微視力の概念に基づく多結晶オーステナイト鋼における寸法依存塑性変形挙動の数値シミュレーション

抄録

Steel containing the metastable austenitic phase shows excellent mechanical properties such as strength, ductility and toughness. The transformation-induced plasticity (TRIP) in the steel can optimize these mechanical properties. Since strain-induced martensitic transformation (SIMT) causes TRIP, deep understanding of the continuous development of SIMT is very important to control the mechanical properties by TRIP. In addition, a dislocation attributes to the strain hardening so it is very important to clearly explain its complexity. It is necessary to construct a model on the dislocation deeply related to size effects. In this study, a hardening model and yield conditions for monocrystalline austenitic steel are established based on the notion of microforce. By incorporating the finite element crystal plasticity method, the two-dimensional unit cells of polycrystalline austenitic steel are obtained by Voronoi tessellation, and the deformation behavior and microstructure are simulated computationally.