Modification of contact surfaces of steel based materials in dry sliding under electric current of high density

The purpose of the work was to study the interrelation of primary structure and wear resistance as well as to receive the initial ideas on contact features and surface layer deterioration in dry sliding against steel under electric current. The tribological behaviour of bearing steel and Hadfield steel (13% Mn) as well as the behaviour of composites on their bases was studied under electric current of high-density. Using X-ray phase analysis it was shown that the electrical current caused a modification of the surface layer of bearing steel and bearing steel sintered composite due to the formation of tribolayer and sliding surface melting in dry sliding against quenched AISI steel 1045. The formation of FeO in the tribolayer was observed also. This contributed to hardening of the sliding surface and to the realization of low wear intensity. Hadfield steel and a sintered composite based on it were capable of forming a tribolayer, where there was a low content of FeO on the sliding surface. This led to a high wear rate due to adhesion. The low thermal conductivity of Hadfield steel based materials should be considered as another reason for the rapid deterioration of their tribolayers.