Mechanical properties of WC/Co coatings prepared by cold spraying

Abstract

Microstructure, hardness and wear resistance of WC/Co coatings prepared by cold spraying and influence of powder properties, such as powder size, WC particle size and cobalt content, on those properties have been investigated in this study. Both smaller WC particle and low cobalt content are found to be effective to produce dense, hard and highly wear resistant coating. Smaller powder size is also favorable to make a coating with high mechanical properties. The cold sprayed coating using WC(0.2μm)/12% Co with powder size of -20+0 μm has best mechanical properties within this study. This coating has high density compared to conventional HVOF sprayed coatings. Its abrasive wear resistance has been almost comparable to HVOF coating. Strong correlation is also seen between hardness and wear resistance.