FRICTION CHARACTERISTICS AND THE WEAR PROCESS OF METAL PAIRS IN SLIDING CONTACTS - WITH APPLICATIONS TO MODELING WEAR OF POWER-PLANT COMPONENTS

The wear and friction characteristics of several material combinations subjected to wide range of test conditions are examined. In the first series of tests, a fundamental investigation of wear particle formati on has been conducted for hardened steel-on-martensitic grade stainles s steel contact subjected to a uni-directional sliding motion with 2 m m stroke length. Results of detailed studies of the wear scar formatio n from the beginning few sliding strokes to after tens of thousands of repented cycles are presented, They reveal that extensive geometry tr ansformation occurs in the first few cycles of contact. In the second series of tests, the friction characteristics and wear processes of se veral material combinations used in nuclear power steam generators und er similarly low-amplitude but with reciprocating sliding contacts are studied, The combined results from these two separate studies indicat e that the friction characteristics can provide an insight into the mi ld and severe wear processes, The friction characteristic is an import ant parameter in predictive wear models that correlate the mass losses with the frictional work at the interface. (C) 1997 Elsevier Science S.A.