Atomic scale computer simulation for early precipitation process of Ni₇₅Al₆V₁₉ alloy

The atomic scale computer simulation for the initial precipitation mechanism of Ni₇₅Al₆V₁₉ alloy was carried out for the first time by employing the microscopic diffusion equation. The initial precipitation process was investigated through simulating the atomic pictures and calculating the order parameters of the two kinds of ordered phases. Simulation results show that the γ′ ordered phase precipitated earlier than the θ ordered phase by congruent ordering + spinodal decomposition mechanism and thus produced a nonstoichiometric γ′ single ordered phase. Then, the nonstoichiometric θ phase precipitated by a non-classical nucleation and growth mechanism at the APBS of the γ′ phase.