Effects of particle density on depositing properties of WC-17Co by HVOF process

The in-flight and deposition properties of three types of WC-17Co powder with different particle densities during a high-velocity oxygen fuel (HVOF) thermal spray process were investigated. Three types of powder exhibited similar velocity upon impact on the substrate surface. The powder with the lower particle density exhibited a higher temperature upon impingement process, resulting in the generation of a higher flattening ratio. Thus, the coating derived from the powder with the lower particle density possessed superior micro-hardness, porosity and surface roughness. However, the coating with the lowest particle density showed the poorest fracture toughness because of the generation of the largest amount of amorphous phase.