受电弓滑板载流磨损机理演变过程试验研究

为了研究高速弓网系统材料载流摩擦磨损行为,采用高速环-块式载流磨损试验机,研究了载流200 A、法向载荷70 N、滑动速度80~160 km/h条件下,纯碳滑板/铜合金接触线之间电弧放电现象和纯碳滑板的载流磨损特性,并用光学显微镜来观察滑板磨损表面形貌.研究结果表明:随着试验时间的增加,滑板振动和电弧放电现象逐渐加剧,电弧放电频率先增加后逐渐趋于稳定,电弧平均单次放电能量也增加,滑板磨损量缓慢增加后快速上升;当滑动速度为160 km/h时,试验时间50 min的磨损率(0.037 27 g/km)是试验时间10 min磨损率(0.013 40 g/km)的3倍;高速载流条件下,滑板磨损机理随着试验的进行发生了由轻微机械磨损到重机械磨损伴随轻微电弧侵蚀,最后转变为机械磨损和电弧侵蚀共存状态的变化. 

Experimental Study on Evolution of Wear Mechanism of Contact Strip with Electric Current

In order to investigate the friction and wear behavior of the high-speed pantagraph-caternary system, a high speed ring-block wear tester was used to study the wear characteristics of carbon contact strip and the arc discharge phenomenon between the copper alloy contact wire and the carbon contact strip with electric current. The tests were conducted under the condition of electric current 200 A, normal load 70 N, and sliding speed 80-160 km/h. A optical microscope was used to observe the topography of the strip's wear surface. The results indicated that vibration and arc discharge occurred to the contact strip and intensified with sliding time; the arc discharge frequency increased first and then kept stable gradually. With the experimental time increasing, the average single arc discharge energy increased; the wear loss increased slowly first and then increased sharply. When the sliding speed was 160 km/h, the value of wear rate at the test time of 50 min (0.037 27 g/km) is 3 times that of 10 min (0.013 40 g/km). Under the high-speed operation conditions with electric current, the wear mechanism of the strip changed from a slight mechanical wear to a serious mechanical wear accompanied with slight arc erosion, and finally to a mechanical and arc erosion mixed wear.