Wear resistance of a sliding electric contact containing recycled ShKh15 steel

The volt-ampere characteristic and linear wear rate of a model composite containing recycled ShKh15 steel are determined at sliding velocities of 2, 5, and 10 m/s. It is shown that secondary structures appear in the friction zone at current density >100 A/cm2; these structures possess both good electric conductivity and poor plasticity. It is established that debris appear due to the brittle fracture of the secondary structures. Introduction of Pb-Sn alloy into the friction zone is shown to relax mechanical stresses, to eliminate wear during sliding at the current density 250 A/cm2, and to reduce the contact electric resistance.