Tribological behavior and mechanisms of graphite/CaF_2/TiC/Ni-base alloy composite coatings  

石墨/CaF_2/TiC协同改善镍基合金喷涂层的摩擦磨损行为与机理(英文)

作　　者：蔡滨[1] 谭业发[1] 何龙[1] 谭华[1] 王小龙[1] 

机构地区：[1]解放军理工大学野战工程学院,南京210007

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第2期392-399,共8页中国有色金属学报（英文版）

摘　　要：In order to reduce the friction coefficients and improve the wear resistance of mechanical parts, which work in the severe friction and wear conditions at heavy loads, the graphite/CaFg/TiC/Ni-base alloy composite coatings were prepared by plasma spray and their tribological behavior and mechanisms were investigated. The results show that the friction coefficients of the composite coatings are in the range of 0.22-0.288, which are reduced by 25.9% to 53% compared with those of the pure Ni-base alloy coatings, and the wear rates of the former are 18.6%-70.1% less than those of the latter. When wear against GCr15 steel balls, a transferred layer mainly composed of ferric oxides, graphite and CaF2 may gradually develop on the worn surface of the composite coatings, which made the friction and wear between GCr15 steel ball and the composite coatings change into that between the former and the transferred layer. So the friction coefficients and the wear lubrication effect of the transferred layer. The main wear layer in friction process. rates of the composite coatings are greatly reduced because of the solid mechanism of the composite coatings is delamination of the transferred为了降低机械零件在强烈摩擦磨损条件下的摩擦因数,提高其耐磨性,制备了等离子喷涂石墨/CaF2/TiC/镍基合金复合涂层,研究其摩擦学行为及机理。结果表明,石墨/CaF2/TiC/镍基合金复合涂层的摩擦因数为0.22-0.288,较纯镍基合金涂层的降低了25.9%-53%,磨损率较之降低18.6%-70.1%。与GCr15钢球对摩时,复合涂层的磨损表面逐渐形成了由铁氧化物、石墨和CaF2组成的转移层,使GCr15钢球与复合涂层的摩擦转变为钢球与转移层的摩擦。由于转移层起到固体润滑作用,复合涂层的摩擦因数和磨损率大幅度降低。复合涂层的主要磨损机理是转移层在载荷的反复作用下而产生的层脱剥落。

关 键 词：plasma spray composite coatings Ni-base alloy GRAPHITE TIC CAF2 TRIBOLOGY 

分 类 号：TH117[机械工程—机械设计及理论]