铸钢表面电火花沉积层摩擦磨损性能  

Wear-resistance of WC-4Co coating on cast steel by electro-spark deposition

作　　者：王建升[1] 卢海霞[1] 阎镇威 李刚[1] 唐明奇[1] 冯在强[1] 

机构地区：[1]华北水利水电大学机械学院,河南郑州450011

出　　处：《材料热处理学报》2015年第1期169-172,共4页Transactions of Materials and Heat Treatment

基　　金：水利部948推广项目(201048)

摘　　要：采用新型电火花沉积设备,把WC-4Co陶瓷硬质合金材料沉积在铸钢材料上,制备了电火花沉积合金涂层,用SEM、XRD等技术研究了沉积层的物相、微观组织结构、元素分布、显微硬度及室温高温耐磨性能及磨损机理。结果表明:沉积层主要由Fe3W3C、Co3W3C和Fe2C等相组成;沉积层与基体呈冶金结合,过渡层出现一些柱状晶和树枝状晶组织结构,沉积层中细小的Fe3W3C和Co3W3C等硬质相颗粒弥散分布于Fe2C基体上。沉积层的平均显微硬度为1803.2 HV;室温下沉积层的耐磨性和300℃高温条件下沉积的耐磨性分别比同样条件下铸钢材料的磨损性能提高了2.5倍和3.4倍;不论室温还是300℃高温条件下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。WC-4Co cemented carbide was deposited on cast steel by electro-spark deposition( ESD). Phase,microstructure,element distribution,microhardness,wear resistance and wear mechanism of the coating were investigated. The results show that the coating consists of Fe3W3 C,Co3W3C and Fe2 C phases. The coating is well metallurgical bonded with the cast steel roll substrate and the transition zone including columnar and dendritic microstructure. The Fe3W3 C and Co3W3 C phases distribute dispersedly in the coating with the extra-fine structure. The average microhardness of the coating is 1803. 2 HV. The coating has better wear resistance which is 2. 5times higher than that of the cast steel substrate at room temperature,and is 3. 4 times higher than that of the cast steel substrate at temperature of 300 ℃. The wear mechanism of the coating is adhesion wear,fatigue wear,oxidization wear and abrasive wear at room temperature or high temperature. These fine and dispersed hard phases can greatly improve the wear-resistance of the coating.

关 键 词：电火花沉积 WC-CO硬质合金 铸钢 耐磨性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]