摘要
通过测定工业纯铜(UNS C110)和奥氏体不锈钢(AISI 304)在正交圆柱接触条件下由静止-滑动混合模式向完全滑动模式转变的临界位移振幅(D_(cr))和临界切向力振幅(T_(cr)),研究了正载荷、振动频率及材料性能对微动摩擦接触状态的影响.用试验结果与Mindlin的理论模型比较发现:在一定的低振幅下,接触表面上确有相对静止区域存在,临界位移振幅(D_(cr))正比于正载荷的2/3次方(F_N^(2/3)).这与理论模型相符.但由于理论模型未考虑塑性流变的影响,因此对试验材料来说,理论计算值((?)_(cr))比实测值D_(cr)偏低.偏差的大小,不仅取决于材料的延展性,还与形变硬化及摩擦生热软化的影响有关.所以需要建立包括塑性变形能力参数的理论模型.
The influence of normal load and frequency of vibration on the contact conditions in fretting has been investigated by measurements of critical amplitudes of displacement (D_(cr)) and tangential force (T_(cr)) for transition from mixed stick-slip regime to gross slip regime.Fretting tests were performed with two materials, a pure copper (UNC C110) and an austenitic stainless steel (AISI 304) using a crossed-cylinder geometry. The results were compared with a theoretical model developed by Mindlin. It was found that the contact condition is characterized by partial stick at the interface, if the amplitude is low enough. The critical displacement amplitude D_(cr) is proportional to the two thirds power of F_N, where F_N represents the applied normal force, as predicted by the theoretical model. Plastic flow is not accounted for in the model, D_(cr) is, therefore, underestimated for the test materials. The amount of difference between measured D_(cr) and calculated (?)_(cr) not only depends on the natural ductility of materials but also the strain hardening and the thermal softening effects.
出处
《西安工业学院学报》
1992年第4期1-10,共10页
Journal of Xi'an Institute of Technology
关键词
微动磨损
临界值
接触状态
摩擦
fretting wear
critical value
contact conditions
