The Influence of Powder Property on WC Cermet Cold Spraying

From the appearance of HVOF thermal spray system on 1980s, WC cermet coatings have been used as an antiwear coating in many industrial manufacturing. Recently, WC cermet spray materials were applied to new thermal spray method 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 metal 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, Ni or Fe powders were sprayed by Cold Spray to investigate the influence of binder metal for spray efficiency and coating property. In addition, the in fluence of CrC which is hard ceramic particle other than WC was investigated by WC-CrC-Fe or Ni chemical component.

It is cleared that Ni and Fe were superior to Co in spray efficiency and coating property.WC-CrC-Fe or Ni are superior to WC-Fe or Ni in spray efficiency and coating property. The detail of above results was under investigation, however, powder property such as metal binder and ceramics type is expected to be an important factor for WC cermet cold spraying.