不同载流条件下滑动电接触特性

Characteristics of the Sliding Electric Contact Under Different Currents

不同载流情况下,引起滑动接触面温升的主要因素有摩擦热、焦耳热、电弧热。接触面的温升使接触材料表面发生物理化学变化,从而改变了接触面成分,同时反过来影响接触面的滑动电接触性能。论文通过对铜基粉末冶金滑板、浸铜碳滑板两种滑板材料与铜锡导线的对磨实验,分析了两种滑板材料在受流摩擦时的磨损行为。研究表明:随着电流的增大,两种滑板材料的接触电阻、温度以及磨耗率都在增大,浸铜碳滑板材料的接触电阻变化率较小,但接触表面的温度偏高,该滑板磨耗率变化较小,受流磨损性能较好。

At different currents, temperature rising of sliding contact surface is caused by the combination of frictional heating, Joule heating and arc heating. At the same time, the sliding contact surface＇s temperature rising changes the contact materials＇ composition, and conversely affects the sliding contact characteristics. In this article, the Cu-based sintered alloy strip and Cu impregnation carbon strip are two experimental materials, and rub against the Cu-tin wire to analyze the wear characteristics with currents. By the comparative analysis, this article reaches conclusions that the contact resistance, the temperature and the wear rate of two slide plates rise with current. The contact resistance change rate of the Cu impregnation carbon strip are lower, but the contact temperature is higher; because of the existence of lubricant and arc-resistivity of carbon, the Cu impregnation carbon strip possesses lower wear rate and good wear characteristics with current.