Diffusion Under Temperature Gradient: A Phase-field Model Study
Rashmi R. Mohanty, Jonathan E. Guyer, Yong Ho Sohn
A diffuse interface model was devised and employed to investigate the effect of thermotransport (a.k.a., thermomigration) process in single-phase and multi-phase alloys of a binary system. Simulation results show that an applied temperature gradient can cause significant redistribution of constituent elements and phases in the alloy. The magnitude and the direction of the redistribution depend on the initial composition, the atomic mobility and the heat of transport of the respective elements. In multi-phase alloys, the thermomigration effect can cause the formation of single-element rich phases at the cold and hot ends of the alloy (i.e., demixing).