結晶塑性Phase-Fieldモデルの構築と塑性変形を伴う微視組織形成過程のシミュレーション

抄録

In this study, a new crystal plasticity phase-field model is developed by coupling the phase-field microelasticity theory and the crystal plasticity theory. We first conduct the simulation of uniaxial tensile loading of a single crystal and confirm the developed model can describe the elastic and plastic deformation behaviors depending on crystal orientation. Then, the present model is applied to the simulation of the growth of single and multiple precipitates with dilatational transformation strain. The simulation results show that the high stress region near the interface migrates with the growth of the precipitates. In the growth of precipitates with plastic deformation, the high stress near the interface decreases by the plastic deformation. Furthermore, it is revealed that the plastic deformation concentrates along the direction that shear stress on the slip plane becomes maximum. Thus, the distribution of the plastic strain depends on the crystal orientation of the parent phase. The simulation of the growth of multiple precipitates also demonstrates that the plastic strain produces the residual stress in the final polycrystalline structure. According to these simulation results, the developed phase-field model offers advantage to describe not only the microstructure evolution during the phase transformation, but also the elastic and plastic deformation behaviors on the basis of the crystal plasticity theory.