The analysis of possible application of different working gases in cold gas spray method: dynamics and temperatures of particles

Abstract : The paper analyzes the possibility of application of different working gases and their mixtures in cold gas spraying method (CGSM). The gases such as: (i) H2O vapors; (ii) CO2 ; and (iii) Ar were considered. On the other hand, the analysis included the gas mixtures of Ar, CO2 and N2 with H2O vapor. The temperature of analyzed gases was supposed to be T=800 K and its pressure P=2 MPa which are the typical values in CGSM. The calculation of the profiles along the convergent-divergent nozzle of gas and particle velocity was carried out with the use of Fluent software. The velocity profiles of all analyzed gases were compared to that of the standard gas in CGSM, nitrogen flowing in the same conditions. Finally, the velocities and temperatures of copper particles having diameters 20 and 50 μm in the tested gases flows were calculated and compared to that reached in nitrogen in similar conditions. The difference in temperatures and velocities were explained by sonic velocities, viscosities and thermal conductivities of selected gases.