Gas-dynamic spraying. An experimental study of the spraying process

We present results of an experimental study of the specific features of the gas-dynamic formation of coatings from metallic powders ($d_p<$ 50 $\mu$m) on substrates of various materials depending on the particle velocity (200–1200m/sec), the jet temperature (300–700K), and other parameters. Results of a prospecting study of the implementation of the methods of particle acceleration in supersonic (M = 2.0–3.0) rectangular nozzles are described. The rate of bond formation in a cold particle-cold substrate contact occurring in gas-dynamic spraying is estimated within the framework of the concepts applied in analysis of gas-dynamic spraying.