Kinetics of diffusion interaction in the Ti-NiCr system layered composites

Abstract

The results of investigation of the diffusion interaction kinetics at the boundary of explosion welded Ti-NiCr system compositions during heat treatment are presented. The structure, chemical and phase composition of the formed diffusion zones are also studied. It is shown that the layered diffusion zone is formed at a temperature below the eutectoid transformation. Diffusion zone consists of solid solutions based on Ti2Ni, TiNi, and TiNi3 intermetallic compounds, as well as chromium-based solid solution inclusions along the boundary with the NiCr alloy. An increase in temperature above the eutectoid transformation leads to an intensification of the growth of the diffusion zone and the diffusion of nickel into the titanium alloy with the formation of a eutectoid structure in it. The use of alloyed titanium alloys instead of commercially pure titanium does not affect the phase composition of the formed diffusion zones, but slows down the diffusion processes.