采用新型扭动微动试验机在法向载荷为50、80和110 N及角位移幅值为0.3°~10°的条件下进行TA2和TC4合金与ZrO2对磨球的扭动微动试验。在摩擦动力学行为研究的基础上,结合磨痕形貌微观分析,考察TA2和TC4合金的扭动微动磨损特性。结果表明:可用摩擦扭矩—角位移曲线和摩擦扭矩时变曲线表征合金的扭动微动行为,获得了TA2和TC4合金的扭动微动运行工况微动图,TA2合金的混合区较TC4合金的宽。摩擦扭矩随法向载荷和角位移幅值的增加而增加,在相同试验条件下,TA2合金的摩擦扭矩始终大于TC4合金的。在部分滑移区,损伤轻微;在混合区和滑移区,损伤加剧,扭动微动摩擦磨损机制主要为磨粒磨损、氧化磨损和剥落。
The torsional fretting tests of alloys TA2 and TC4 flats against ZrO2 ceramic balls were carried out on a new torsional fretting tester under various angular displacement amplitudes ranging from 0.3° to 10° and imposed normal loads of 50,80 and 110 N.Based on the analysis of the frictional kinetics of the torsional fretting wear and combined with the micro-examinations,the damage characteristics of alloys TC4 and TA2 were also discussed.The results indicate that the behaviors of torsional fretting can be characterized by the curves of friction torque-angular displacement(T-θ) and friction torque curves.Running condition fretting maps of torsional fretting wear for alloys TA2 and TC4 can be set up.The mixed fretting regime of alloy TA2 is wider than that of alloy TC4.The friction torques increase with the increase of the normal loads and angular displacement amplitudes,and alloy TA2 always presents higher friction torques than that of alloy TC4.In the partial slip regime,the damage of torsional fretting wear is slight.In the mixed fretting regime and slip regime,the damage adds,the wear mechanisms of torsional fretting of alloys TC4 and TA2 are mainly abrasive wear,oxidative wear and delamination.