The fretting abrasion of the bearing is caused by the reciprocating sliding of the small amplitude accompanied by the oxidation corrosion which occurs between the two contact bodies and often occurs between the raceway surface and the rolling body which are affected by the reciprocation or the vibration. Occurs between mating surfaces. When a car or machine is transported as a freight on a train, the impact at the rail joints often causes such damage to the bearings in the car or machine。 The reason for this is that, at rest, pulsating load and oxidative corrosion have been long-term, gradually forming such a form of wear even under a small load, in which the oxidation rate is also an important factor causing such damage. The vibration causes the characteristic energy states The metal molecules that escape from the surface quickly form oxides, which in turn exacerbate this wear.
Bearing fretting characteristics of the performance of the erosion: the formation of dark damage on the surface of the equidistant distribution of small pits, the interval is approximately equal to the spacing of the rolling body or its integral multiple, will appear as serious as the washboard-like concave and convex grinding pit, Or deeply embedded in the ferrule wall, often accompanied by brown red fine-grained rust, but the pit may sometimes be bright. This kind of pits is also called fake indentation。 Slight abrasion, especially when the oxidation is insignificant, is very difficult to distinguish from the plastic pits due to heavy load。 However, the fretting vibration will squeeze the lubricant to make contact Surface wear and wipe the surface of the original grinding marks, and true indentation is to retain the original traces, in most cases can still be distinguished.