氮化钛微粉增强镍磷化学复合镀层的组织及其摩擦磨损性能研究

Microstructure and Tribological Behaviour of Electroless Ni-P Plating Reinforced by Fine TiN Powders

利用自蔓延高温合成法得到的氮化钛微粉制备了Ｎｉ－Ｐ－ＴｉＮ化学复合镀层，采用Ｘ射线衍射仪、扫描电子显微镜和电子探针分析了镀层的组织和结构，并在球－块摩擦磨损试验机上对镀层的摩擦学性能进行了研究。结果表明，ＴｉＮ微粉可使Ｎｉ－Ｐ化学镀层的组织明显细化，且能提高镀层的最佳时效硬化温度。随着Ｎｉ－Ｐ－ＴｉＮ化学复合镀层中ＴｉＮ共析量的增加，摩擦系数逐渐降低并趋于稳定，耐磨性则存在一个最佳ＴｉＮ含量；ＴｉＮ微粉在Ｎｉ－Ｐ合金中的牢固镶嵌和ＴｉＮ的自润滑能力，都是使Ｎｉ－Ｐ－ＴｉＮ化学复合镀层具有良好减摩耐磨性能的重要原因。

An electroless Ni-P plating reinforced by ced*fhC Npowders w&s invest*3tC山Thnearspherical particles l)erformed by method of self propergating high temperature synthesis had anarrow size distribution ranged from 0.2 to 1.0μm. The microstructure of the coatings wasdetermined by XRD,EPMA and SEM,and tribological properties by using a ring on block testmachine. The results revealed that as a kind of dispersion phase,TiN particles played a prominentrole in refining microstructure , postponing the optimum aging temperature to a high side andlowering coefficient of friction and wear volume. It was considered that the improved performencesof the coatings might be principlly attributed to the excellent ability of embeding of TiN particles inthe substrate of Ni-P alloy and the ability of self lubrication of TiN its-self.