The simulation of stress-induced phase transition of L1₀ re-precipitation based on microscopic phase-field model

It is common that the pre-precipitation phase with kinetics advantage is found during non-equilibrium transformation. The continuously changed stress in the transformation increases the complication of precipitation process. The stress induces Ll₀ pre-precipitation phase in Ni₇₅-Al _12.5-V_12.5 alloy is studied by microscope phase-field model in this paper. It is particularly show that Ll₂ phase precipitates directly without stress. There is no Ll₀ phase to be found in the disordered matrix. Oppositely, Ll₀ phase precipitates firstly with stress, and then it turns into Ll₂ phase. When stress is less, either or both above situations are observed. While stress is stronger, a large range of Ll₀ phase precipitates firstly. Then a part of it dissolves. The rest turns into Ll₂ phase. The precipitation of pre-precipitation phase accelerates the precipitation process. The larger the stress and the more Ll₀ phase precipitation, the longer it exists and the shorter the induction period is.