Effect of technological parameters of gas-dynamic deposition on structural-phase transformations in “brass” type coating

Abstract

The results of effect of deposition temperature and the overlap coefficient on the formation of the phase composition of coating based on Cu, Zn and Al2O3 particles mixture applied by cold gas-dynamic deposition are presented. Using X-ray diffraction and X-ray spectral analysis, it is shown that when using the 55 % overlap coefficient electron-type compound based on CuZn3 (ε-phase) is formed in the coating, the mass fraction of which increases to 11.4 % with increase in the deposition temperature. Deposition with 64 % overlap coefficient is accompanied by the formation not only of the ε-phase, but of electron-type compound based on Cu5Zn8 (γ-phase), the mass fraction of which increases to 33 % at temperature of 450 °C. In the process of coating deposition, the predominant diffusion copper into zinc takes place; the calculations show high value of the diffusion coefficient copper — 1,56•10–13 m2 /s.