Effect of Substrate Hardness and Gas Temperature on Deposition Behavior of Nanostructured WC-23Co Particles in Cold Spraying Process

Nanostructured WC-Co powders were cold sprayed on different substrate materials at different accelerating gas temperatures. Splat morphology and microstructure were examined, showing that the splats are partially embedded in plain carbon and stainless steel substrates with a contour similar to that of the feedstock powder. Gaps and revers were observed around the splats and corrugations or ripples were found on the surface. In contrast, splats on the surface of WC-Co substrates are relatively flat with ejectas on the periphery. A comparison of splats also shows that particle deformation increases with increasing gas temperature and substrate hardness.