Erosion Wear is a main failure mode of materials and equipment and exists in many industrial fields.Thermal sprayed WC-Co cermet coatings have been used widely in these industries because of the coatings excellent erosion wear resistance.The coating microstructures and the erosive wear performance are mainly influenced by WC-Co feedstock material characteristics and the coating deposition methods.Research have shown that the hardness and strength of WC-Co materials increase as the WC particle size reduces; In comparison with conventional WC-Co cermet,nanostructured WC-Co materials possess higher hardness and toughness,more excellent sliding wear resistance and more extensive application potential.HVOF process is more suitable to deposit nanostructured WC-Co coatings than other thermal spraying processes because of the features of high flame velocity,low flame temperature and decrease in WC decarburization of WC-Co feedstock powder during thermal spraying.