Ordering–separation phase transitions in a Co3V alloy

Abstract

The microstructure of the Co₃V alloy formed by heat treatment at various temperatures is studied by transmission electron microscopy. Two ordering–separation phase transitions are revealed at temperatures of 400–450 and 800°C. At the high-temperature phase separation, the microstructure consists of bcc vanadium particles and an fcc solid solution; at the low-temperature phase separation, the microstructure is cellular. In the ordering range, the microstructure consists of chemical compound Co₃V particles chaotically arranged in the solid solution. The structure of the Co₃V alloy is shown not to correspond to the structures indicated in the Co–V phase diagram at any temperatures.