Phase Field Study for Self-Assemble of the Second Phase Particles in Coherent Phase Transition

We present a phase field model for coherent phase transition and its application to the self-assembled arrangement of second phase particles in coherent phase transition. The model developed here is free from the interface instability due to the contribution of chemical free energy and correctly describes elastically inhomogeneous system. It is observed that coherent misfit strain and anisotropy of elastic constants induce the interface instability that brings about the particle splitting and the self-assembled alignment of second phase particles. Their arrangement to the elastically soft direction occurs only in the system where the elastic contant of the precipitates is larger than that of the matrix phase.