Effect of the temperature on the non-uniform wear mechanism of the carbon strip in a pantograph-catenary system with heavy electric current at high speed of 350 km/h

Abstract

As the current-carrying equipment for the high-speed railway, the pantograph-catenary system works under the condition of high speed and current density, which easy results in the non-uniform wear of the carbon strip in the pantograph-catenary system and affects the physical and chemical properties of the carbon strip. Especially, the heat-dissipation performance of carbon strips is deeply affected by non-uniform wear. The friction and non-uniform wear behavior of the carbon strip were studied under different working conditions (v = 350 km/h, F_n = 40–80N, I = 200–300A), using a ring-on-block friction and wear tester with a designed speed of 400 km/h. The temperature field, heat dissipation performance and their relationship with the wear characteristics of the carbon strip are also analyzed. The experimental results show that the temperature has a significant impact on the friction and wear behavior of the strip. The distribution law of the surface temperature of the carbon ribbon has a significant impact on its wear mechanism, that is: the areas with high surface temperature of the strip have severe wear, while the areas with low temperature show slight wear. In addition, the heat dissipation experiment results show that the heat flux density of thermal conduction in the slight wear area is nearly 40 times higher than that in the severe wear area. There is a clear coupling relationship between heat dissipation and wear of the carbon strip. Reducing delamination wear is one of the important ways to decrease the non-uniform wear of the carbon strip.