Effect of duration and temperature of spraying on structure and phase composition of copper-zinc coating of "brass" type

The results of the study of the effect of temperature and displacement of the spray nozzle on structural and phase transformations in a "brass" type coating applied by cold gas dynamic spraying using a mixture of Cu, Zn and Al2O3 particles are presented. X-ray diffraction analysis revealed the formation of phases inherent in brass, namely, an electron-type solid solution based on CuZn3 (ε-phase), the mass fraction of which increases with an increase in temperature from 270 to 540° from 5.3 to 15.6 %. It is shown that when the nozzle is displaced by 2 mm, the additional effect of the solid particle flow is accompanied by the formation of electron-type solid solutions based on Cu5Zn8 (γ-phase) and Cu Zn (β′-phase) with a mass fraction of up to 17 and 1 %, which is associated with the deformation of metals. At the minimum sputtering temperature, boundary diffusion has a significant effect on structural and phase transformations due to the magnitude of the OCR, the size of which for copper does not exceed 21.4 nm when the nozzle is displaced by 3 mm. The magnitude of microdeformations of the transformation products ε-, γ-, and β′-phases is up to 0.24, 0.304 and 0.207 %, respectively, which is associated with transformations in the solid phase.