| Title |
Corrosion Behavior of Thermally Sprayed WC Based Cermet Coatings in Acidic Solution |
| Authors |
조재억(J. E. Cho); 황순영(S. Y. Hwang); 김규영(K. Y. Kim) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
WC cermet coating; HVOF; Corrosion; Wear |
| Abstract |
A study was made to investigate the corrosion and corrosion-wear performances in strong acid (5 wt% H₂SO_(4)) solution for the high-velocity oxygen-fuel (HVOF) sprayed coatings of tungsten carbide (WC) cermets. Four different alloy compositions were used as WC cermet coating materials in this study, and they were WC-Co, WCNi, WC-Co-Cr and WC-CrC-Ni. The immersion test and electrochemical test showed that galvanic corrosion occurred between WC particle and binder metal in the coating layer and general corrosion occurred on metallic binder for non-Cr added WC-Co and WC-Ni coatings. The best anti-corrosion properties were observed in the metallic Cr containing WC-Co-Cr layer, which was presumably due to the formation of beneficial chromium oxide on the coating surface. It was found that the corrosion resistance of WC cermet coatings was dependent on the compositions of binder metals as well as the micro-crack ratio of coated layer. (Received June 12, 2004) |