COMPARATIVE TRIBOLOGICAL BEHAVIOURS OF HARD AND SELF- LUBRICATING COATINGS DEPOSITED ON HEAT TREATED STEELS

The purpose of this study is to investigate comparative tribological behaviours of PVD hard coatings (TiN, TiAlN, TiCN and ZrN) and self-lubricating coatings (MoS2, PTFE and WS2) deposited on heat treated steels. The sliding tests with bondary or dry sleading were caried out using block on disc testing rig, warying the levels of contact loading and sliding speed. Obtained results for the friction coefficient and resistance to wear provide the possi-bility of comparative analysis of tribological effects of the tested coatings. Though the testing of coating does not give the same characteristics in the variable condi-tions of contact (normal loading and sliding velocity), it can be concluded that the applied surface treatments can significantly contribute to tribological improvement of tested steels