不同载荷下钛合金激光熔覆Ni60/h-BN自润滑耐磨复合涂层的摩擦学性能  

Effect of Normal Load on Tribological Properties of Ni60 / h-BN Self-Lubricating Anti-Wear Composite Coating on Ti6Al4V Alloy by Laser Cladding

作　　者：任佳[1] 刘秀波[1,2] 余鹏程[1] 陆小龙[1] 陈瑶[1] 石皋莲[3] 吴少华[3] 徐东[4] 

机构地区：[1]苏州大学机电工程学院,江苏苏州215006 [2]中科院兰州化学物理研究所固体润滑国家重点实验室,甘肃兰州730000 [3]苏州工业职业技术学院,江苏苏州215104 [4]江苏大学材料科学与工程学院,江苏镇江212013

出　　处：《摩擦学学报》2015年第4期407-414,共8页Tribology

基　　金：江苏省自然科学基金(BK20141194;BK20131155);江苏省材料摩擦学重点实验室开放基金(Kjsmcx201301);清华大学摩擦学国家重点实验室开放基金(SKLTKF13B08)资助~~

摘　　要：为提高钛合金的摩擦学性能,以金属陶瓷Ni60和固体润滑剂h-BN复合合金粉末为原料,采用激光熔覆技术在钛合金表面制备出了以硬质Ti C、Ti B2、Cr B等为耐磨增强相、以h-BN为固体润滑相的自润滑耐磨复合涂层.采用X射线衍射(XRD)、扫描电镜(SEM)和能谱仪(EDS)分析了涂层的显微组织结构及物相;在室温条件下分别在不同载荷(2、5和8 N)下以Si3N4陶瓷球为对偶件测试了复合涂层与基体的干滑动磨损性能,并分析了其磨损机理.结果表明:复合涂层的平均硬度为HV0.21 013.75,约是基体(HV0.2360)的3倍,在所有试验载荷下,复合涂层的摩擦系数和磨损率均比基体的低.随着载荷的增加,涂层的摩擦系数和磨损率均先减小后升高,说明涂层在5 N载荷下显示出最好的自润滑和耐磨性能.To enhance the tribological properties of Ti6Al4V alloy, self - lubricating anti - wear composite coating reinforced with hard TiC, TiB2, CrB and self - lubricating h - BN were fabricated by laser cladding. The phase compositions and micro structures were investigated by X -ray diffractometer （XRD）, scanning electron microscope （SEM） and energy dispersive spectrometer （EDS） ,respectively. Sliding wear tests of the composite coating and substrate were conducted at 2,5 and 8 N,respectively,with the Si3N4ceramic ball as the counter- body, and the corresponding wear mechanisms are discussed. Results indicate that the mean microhardness of the composite coating （HV021 013.75 ） was about 2 times higher than that of substrate （ HVo 2360）. In all normal loads, both friction coefficient and wear rate of the composite coating were lower than that of the substrate. With the increasing of normal load, both friction coefficient and wear rate of the composite coating decreased firstly and then increased. It is demonstrated that the tribological properties of the composite coating showed the best at 5 N.

关 键 词：固体润滑 耐磨复合涂层 载荷 钛合金 

分 类 号：TG125.9[金属学及工艺—金属学] TG174.44