激光熔覆NiCr/Cr_3C_2-Ag-BaF_2/CaF_2金属基高温自润滑耐磨覆层的组织结构及摩擦学性能  

Microstructure and Tribological Behavior of Laser Cladding NiCr/Cr_3C_2-Ag-BaF_2/CaF_2 Self-lubrication Wear-resistant Metal Matrix Composite Coating

作　　者：俞友军[1,2] 周健松[1] 陈建敏[1] 周惠娣[1] 郭纯[1,2] 

机构地区：[1]中国科学院兰州化学物理研究所固体润滑国家重点试验室 [2]中国科学院研究生院

出　　处：《中国表面工程》2010年第3期64-69,73,共7页China Surface Engineering

基　　金：国家自然科学基金委创新研究群体科学基金(NNSFC;No.50421502);"西部之光"基金项目

摘　　要：利用激光熔覆技术在不锈钢表面制备了NiCr/Cr3C2-Ag-BaF2/CaF2金属基高温自润滑耐磨覆层,用X射线衍射仪分析了复合粉末及其激光熔覆耐磨覆层的物相组成,用扫描电子显微镜分析了耐磨覆层横截面的显微组织结构特征。在干滑动磨损试验条件下测试了覆层的耐磨性能,并用扫描电子显微镜观察和分析了覆层的摩擦磨损机理。试验结果表明,激光熔覆NiCr/Cr3C2-Ag-BaF2/CaF2金属基高温自润滑耐磨覆层,从室温到500℃试验温度范围内表现出了良好的减摩抗磨效果,并且随着温度的升高覆层材料表现出了不同的摩擦磨损机理,从室温到200℃温度范围主要表现为粘着磨损和磨粒磨损共同作用,温度超过200℃后主要表现为塑性变形和轻微的粘着磨损。The self-lubrication wear-resistant NiCr/Cr3C2-Ag-BaF2/CaF2 metal matrix composite coating was fabricated on 1Cr18Ni9Ti stainless steel substrate by means of laser cladding.The phase compositions and cross-sectional microstructures of the coating were analyed by means of scanning electron microscopy and X-ray diffraction.The friction and wear behavior of the composite coating sliding against Si3N4 ceramic ball from ambient to 500 ℃ was evaluated using a ball-on-disc friction and wear tester,and the worn surface morphologies of the composite coating were observed using a scanning electron microscopy.It was found that the laser cladding NiCr/Cr3C2-Ag-BaF2/CaF2 metal matrix composite coating on the stainless steel substrate had good friction-reducing and antiwear abilities at elevated temperatures up to 500 ℃.The laser cladding composite coating was dominated by mixed adhesion and abrasive wear as it slid against the Si3N4 ceramic ball below 200 ℃.With further increase in the test temperature up to 500 ℃,it was characterized by mild adhesive wear and plastic deformation.

关 键 词：激光熔覆 金属基复合覆层 自润滑 摩擦磨损 

分 类 号：TG146[一般工业技术—材料科学与工程] TG115.58[金属学及工艺—金属材料]