Computer simulation of atomic ordering and compositional clustering in the pseudobinary Ni_3Al-Ni_3V system

摘要

The kinetics of diffusional phase transformations in the pseudobinary Ni_3Al-Ni_3V system were studied using a computer simulation technique based on microscope diffusion equations. Our focus is on the initial stages of atomic ordering an compositional clustering process during the phase transformation of an initially homogeneous disordered f.c.c. ternary alloy(Ni_75Al_25-xV_x) into a two-phase mixture of Ll_2 (ni_3Al) and DO_22 (NiV) ordered phases. A thermodynamic model is proposed to describe the phase equi- libria in this pseudobinary system.