On the mechanism of chromium-nickel two-phase alloy strengthening and fracture

Abstract

The mechanism of strengthening of a two-phase chromium-nickel alloy 65Cr-(31-35)Ni–Ti–V–W depends on the heat treatment mode: the lattice periods of the α-phase (alloy matrix is a solid solution of Ni in Cr) in the hardened and equilibrium conditions are almost the same; level of strength and ductility properties of alloy determines dispersion and amount of γ-soft nuclei released during heat treatment (solid solution of Cr in Ni), its hardness is less than that of α-phase. Quenching from single-phase area from 1250°C and tempering at 800−900°C provides a higher strength than annealed alloy and increases the start temperature of high temperature failure. The nature of the destruction depends on the temperature. The influence of γ-phase is manifested more significantly at temperatures below equicohesive.