The structure and properties of a coating based on a mechanical mixture of Cu and Zn particles deposited on a steel substrate by gas-dynamic spraying are studied. X-ray diffraction and microspectral analysis show a significant effect of the deposition temperature on the content of Cu and Zn in the coating. When the deposition temperature increases from 270 to 450 degrees C, the Zn content increases from 8.15 to 37.6 wt % and the copper content decreases from 91.7 to 62.2 wt %. The results indicate the predominant diffusion of Cu into Zn and the formation of gamma- and epsilon-electron-type Cu5Zn8 and CuZn3 solid solutions the mass fraction of which at a deposition temperature of 450 degrees C reaches 11.2 and 33%, respectively. With increasing deposition temperature, the substructure of the starting components (Cu, Zn) is crushed from 200 to similar to 90 and 64 nm, respectively. The size of the coherent-scattering region in the ge phase with increasing air temperature increases from 70 to 97 nm, and that in the gamma phase decreases from above 200 to 62.0 nm. Estimates show that the coefficient of diffusion of copper into zinc is similar to 1.14 x10(-8) cm(2)/s. The hardness of the deposited Cu-Zn coating reaches 170 HV.
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