Abstract:In order to better simulate the actual application conditions of metal-impregnated carbon strip,the test sliding distance was set at 1 000 km,the block-on-ring high-speed friction and wear tester was used to simulate the operating conditions of the subway train in the rigid catenary system to study the current-carrying friction and wear performance of metal-impregnated carbon strips against a rigid catenary under different normal force.The results show that as the normal force increases,the average friction coefficient and current-carrying efficiency increase,the arc energy decreases,and the temperature and wear rate of the metal-impregnated carbon strip show a downward trend.With the increase of the sliding distance,the wear rate of the strips decreases first and then trends to be stable.The results of SEM observation on the strip scars show that when the normal force is low,there are more ablation pits and cracks on the strip surfaces,and the wear mechanism of the strips is dominated by arc ablation and layered spalling.when the normal force is high,scratches and wear debris appear on the surface of the strips,and the abrasive wear is more obvious.It can be concluded that properly increasing the normal force can effectively restrain the arc ablation,reduce the surface cracks and ablation pits of the strip,and thus reduce the wear of the strip.