Even when a macroscopically uniform deformation is applied to a polycrystalline material, the generated microscopic strain distribution will not be uniform due to factors such as the non-uniform grain orientation distribution and grain boundaries. Despite the strong need to accurately measure strain distributions, suitable method is limited. This study proposes an experimental method for estimating strain distributions in polycrystalline materials considering multiple slip systems. Firstly, a polycryst...
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Estimation of Microscopic Deformation Behavior by Digital Image Correlation Method Considering Multiple Slip Systems in Polycrystalline Materials

The SCC susceptibility of the weld metal was evaluated from the maximum depth and number of cracks occurring during the CBB (Creviced Bent Beam) test in high temperature pressurized water using plate specimens cut from shielded metal arc weld metals. When the specimen received a heat treatment consisting of stress relief annealing (SR) for 72 ks at 893 K and subsequent ageing (LTA) for 720 ks at 673 K, however, the significant influences of the increases in C and Nb contents on the SCC susceptibility were...
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Effects of C and Nb Contents on Stress Corrosion Cracking of Shielded Metal Arc Weld Metalfor 600 Type Alloy in High Temperature Pressurized Pure Water

Weld residual stress and distortion affect to fatigue, SCC, static tensile strength, brittle fracture, or other failures in various components. Computational method is useful for evaluating weld residual stress and distortion as well as direct measuring method. Re cently developed methods by the authors for innovative numerical simulation of weld residual stress in various scales and fields are introduced. A lot of applications of the computational approach to weld residual stress evaluation are expected ...
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Innovative Computational Simulation of Weld Residual Stress from Mega- to Micro-Structures

In nuclear power plants, stress corrosion cracking has been observed near the weld zone of the primary loop recirculation pipes made of low-carbon austenitic stainless steel Type 316L. Residual stress is important factor in the occurrence and propagation of SCC. The joining process of pipes usually includes surface machining and welding, and both processes induce residual stresses. In this study, FEM was used to estimate residual stress distributions generated by butt welding and surface machining. In addi...
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Evaluation of Residual Stress Distribution due to Welding and Surface Machining and Crack Growth Behavior

This study shows the effect of the low transformation temperature welding material on residual stress listribution and welding deformation. The expansion due to the transformation fr om austenite to martensite nduces the compressive residual stress around welds. While, in the welding structures, it is important to control the welding deformation and residual stre ss so that they may cause the strength decrease. By using he low temperature transformation welding wire, it may be possible to decrease the weld...
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Numerical simulation of mechanical properities at welding and repairing