Microscopic Phase-Field Simulation of Atom SubstitutionBehaviour in Ni–Cr–Al Alloy

Abstract

Simulations are performed on atom substitution behaviour inNi75Al25−xCrx alloys based on a microscopicphase-field model at 873 K. The ordering of both the Al and Cr atomstakes place simultaneously, Cr occupies both the Al and Ni sites with apreference for the Al sites, and Cr and Al atoms together occupy theβ -sites, and the complex γ′Ni3(Al1−xCrx) (L12 structure) phases areformed during the precipitation. At the ordering boundary of L12phases, Cr atoms occupy the Al sites, then Ni3Cr phases areformed.