Phase-field simulation of phase separation in Ni75AlxV25-x alloy with elastic stress
(1.陕西省西安市西北工业大学凝固加工国家重点实验室
2.State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China)
2.State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China)
Abstract: The phase separation in Ni75AlxV25？x alloys incorporated with the elastic stress was investigated using the microscopic phase-field model. The final morphology of γ′ and θ is similar in spatial alignment, but the volume fraction of γ′ phase increases and that of θ decreases as the Al concentration increases. For the small elastic interactions of early-stage phase separation, the coarsening of γ′ and θ can be approximated by a linear growth law as predicated by Lifshitz and Slyozov and Wangner (LSW) theory. As the elastic interactions increase at late-stage coarsening, the growth rate decreases, and the growth presents quick increase at early-stage and slows down at late-stage.
Key words: Ni75AlxV25-x; phase separation; elastic stress; microscopic phase-field