Antisite Defects of the L12 Structure Determined by the Phase Field Microelasticity Model

A phase field microelasticity simulation is performed to examine the antisite defect of L12-Ni3Al in Ni75Al5.3 V19.7 ternary alloy.Combinimg strain energy with the phase field model leads to an atom conflguration change as time proceeds.For the Ni sublattice,the antisite defect AlNi,the equilibrium occupancy probability (OP) of which declines,precedes NiNi and VNi in reaching equilibrium;subsequently,NiNi and VNi present a phenomenon of symmetrical rise and decline individuaily.Similarly,for the Al sublattice,the antisite defect NiAl,the OP of which eventually rises,takes fewer time steps than AlAl and VAl to attain equilibrium.Thereafter,AlAl rises while VAl declines symmetrically at the axes of the NiAl curve.Furthermore,the OP for the Al sublattice is much more sensitive to strain energy than that for the Ni sublattice.%$Supported by the National Natural Science Foundation of China under Grant Nos 50671084 and 50875217,the Doctoral Foundation of Northwestcrn Polytechnical University under Grant No CX200806,the Specialized Research Fund for the Doctoral Programme of Higher Education of China under Grant No 20070420218,and the Natural Science Foundation of Shaanxi Province.