(华北水利水电学院 机械学院,郑州 450011)
摘 要: 采用新型电火花设备在铸钢表面制备了YG8涂层,采用SEM、XRD技术研究其微观组织和耐磨性能。结果表明:沉积层主要由Co3W3C、Fe3W3C、Fe3Mo3C、WC1−x和Fe7W6C等相组成;沉积层与基体冶金结合,细晶碳化物相弥散分布在沉积层中,能提高沉积层的硬度,平均硬度为1 896.8HV,比基体硬度提高了5倍;沉积层磨损性能是基体的3.4倍,沉积层磨损机理主要是粘着磨损、颗粒磨损和氧化磨损的综合作用;沉积时骤热骤冷过程中形成的细晶粒硬质相是提高沉积层硬度和耐磨性的主要因素。
关键字: 铸钢0Cr13Ni5Mo;电火花沉积;YG8沉积层;显微组织;耐磨性
(School of Mechanical Engineering, North China University of Water Resource and Electric Power,
Zhengzhou 450011, China)
Abstract:The YG8 electrode coating was deposited on surface of 0Cr13Ni5Mo cast steel by electro-spark deposition (ESD). The microstructure, micro-hardness and wear resistance of the coating were investigated by SEM and XRD. The results show that the coating consists of Co3W3C, Fe3W3C, Fe3Mo3C, WC1−x and Fe7W6C phases, and is bonded metallurgically with that of the 0Cr13Ni5Mo cast steel substrate. The fine-structure grain carbide phases dispersed in the deposited layer increase the micro-hardness,and the average hardness is 1 896.8HV, which is about 5 times higher than that of the 0Cr13Ni5Mo cast steel substrate. The coating improves the wear resistance performance, and the average wear resistance rate is 3.4 times of that of the 0Cr13Ni5Mo cast steel substrate. The wear mechanism is mainly adhesion wear, abrasive wear and oxidization wear. The fine-structure hard phases formed under the condition of fast thermal and rapid cool are the main factors leading to the high hardness and wear resistance of the coating.
Key words: 0Cr13Ni5Mo cast steel; electro-spark deposition (ESD); YG8 coating; microstructure; wear resistance