Understanding of Scuffing Process by Several In-Situ Observation Techniques

Abstract

The lubricated area can be recognized as “an enclosed space”surrounded by solid surfaces with relative motion. The solid surfaces are separated by thin films such as the hydrodynamic viscous film, absorbed film, and chemical reaction film. The orders of the thicknesses of the films range from nm to μm. In the lubricated area complex and transient phenomena occur based on the physical, chemical and material behaviours. Therefore, it is necessary but significant difficult to extract in situ information from the enclosed space without disturbances. One of ways to access to the lubricated area for in situ extraction of information is to replace one or both of solid surfaces with transparent material to employ optical techniques. So far, many in situ optical observation, measurement, and analysis techniques have been developed for the lubricated area. The author has also developed several in situ optical techniques for a better understanding of “scuffing”, which is a catastrophic failure with a big wear scar as a result of significant increases in friction, wear, temperature, and vibrations. In this paper, developed in situ optical techniques, the scuffing process, and specific phenomena in the scuffing process are introduced.