【摘要】 以TiAl合金为基体,添加Ag+ZnO新型复合固体润滑剂,采用放电等离子烧结法(SPS)制备出具有良好摩擦学性能的自润滑复合材料。通过改变工况条件,研究了复合材料在不同温度的摩擦学性能,并探讨了钛铝基自润滑复合材料的磨损机理及其自润滑机理。在干滑动摩擦过程中,试样在不同工况条件下表现出不同的摩擦学行为。在25～800℃下,TiAl-3.5%Ag-6.5%ZnO(T1)和TiAl-5.0%Ag-5.0%ZnO(T2)在不同温度段的摩擦系数与磨损率明显不同,其中T2的摩擦学性能相对更好;钛铝基自润滑复合材料之所以表现出良好的摩擦学性能,主要是因为固体润滑剂Ag和ZnO共同发挥出的协同润滑效果从而提高了复合材料的自润滑性能。摩擦学性能较好的材料,其磨痕表面覆盖一层不同完整度的摩擦层,且当摩擦层越厚时,复合材料的磨痕表面越光滑,其摩擦学性能越好。更多还原

【Abstract】 By adding Ag and ZnO into TiAl matrix,a new type TiAl matrix self-lubricating composite was fabricated successfully by SPS.The tribological properties of the composites under different temperature were studied by changing the working condition.The friction and wear mechanism of TiAl matrix self-lubricating composite material and its self-lubricating mechanism were discussed.In the process of dry sliding friction,the samples exhibit different tribological behaviors under different working conditions.When the temperature rises from room temperature to 800 ℃,the friction coefficient and wear rate of TiAl-3.5%Ag-6.5%ZnO(T1) and TiAl-5.0%Ag-5.0%ZnO(T2) are significantly different,and the tribological properties of T2 is relatively better.TiAl based self-lubricating composites exhibit excellent tribological properties due to the synergistic lubrication effect of solid lubricant Ag and ZnO,which improves the self-lubricating properties of the composites.The wear surface of the material with good tribological properties is covered with a friction layer with different integrity.When the thickness of the friction layer is thicker,the wear surface of the composite is smoother and the tribological properties is better.更多还原