铸钢轧辊电火花沉积WC-4Co涂层组织和性能分析

Microstructure and properties of WC-4Co ESD coating of cast steel roll

摘要: 采用新型电火花沉积设备,把陶瓷WC-4Co电极材料沉积在铸钢轧辊材料上,制备了WC-4Co沉积涂层,研究了其微观组织及耐磨性能.结果表明,沉积层主要由Fe₃W₃C,Co₃W₃C,Fe和SiC等相组成;沉积层与基体呈冶金结合,过渡层组织主要是柱状晶结构组织;Fe₃W₃C和Co₃W₃C等硬质相弥散分布于沉积层Fe基体上,部分区域硬质相达到了纳米颗粒尺寸;沉积层硬度的平均硬度为1617.2HV;沉积层较铸钢轧辊的磨损性能提高了2.1倍,沉积层的磨损机理主要是粘着磨损、疲劳磨损、氧化磨损和磨粒磨损的综合作用,细小的弥散分布的硬质相是沉积层硬度及耐磨性提高的主要因素.

Abstract: WC-4Co electrode material is deposited on the surface of cast steel roll by electro-spark deposition(ESD).The microstructure and wear resistance of the coating are investigated.The results show that the coating consists of Fe₃W₃C,Co₃W₃C,Fe and SiC phases,and the coating bonded with cast steel roll substrate is well metallurgical.The phases of Fe₃W₃C and Co₃W₃C distribute dispersedly in the coating with the extra-fine structure.The average hardness of the coating is 1 617.2 HV.The resistance performance of the coating is 2.1 times higher than that of the cast steel substrate.The wear mechanism is adhesion wear,fatigue wear,oxidization wear and abrasive wear,but the main wear mechanism is fatigue wear and abrasive wear.