The unlubricated fretting wear of mild steel in air

Abstract Fretting experiments were carried out on mild steel in air to long sliding distances over a range of loads and stroke amplitudes. For peak-to-peak fretting amplitudes greater than 5 μm, three fretting stages were identified: an initial adhesive transfer stage, an intermediate stage where both metallic and oxide debris were produced and a terminal stage characterized by extensive oxide debris beds and continuing wear rates some 50 times smaller than in the previous stage. The nature of the contact and the ability of the oxide beds to bear load are discussed. Some dependence of wear rate on amplitude was found, but this was smaller than that found by other workers from short-term tests.