Abstract
From the appearance of high velocity oxygen fuel (HVOF) thermal spray system on 1980s, WC cermet coatings have been used as an anti-wear coating in many industrial manufacturing. Recently, WC cermet spray materials were applied to new thermal spray methods such as warm spray and cold spray under research phase. In HVOF spraying, WC-Co or WC-Ni series powder are used as standard contents. Ni and Co are binder metals for WC because of good wettability and suitable melting point. On the other hand, warm spray and cold spray are lower temperature process than HVOF. It is considered that any other factors of metal material such as hardness, toughness and crystal phase should be investigated in warm spray and cold spray. In this study, WC with Co or Fe alloy powders were sprayed by cold spray and HVOF to investigate the influence of binder metal for spray efficiency and coating property. It is cleared that Ni and Fe were superior to Co in spray efficiency and coating property in cold spray. The detail of above reason was under investigation, however, plastic deformability of binder metal is expected to be an important factor for WC cermet cold spraying.
