in the Alloy 182 weld metal very easily crossed the Fusion Line and further propagated with a very high rate as a transgranular crack into the heat-affected zone and base metal of the adjacent low-alloy steel. The observed SCC cracking behaviour at the interface correlates excellently with the field experience of such dissimilar metal weld joints, where SCC cracking was usually confined to the Alloy 182 weld metal.
Shaogang Wang - One of the best experts on this subject based on the ideXlab platform.
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influence of post weld heat treatment on microstructure and mechanical properties of laser beam welded 2195 al li alloy
Materials Research Express, 2019Co-Authors: Shaogang Wang, Li ZhaoAbstract:2195 Al–Li alloy is welded by using laser beam welding (LBW). Subsequently, the welded joints are treated by solution treatment at 520 °C for 1 h, then aging treatments with different procedures. The influence of post-weld heat treatment (PWHT) on microstructure and mechanical properties of the welded joint is systematically investigated. Optical microscope (OM), scanning electron microscopy (SEM) combined with energy dispersive spectroscopy (EDS), transmission electron microscope (TEM), and x-ray diffractometer (XRD) are used to characterize the microstructure of joints respectively. The tensile strength and microhardness of welded joints before and after PWHT are evaluated respectively. Results show that, after post-weld double aging treatment (HT3), the tensile strength of welded joint is 485.2 MPa, which is 89.03% of that of base metal. Microstructural analysis indicates that the fine equiaxed grain zone (EQZ) near Fusion Line disappears after HT3. The precipitation of strengthening phases such as T1(Al2CuLi) phase is promoted by PWHT both near grain boundaries and in Al matrix. Moreover, the microstructure of weldment is refined after HT3, thus the ductility of welded joint is improved to a certain extent.
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characterization of microstructure mechanical properties and corrosion resistance of dissimilar welded joint between 2205 duplex stainless steel and 16mnr
Materials & Design, 2011Co-Authors: Shaogang WangAbstract:The joint of dissimilar metals between 2205 duplex stainless steel and 16MnR low alloy high strength steel are welded by tungsten inert gas arc welding (GTAW) and shielded metal arc welding (SMAW) respectively. The microstructures of welded joints are investigated using scanning electron microscope, optical microscope and transmission electron microscopy respectively. The relationship between mechanical properties, corrosion resistance and microstructure of welded joints is evaluated. Results indicate that there are a decarburized layer and an unmixed zone close to the Fusion Line. It is also indicated that, austenite and acicular ferrite structures distribute uniformly in the weld metal, which is advantageous for better toughness and ductility of joints. Mechanical properties of joints welded by the two kinds of welding technology are satisfied. However, the corrosion resistance of the weldment produced by GTAW is superior to that by SMAW in chloride solution. Based on the present work, it is concluded that GTAW is the suitable welding procedure for joining dissimilar metals between 2205 duplex stainless steel and 16MnR.
Jian Lin - One of the best experts on this subject based on the ideXlab platform.
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shear strength of cmt brazed lap joints between aluminum and zinc coated steel
Journal of Materials Processing Technology, 2013Co-Authors: Jian Lin, Yongping Lei, Hidekazu MurakawaAbstract:Abstract Higher shear strength and Fusion Line failure were measured in CMT brazed lap joint of aluminum alloy 6061 and zinc coated steels with high strength (DP600) or thick plate (1.2 mm). Lower shear strength and interface failure were observed only if aluminum was brazed with low strength (270 MPa) and thin steel sheet (0.7 mm). A numerical model was developed for the prediction of shear strength and failure modes of the CMT lap joints. The maximum principle stress and deformation energy at the interface layer of the CMT joints were adopted as failure criteria for interface failure prediction. The equivalent plastic strain in the weld metal, HAZ and base metal of aluminum side of the CMT brazed joints was used as a criterion for failure prediction occurred on the Fusion Line. The shear strength of CMT joints and the two failure modes can be accurately estimated by the developed numerical model.
