Microstructure and properties of the YG8 ESD coating on a cast steel roll

The YG8 electrode was deposited on the surface of a cast steel roll by electro-sparking deposition(ESD) and formed a WC coating.The microstructure and wear resistance of the coating were investigated.The results show that the coating consists of Fe₃W₃C,Co₃W₃C,W₂C and Fe₇W₆ phases,and is metallurgically bonded with the cast steel roll substrate.The Fe₇W₆ and W₂C hard phases dispersedly distributed in the coating with nanosized particles.The average hardness of the coating is 1 331 HV.The coating has improved resistance performance which is 2.3 times higher than the cast steel substrate. The wear mechanism is mainly fatigue wear. Fine hard phases distributed in the coating dispersedly are the main factors leading to the high hardness and wear resistance of the coating.