摘要
由化学镀得到的聚四氟乙稀、石墨、氟化石墨、硫化钼及氟化钙粒子等与镍磷一起沉积的五类自润滑复合镀层。在环块试验机及销盘试验机上研究了其摩擦磨损特性。得出其摩擦系数与抗磨性、试验负荷、粒子含量和镀层的热处理与否有关。与淬火GCr15和氮化过的钢相比,自润滑复合镀层具有低的摩擦系数,比之纯Hi-p镀层其摩擦系数也较低。 由AES和SEM对磨损表面进行分析,当表面的Ni-p逐步磨去时,固相润滑粒子逐步暴露。对细粒子来说(如小于2μm的PTFE)能在对磨件表面形成转移膜,降低摩擦系数,其磨损率略有提高。但如粒子过大(如大于2μm的石墨)则石墨粒子压延并抛光,或碎裂脱落,也能转移并降低摩擦,但使磨损量大为增加。
Five kinds of self- lubricating composite coating have been obtained by electroless deposition, i. e. , PTFE, Graphite, Fluorinated graphite, MoS2and CaF were codeposited in Ni- P matrix. The triobological properties of the coatings were tested on ring- on-block and pin-on-disk machines. It was found that their friction coefficients and wear resistances vary with load, partical content and heat-treatment. Comparing with Ni -Pcoating, nitriding layer of steel, and quenched steel GCr15, self- lubricating compostie coatings possess lower friction coefficient.The worn surfaces were analyzed by AES and SEM. It was observed that as the surface was slowly worn away, more solid lubricant particles in the matrix were exposed. Fine particles (as PTFE particles <2μm) came off constantly and formed a transfer film on the surface of the friction couple. Coarse particles (as graphite particles>30μm) shed partly or fragmented and finally transferred to the opposite surface. It was concluded that such transfers can provide continuous and constant supply of solid lubrication , and thus reduce the friction coefficient.
基金
国家教委高等学校博士学科点专项科研基金资助
关键词
化学镀
复合镀层
磨损
摩擦
electroless deposition, composite coating, wear, friction
