基于相对稳定系数的滑动电接触特性

Sliding Electrical Contact Characteristics Based on Relative Stability Coefficients

利用自行研制的高性能滑动电接触实验机,对铜基粉末冶金滑板的滑动电接触特性进行实验研究。通过引入两个相对稳定系数和载流效率值对实验结果进行分析,得出滑板的滑动电接触特性与接触压力、滑动速度和接触电流之间的关系。在滑动速度恒定的条件下,增大接触压力,摩擦系数会增大,却改善了滑板的受流质量和摩擦副的摩擦稳定性,从而使磨耗率呈现先减小后增大的U字形变化规律,磨耗率最小时对应的接触压力阈值随接触电流的增大而增大。在接触压力恒定条件下,摩擦副的摩擦系数随滑动速度的增加不断减小,但其摩擦稳定性及受流质量却不断恶化,磨耗率随滑动速度的增加而减小,随接触电流的增加而增大。

In order to research the sliding electrical contact characteristics of Cu-base powder metallurgy strip under sliding electrical contact conditions, a lot of experiments were carried out with a self-developed high-performance sliding electrical contact testing instrument. The experimental results were analyzed by introducing two relative stable coefficients and current-carrying efficiency, some rules between the above characteristics of slide and contact pressure, sliding speed and contact current were obtained. Under constant sliding speed conditions, the friction coefficient increases with the increase of contact pressure, but both the property of current-carrying and the friction stability are improved. So, the curve of wear rate and contact pressure is a U-shaped curve. It＇s shown that the wear rate firstly decreases and then increases. The threshold of contact corresponds to minimum wear rate will increase with the increase of contact pressure. Under constant pressure conditions, the friction coefficient will decrease with the increase of sliding speed, while both the property of current-carrying and the friction stability are deteriorated. The wear rate will decrease with sliding speed and increase with contact current.