Simulation of Microstructural Evolution Based on the Phase-Field Method and Its Applications to Material Development

The phase-field method has recently been extended and utilized across many fields in materials science. Since this method can systematically incorporate the effect of coherent strain induced by lattice mismatch and applied stress as well as external electric and magnetic fields, it has been applied to many material processes including solidification, solid-state phase transformations and various types of complex microstructure changes. In this paper, firstly the calculation method of phase-field approach is briefly explained. In particular, the basic philosophy of phase-field simulation is mentioned. Secondly, we summarize the recent calculation results of the phase-field simulation of phase transformations in Fe-based alloys and Ni (or Co)-based superalloys. Finally, the image-based calculation of materials properties is explained, where the simulated microstructure image that is the output data of phase-field simulation is employed as a boundary condition for calculating the materials property, and we show the cases of the mechanical property (stress-strain curve), magnetic property (ferromagnetic hysteresis) and electric property (ferroelectric hysteresis) as typical examples of this approach.