微孔贯通型高温自润滑金属陶瓷的摩擦磨损性能研究

Study of Tribological Properties of High Temperature Self-lubricating Ceramic with Transfixing Micro-pores

以TiH2和CaCO3为复合造孔剂，以硬质微细颗粒为惰性弥散质点，采用真空烧结法制备出具有贯通型微孔结构的Al2O3-Ni-Cr-Mo-Si-Fe系金属陶瓷烧结体，并在烧结体中浸渍Ag-Cu-Pb-Sn系浸渍型固体润滑剂制备出新型高温扩散自润滑材料．结果表明：该材料具有良好的高温自润滑和耐磨性；在600℃下与不同配对材料进行摩擦磨损试验时，摩擦系数变化范围为0．22—0．29;磨损率变化范围约为（6—7）×10^-15m^3／N·m；润滑膜主要由浸渍在贯通型微孔中的浸渍型固体润滑剂通过微孔向摩擦表面的扩散、并在高温摩擦条件下被软化或熔化而形成．

A new cermet sinter with through micro-porous structure was developed by vacuum liquid phase sintering method, in which Al2O3-Ni-Cr-Mo-Si-Fe powder was used as the basic material, TiH2 and CaCO3 were used as the composite pore-forming materials and horniness grains was used as dispersal particles. The cermet sinter was then infiltrated with Ag-Cu-Pb-Sn at vacuum and formed a new high temperature self-lubricating material. Experiment was carried out at high temperature condition. Worn surface morphologies was observed by SEM. Results show that the cermet sinter infiltrated Ag-Cu-Pb-Sn exhibited good lubricating property and wear resistance. Friction coeffi- cient is about 0.22 -0.29, and wear rate is about（6 -7） ×10^-15 m^3/N· m at 600℃. Lubricating film formed and Ag-Cu-Pb-Sn elements exist in the film. Solid lubricants infiltrated into micro holes and diffused to friction surface. and high temperature due to friction resulted in soften or melt lubricant films.