Graphene is a new type of carbon nanomaterials with excellent properties

and the graphene coating has great potentials for improving the performance of sliding electrical contact between rails and armature and the launching performance of electromagnetic railgun. We tested the performance of sliding friction and static contact resistance for the U-shaped aluminum armature coated with & without graphene comparatively. Besides

the U-shaped aluminum armature coated with & without graphene were launched comparatively on the same conditions to analyze the velocity of armatures and the interfacial characterization between rails and armature. The experimental results show that: 1) Graphene coating displays good lubricity

and the sliding friction coefficient between rails and armature reduces by about 25%. 2) Graphene coating increases the static contact resistance by 5%～10%

but it can still keep the good electrical conduction to some extent. 3) In a low-velocity launching condition

the velocity of the armatures coated with graphene increases by more than 23% compared with that of the armatures coated without graphene. 4) Graphene coating has the ability to depress the arc and to decrease the oxygen content in the sediment

accordingly

ensures good sliding contact state.