Rolling-sliding dry wear testing — A vibration analysis

Accelerations have been measured on a modified Amsler machine during the dry rolling-sliding wear testing of rail steels. With certain combinations of contact stress and creepage two types of periodic circumferential surface deformation of the test discs have been observed; these are termed “corrugations” and “facets”. Discs were examined by surface profilometry. Corrugations were normally visually apparent, facets occasionally so. The conventional spring loading system of the Amsler machine was replaced by a rigid loading system. Wear rates, surface deformations and machine accelerations were not significantly affected. Corrugation wavelengths remained constant at two machine speeds, one double the other. Only at the higher speed was the frequency band of the corrugations, 2000–2600 Hz, close to the measured natural contact frequency of the elastically loaded discs. No vibrational source was found for the low faceting frequencies, typically between 55 and 70 Hz. These remained constant at both speeds. There appear to be high and low test condition boundaries for the formation of corrugations and a lower boundary for the formation of facets.