Multiscale Computational Design Optimization of Copper-Strengthened Steel for High Cycle Fatigue

摘要

This research project performed FTMP-based modeling of surface groove formations that ultimately evolve into a crack and the effects of dislocation substructures were considered. Cu-added steels were studied as a model system. As definitive steps toward it, roughly three sub-divided subjects are dealt with: They are (1) effects of Cu addition on the core structure of a screw dislocation in Fe, approached through ab initio-based calculations, (2) Field-theoretical evaluations of dislocation cell structures in terms of flow- evolutionary law (i.e., fluctuations in incompatibility tensor field versus elastic strain energy) and (3) modeling of a slip band (of PSB ladder underlying structure) and attendant crack initiation process.