采用超音速火焰喷涂技术在结晶器铜板表面制备了高硬度、高耐磨性的Ni60A涂层,研究了真空退火对喷涂层显微组织、显微硬度及高温磨损性能的影响。采用金相显微镜、场发射扫描电镜和X衍射仪分析了喷涂层的显微组织、磨痕形貌和相结构,利用显微硬度计和销盘高温磨损仪检测了喷涂层的硬度和高温耐磨性。结果表明:喷涂层主相为固溶体相γ-(Ni,Fe),此外还有Cr23C6和NixSi相;真空退火后喷涂层显微硬度减小,但涂层组织变得更加致密,涂层500℃高温摩擦系数明显降低,磨损机理均为较轻的黏着磨损。
Ni60A coating with high hardness and high wear resistance on crystallizer copper was prepared by high velocity oxygen fuel(HVOF) spraying technique,the influences of vacuum annealing on microstructure,microhardness and high temperature wear resistance of coating were researched.The microstructure,morphologies of wear traces and phase structure of the spraying layers were analyzed by means of OM,SEM and XRD.The microhardness and high temperature wear resistance were measured with microhardness tester and high temperature wear apparatus,respectively.The results indicate that there are solid-solution phase γ-(Ni,Fe),Cr23C6 and NixSi phase in the coating.The microhardness of coating decreases after vacuum annealing,however,the microstructure of coating becomes denser and the high temperature friction coefficient obviously becomes lower.The wear mechanism is found to be abrasive wear.