Effects of titanium implantation on cavitation erosion of cobalt-based metal-carbide systems

Cavitation erosion tests were performed on unimplanted and titanium-implanted samples of a cobalt-based superalloy and a 6 wt.% Co-WC carbide. Erosion of unimplanted superalloy samples began with crack propagation through the carbides and debonding at the carbide-matrix interfaces, after which material loss from both matrix and carbide phases took place. Implantation of the alloy resulted in diminished carbide-matrix debonding and matrix phase erosion. Consequently, the erosion resistance of the alloy was significantly increased by implantation, as shown by comparison of cumulative mass loss data for unimplanted and implanted samples. Implantation also produced an improvement in the erosion resistance of the cemented carbide material, again because of increased durability of the matrix phase. (orig.)