Improvement of microstructure and property of cold-sprayed Cu–4 at.%Cr–2 at.%Nb alloy by heat treatment

The effect of vacuum heat treatment on the microstructure and microhardness of the cold-sprayed Cu–4 at.%Cr–2 at.%Nb alloy was investigated. After heat treatment, a Cr2Nb phase formed in the gas-atomized powder was uniformly distributed in the matrix. Minimal grain growth of the Cr2Nb phase was observed accompanying the healing-up of the incomplete interfaces between the deposited particles at the elevated treatment temperatures. The microstructure and microhardness of the annealed cold-sprayed Cu–4 at.%Cr–2 at.%Nb alloy were comparable with those of the deposits fabricated by vacuum plasma spraying, which makes it a promising material for regeneratively cooled rocket engine applications.