等离子喷涂TiC-Graphite复合涂层摩擦磨损性能  

Tribological Properties of Plasma Sprayed TiC-Graphite Composite Coatings

作　　者：洪督 牛亚然[1] 李红[2] 钟鑫 郑学斌[1] HONG Du;NIU Yaran;LI Hong;ZHONG Xin;ZHENG Xuebin(Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China;School of Materials Science andEngineering,Shanghai University,Shanghai 200072,China)

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050 [2]上海大学材料科学与工程学院,上海200072

出　　处：《无机材料学报》2022年第6期643-650,共8页Journal of Inorganic Materials

基　　金：国家重点研发计划(2016YFE0111200)。

摘　　要：等离子喷涂TiC涂层具有良好的综合性能,在极端环境能起到较好的耐磨保护作用,而石墨是一种优异的自润滑材料。通过喷雾干燥与真空烧结技术制备不同石墨添加量(1.25%、2.5%、5%和10%,质量分数)的TiC-Graphite球形粉体,并采用大气等离子喷涂技术制备TiC-Graphite复合涂层。对涂层的相组成、显微结构和力学性能进行了表征,并对涂层的摩擦磨损性能进行了比较研究。结果发现,TiC-Graphite涂层主要由TiC和石墨相组成。随石墨添加量增大,TiC-Graphite涂层截面微裂纹增多,表面粗糙度增大,硬度下降。石墨对TiC涂层在高载荷的磨损性能影响更显著。在50 N高载荷条件,随石墨添加量增大,TiC-Graphite涂层磨损率降低后急剧增大,而摩擦系数持续减小。当石墨添加量为2.5%时,涂层获得最低的磨损率为0.67×10^(−5) mm^(3)/(N·m),同时具有较低的摩擦系数(0.35),与不添加石墨的TiC涂层相比,分别降低了72.4%和27.8%。Plasma sprayed TiC coating has now been a frequent choice for wear-resistant applications in extreme environments owing to its good comprehensive performance.Meanwhile,graphite is an excellent self-lubricating material.Here,spherical TiC-Graphite composite powders with different contents of graphite(1.25%,2.5%,5%,and 10%in mass)were fabricated by spray drying and vacuum sintering,and then TiC-Graphite composite coatings were prepared by atmospheric plasma spray(APS)technology.The phase composition,microstructure and mechanical properties of the coatings were characterized,and its tribological performances were evaluated.The results showed that the TiC-Graphite coatings were mainly composed of TiC and graphite phases.With the increase of graphite addition,the micro-cracks in the section and the roughness of the TiC-Graphite coatings increased while the hardness gradually decreased.Compared with low load,graphite had more significant effect on wear performance of the TiC coating under high load.Under the load of 50 N,wear rate of the TiC-Graphite coating first decreased and then increased,but the friction coefficient kept decreasing with the increase of graphite addition.When the graphite addition was 0.25%,the minimum wear rate of 0.67×10^(−5) mm^(3)/(N·m)was obtained,whereas the friction coefficient was 0.35,which were reduced by 72.4%and 27.8%compared with the pure TiC coating,respectively.

关 键 词：TiC-Graphite复合涂层 磨损性能 大气等离子喷涂 显微结构 力学性能 

分 类 号：TQ174[化学工程—陶瓷工业]