The formation of tribolayers may play significant influences on fretting wear. At elevated temperature, the adhesion among wear debris and the increased diffusion rate facilitate the formation of tribolayers. However, the intensification of oxidation at elevated temperature and the low diffusion rate in oxides may play an adverse role. The present study aims to investigate the role of temperature in tribolayers in fretting wear using a γ-TiAl alloy. Scanning electron microscope, energy dispersive spectrometer, Raman spectrometer, transmission electron microscope and nanoindentation were utilized to investigate the wear debris, tribolayers, and wear scars. The fretting tests showed that, compared with that at room temperature (RT) and 350 °C, significant reduction in wear rate and decrease in the fluctuation of friction coefficient occurred at 550 and 750 °C. It was further revealed that when temperature raised from room temperature (RT) to 750 °C, the oxidation of the wear debris increased slightly and the diffusion coefficients increased prominently, which facilities the formation of well tribo-sintered tribolayers. The well tribo-sintered tribolayers presented homogenous structure, nanocrystalline grains with excellent mechanical properties, and resulted in the improvement in the fretting wear resistance of the γ-TiAl alloy at 550 and 750 °C.

摩擦层的形成可能对微动磨损产生重大影响。在高温下，磨屑之间的粘附和扩散速率的增加有利于摩擦层的形成。然而，高温下氧化的加剧和氧化物中的低扩散速率可能会起到不利的作用。本研究旨在研究摩擦层温度在 γ-TiAl 合金微动磨损中的作用。利用扫描电子显微镜、能谱仪、拉曼光谱仪、透射电子显微镜和纳米压痕仪对磨屑、摩擦层和磨痕进行研究。微动试验表明，与室温和350℃相比，550℃和750℃磨损率显着降低，摩擦系数波动减小。进一步发现，当温度从室温（RT）升高到750℃时，磨屑的氧化略有增加，扩散系数显着增加，有利于形成良好的摩擦烧结摩擦层。良好的摩擦烧结摩擦层呈现均匀的结构、纳米晶粒和优异的力学性能，从而提高了γ-TiAl合金在550和750℃下的耐微动磨损性能。