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investigation on interface failure and shear strength of cmt brazed lap joint of dissimilar materials
Advanced Materials Research, 2012Co-Authors: Jian Lin, Yongping Lei, Nin Shu, Hidekazu MurakawaAbstract:In order to save fuel consumption by reducing the weight of automobile body, the use of aluminum alloys has a great advantage. However, how to join aluminum alloys with steels becomes a big problem in the assembly Lines. Cold metal transfer (CMT) is a promising joining process for steel/Al dissimilar materials. To evaluate the shear strength and to investigate the failure modes of CMT brazed lap joints of dissimilar materials, both experimental observation and numerical simulation are performed. A numerical model for the failure criteria of the interface layer failure between steel and aluminum is developed. The interface layer of CMT brazed lap joint can be modeled by the interface element. The failure stress and failure energy at the interface element are proposed as the failure criteria for the prediction of shear strength of CMT lap joints. If steel sheet thickness becomes thicker, stress distribution and concentration at interface layer elements have some change and shear strength at the interface layer can be improved. Then the failure occurring at the interface element may transfer to the Fusion Line at the side of the aluminum alloy sheet.
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investigation of interface layer failure and shear strength of cmt brazed lap joints in dissimilar materials
Transactions of JWRI, 2011Co-Authors: Jian Lin, Yongping Lei, Hidekazu MurakawaAbstract:In order to save fuel consumption by reducing the weight of automobile body, the use of aluminum alloys has a great advantage. However, how to join aluminum alloys with steels becomes a big problem in the assembly Lines. Cold metal transfer (CMT) is a promising joining process for steel/Al dissimilar materials. To evaluate the shear strength and to investigate the failure modes of CMT brazed lap joints of dissimilar materials, both experimental observation and numerical simulation are performed. A numerical model for the interface layer and for the failure criteria of the interface layer between steel and aluminum is developed. The interface layer of CMT brazed lap joint can be modeled by the interface element. The failure stress and failure energy at the interface element are proposed as the failure criteria for the prediction of shear strength of CMT lap joints. If steel sheet thickness becomes thicker, stress distribution and concentration at interface layer elements have some change and shear strength at the interface layer can be improved. Then the failure occurring at the interface element may transfer to the Fusion Line at the side of the aluminum alloy sheet.
Koji Negishi - One of the best experts on this subject based on the ideXlab platform.
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synergistic effects of local strain hardening and dissolved oxygen on stress corrosion cracking of 316ng weld heat affected zones in simulated bwr environments
Journal of Nuclear Materials, 2012Co-Authors: Tetsuo Shoji, Yoichi Takeda, Fanjiang Meng, He Xue, Koji NegishiAbstract:Abstract Stress corrosion cracking growth during long-term test in high temperature water was monitored in two 316NG weld heat-affected zones representing highly hardened and medially hardened regions. Cracking near the weld Fusion Line exhibited both macroscopic bifurcation and extensive microscopic branching, which was faster than that in the medially hardened region where crack kinking was observed. There is an interaction between material hardening and dissolved oxygen on crack growth. The effect of a single overloading on crack growth in 316NG heat-affected zones is less significant than that in a cold worked 316NG stainless steel.
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characterization of microstructure and local deformation in 316ng weld heat affected zone and stress corrosion cracking in high temperature water
Corrosion Science, 2011Co-Authors: Tetsuo Shoji, Yoichi Takeda, Fanjiang Meng, He Xue, Yubing Qiu, Koji NegishiAbstract:Abstract Microstructure and local deformation in 316NG weld heat-affected zones were measured by electron-back scattering diffraction and hardness measurements. With increasing the distance from the Fusion Line, kernel average misorientation decreases and the fraction of Σ3 boundaries increases. Stress corrosion cracking growth rates in high temperature water were measured at different locations in the heat-affected zones that correspond to different levels of strain-hardening represented by kernel average misorientation and hardness distribution. Intergranular cracking along random boundaries as well as extensive intergranular crack branching is observed in the heat-affected zone near the weld Fusion Line.
