| Optimal Design of a Convergent-Barrel Cold Spray Nozzle by Numerical Method | ||
| Prof. Hanlin Liao1, Wen-Ya Li1, Ga Zhang1, Christian Coddet1, Hong-Tao Wang2 and Prof. Chang-Jiu Li2, 1LERMPS, University of Technology Belfort - Montbeliard, Sevenans, Belfort Cedex, 90010, France, 2Welding Research Institute, School of Materials Science and Engineering, Xi’an Jiaotong University, Xianning West Road 28, Xi'an, 710049, China Cold spray is an emerging coating process in recent years. It has attracted worldwide interest for the fast deposition of high-quality metallic coatings. Many investigators have examined this process by both experiment and numerical simulation on the processing parameters, microstructure and corresponding properties of the deposits. However, there are still some underlying problems to be clarified. Therefore, in this paper, the effect of the main factors, involving the nature of accelerating gas and its operating pressure and temperature, and particle size was investigated numerically with a convergent-divergent nozzle. More attention has been paid on the influence of powder carrier gas on the accelerating gas flow and particle accelerating behavior. It was found that the nature of accelerating gas and its operation pressure and temperature, and particle size significantly influenced the particle velocity. Under a certain accelerating gas condition, with increasing both the pressure and temperature of powder carrier gas, the particle velocity has a little increase. With increasing the powder carrier gas temperature, the particle temperature also has a little increase. The experiment with Cu powder sprayed under different gas conditions confirmed the simulation results. This fact means that the optimization of cold spray process could be conducted using the numerical simulation method. | ||