【摘要】 在改进复合微动试验装置和简化接触界面受力分析的基础上,在倾斜角30°和45°以及不同外加载荷条件下,考察了7075铝合金的复合微动行为及损伤机理,根据不同微动阶段的载荷-位移曲线特征分析了铝合金的微动损伤特性.结果表明,7075铝合金的复合微动行为强烈地依赖于倾斜角度和外加载荷;其复合微动损伤机制主要为剥层机制.更多还原

【Abstract】 A composite fretting tester was modified by installing a specifically designed holder to eliminate the effect of the rotary momentum of the axle on the fretting behavior. Thus the mechanic analysis at the interfaces of the contacting pairs was simplified. The fretting behavior and failure characteristics of 7075Al alloy block against an SAE52100 steel ball were investigated on the modified test rig at block tilt angles of 30° and 45° and loads of 200 N, 400 N, and 800 N. The variations of the veridical force vs. the displacement were recorded and analyzed as the functions of the fretting cycle. The results showed that the loaddisplacement curves and damage processes of the Al alloy subject to composite fretting could be divided into three stages and the damaged surface of the Al alloy was characterized by strong asymmetry, which was attributed to the changes in the contact states and fretting mechanisms at different fretting stages. The Al alloy had composite fretting behavior strongly dependent on the tilt angle and load and was characterized by delamination in fretting against the steel.更多还原