Influence of coating microstructure on the abrasive wear resistance of WC/Co cermet coatings

Thermally sprayed WC/Co cermet coatings are widely used for their resistanc e to abrasive wear. In this work the influence of the abrasive grain size o n the abrasive wear resistance was investigated for WC/Co coatings sprayed with several processes: APS, high-velocity oxy-fuel(HVOF) and VPS. Results show that the larger the abrasive particle size, the lower the abrasion res istance of the coatings. Moreover, among the thermal spray techniques teste d, HVOF coatings have the best wear resistance while VPS coatings present t he lowest resistance. The role of the coating microstructure and residual s tresses on the wear track and morphologies, as well as the abrasive wear be haviour, are discussed. (C) 2000 Elsevier Science S.A. All rights reserved.