INTERFACE STRUCTURES OF HIGH-VELOCITY OXY-FUEL SPRAYED WC-CO COATING ON A COPPER SUBSTRATE

Microstructures developing at the interface of a high velocity oxy-fue l (HVOF) sprayed WC-Co coating onto a copper substrate, have been stud ied by preparing thin foils from the interfacial region and examining them using transmission electron microscopy. Two types of substrate su rfaces have been considered: smooth and grit blasted, Modelling of the development of the interface structure has also been undertaken. Both experimental and theoretical results, which agree well, show that the interface structure depends significantly on the morphology of the su bstrate surface. The results obtained enable new views to be put forwa rd on the factors leading to the adhesion between a coating and a subs trate material. (C) 1997 Elsevier Science S.A.