Simulation of Ordered Domain Interfaces Formed between DO22 Phases in Ni-Al-V Alloy Using Microscopic Phase-Field Model

Abstract:

Microscopic phase-field model was used to simulate the ordered domain interfaces formed between DO22 (Ni3V) phases along [100] and [001] direction in Ni-Al-V alloy. The atomic structure of the interface and the composition of alloying elements at the interfaces were investigated using the occupation probability of atoms. The results show that there are three kinds of stable interfaces formed between DO22 phases (Ni3V) along [100] and [001] direction, and all of them can not migrate. The property of interfaces is related to the atomic structure of interfaces. The L12 phases are precipitated at the (002)//(100) interfaces easily, and this kind of interfaces mainly exist at the early period of precipitation, the (002)//(100)·?[100] interface can form a kind of transitional interface at the early period of precipitation, while the {110} twin interface is the most stable and usual interface of the three kinds of interfaces. The elements of alloy have different preferences of segregation and depletion at different boundaries, V is depleted but Ni is segregated at all interfaces; Al is depleted at the (002)//(100)·?[100] interface but segregated at the other interfaces. The degrees of segregation and depletion are different at different interfaces.