Abstract
The structural and mechanical properties, in terms of surface roughness, hardness and wear resistance, of WC/12wt%Co coatings are investigated as a function of powder properties, such as powder size and WC grain size, as well as high velocity oxygen-fuel (HVOF) spray conditions. It has been found that the WC/12wt%Co coatings with relatively smoother surface, about 2 µm in average surface roughness (Ra), retaining high wear resistance can be formed by optimizing the powder and spray parameters. Further, we have found that powder size can control the surface roughness over a wide range; from about 2 to 7 µm (about Δ5 µm) in Ra. On the other hand, Ra changed only about Δ1 µm or more when changing spray conditions, such as barrel length and spray distance.