Dry slipping steel–steel contact at high current density

Resumo

The behavior of steel 3 in dry slipping under the action of high-density electric current is studied. In these conditions, the surface layer undergoes plastic deformation; its temperature rises; and new phases and structural defects are formed. That gives rise to a layer of secondary structures. The basic factor disintegrating the surface layer is the contact current density. The mean contact temperature and layer thickness of the secondary structures increase with increase in current density. The variation in wear rate and electrical conductivity with change in contact temperature is studied. The wear rate depends linearly on the contact temperature in normal wear. Catastrophic wear appears as sharp increase in the wear rate and simultaneous decrease in the contact electrical conductivity at 500—600°C. The thickness of the layer of secondary structures is 50 μm in these frictional conditions.