Microscopic phase-field model was used to simulate the early precipitation process of Ni

75

Al

6.5

V

18.5

alloy.By analyzing the evolution of atomic image and the atomic occupation probability

the precipitation mechanism and some non-equilibrium phenomena were systematically explored.The result show that transferable interface has a specific atomic transition mode

and the atomic transition presents to some regularity.（100）D∥（200）Land（100）D∥（200）L·1/2[001]before and after the migration

interface structure remains unchanged

and（200）D∥（100）L·1/2[100]

is migrated to form（200）D∥（100）L

alternating between the two.Phase interface migration can induce phase transition L12 to DO22

and Ni atoms at the interface are stepped to the position of the nearest neighbor of Al

and V is migrated to the DO22 domain

while Al is migrated to the outside interface.Interphase interface migration comes by the atomic transition and replacement model

following the shortest path of least resistance and replace mode atomic transition

which means the transformation of L12 phase to DO22 phase mutually following the best thermodynamics and kinetics optimization path.