Experimental research on the friction and wear properties of a contact strip of a pantograph–catenary system at the sliding speed of 350 km/h with electric current

The friction and wear properties of a contact strip in a contact strip rubbing against a contact wire were studied. A series of experimental tests on the vibration between the contact strip and contact wire were conducted on a high-speed block-on-ring tester under the conditions of electric current of 0 A and 250 A, sliding speed of 200-350 km/h and normal loads of 120 N. Scanning electron microscopy (SEM) was used to observe morphology of the worn surfaces. Experimental results indicate that the vibration of the contact strip is aggravated with increasing sliding speed. In contrast with those without electric current, the friction coefficient of the strip against the contact wire decreases and the wear rate increases obviously with increasing sliding speed. With the increase of the sliding speed, the contact surface temperature between the strip and contact wire with electric current grows faster. The arc discharge becomes stronger and stronger with the sliding speed, which results in aggravated arc erosion wear on the surface of the strip. Delamination wear and arc erosion wear are two main wear mechanisms for the strip against contact wire with electric current of 250 A when the sliding speed is bigger than 250 km/h.