【摘要】 采用激光熔覆技术在304L不锈钢基体表面制备了Co基高温合金涂层,利用金相显微镜、扫描电镜、能谱分析和X射线衍射分析了涂层的显微组织、物相组成以及磨损表面形貌,测试了涂层的室温滑动摩擦磨损性能。结果表明:激光熔覆Co基合金涂层从底部到表层依次为"胞状晶—粗大枝晶—细小树枝晶"组织,主要由γ-Co固溶体、Fe₂Mo相及Co₇Mo₆相组成,涂层平均硬度约为630 HV,是304L不锈钢基体的3倍,室温摩擦磨损性能是304L不锈钢基体的1～1.5倍。由于难溶元素Mo的固溶强化及Fe₂Mo及Co₇Mo₆硬质相的弥散强化使涂层具有较好的耐磨性能。更多还原

【Abstract】 Co-based superalloy coating was prepared on the 304 stainless steel surface by laser cladding.The microstructure,phase constitutes and worn surface morphology of the coating were characterized by optical microscope,scanning electron microscope（SEM） with energy dispersive spectrum（EDS） and X-ray diffraction（XRD）.The ambient temperature sliding friction and wear property of the coating was also tested.The experiments results showed that:the microstructures of the Co-based superalloy coating are"cellular crystal- coarse dendrite - tiny dendrite"in turn from bottom to surface,which consists ofγ-Co solid solution,Fe₂Mo and Co₇Mo₆.The average micro-hardness of the laser cladding is 632 HV,which is 3 times compared to that of 304 stainless steel matrix.The ambient temperature sliding friction and wear property of the laser cladding is about 1～1.5 times in contrast to that of 304 stainless steel matrix.The better wear resistance of the coating is contributed to solution strengthening of Mo,as well as dispersion strengthening of Fe₂Mo and Co₇Mo₆ hard phases.更多还原