真空中GCr15钢球/CVD Cr_7C_3镀层钢盘摩擦副摩擦振动的研究

Study on Friction Vibration in Rubbing Pairs of Bearing Ball/Cr_7C_3 Coating in Vacuum

作者在对GCr15钢球/CVDCr_7C_3镀层钢盘摩擦副于大气中滑动干摩擦引起的摩擦振动进行考察分析的基础上,本文又对这种摩擦副在真空(6.67×10^(-3)Pa)中的摩擦振动特性进行了试验研究。试件系统为低刚度和小阻尼的弹性系统。试验信号由微机采集、处理并进行频谱分析。结果表明,真空中摩擦力振动的类型呈准谐波周期性自持振动,其与正压力及拖动速度无关,振动频率接近于系统在水平方向上的固有频率;摩擦副运动的平稳性与平均滑动摩擦系数接近反比例关系;真空中摩擦力的粘着分量是使摩擦振动加剧的主要原因;钢球的磨损体积与摩擦振动特性无关。

This paper reveals the testing results of friction vibration characteristics in rubbing pairs of bearing ball/CrrCs coating in vacuum (6.67 × 10-3Pa) , based on the earlier studies of the same friction vibration properties, with same kind of samples in air. The sample system belongs among the elastic system whose stiffness and damping is low. All the testing signals have been collected, processed and analysed by means of microcomputer. The results shown that the vibration type of frictional force is quasi-harmonic self-excited vibration in vacuum, it is not related to normal load and pulling velocity, and its vibration frequency in horizontal direction is approximate to the natural frequency of the sample system. The kinematical parameter of the rubbing pair is in the inverse proportional relationship to the average sliding friction coefficient. The results also indicated that it is the adhesive component of frictional force that let the friction vibration to be intensified. And the worn volume of bearing ball is not related to the vibration characteristics of frictional force.