In order to study the contact wire wear of metro rigid catenary system,taking the metal impregnated carbon sliding plate/copper silver alloy contact wire commonly used in metro rigid catenary system as the friction pair,through simulating the operation parameters of metro pantograph catenary system,the wear mass loss,friction coefficient and variation of current carrying efficiency with sliding distance of a metal-impregnated carbon strip rubbing against a copper-silver alloy contact wire with and without spark discharge were studied by means of a current-carrying friction and wear tester.The test results show that the wear mass loss of the contact wire and the metal-impregnated carbon strip increases significantly with spark discharge.When spark discharge occurs,the friction coefficient is small,and the current-carrying efficiency of the pantograph-catenary system decreases significantly and has a large fluctuation.The surface morphology of the metal-impregnated carbon strip and the contact wire after testing shows that spark discharge will increase the number and size of ablation pits on the worn surface of the metal-impregnated carbon strip.At the same time,there will be large-area material spalling of sliding plate and more surface cracks,and the surface morphology of contact wire becomes more rough.