A Scanning Electron Microscopic Study of Wear Surfaces

Abstract

A critical SEM examination of the worn surfaces of pins of different ferrous and non-ferrous alloys was undertaken to obtain additional knowledge regarding the microscopic events that occur when the asperities of opposing sliding surfaces contact in the absence of any applied lubricant film. These observations were correlated with optical9 X-ray, wear, and frictional data. The materials examined were steel with pearlitic, spheroidized, normalized, and hardened structures; iron-tungsten single phase alloys; non-ferrous alloys, such as brass; and commercial aluminum and magnesium alloys. The nature of the surface and wear particle size and shape suggested possible wear mechanisms for “mild” and “severe” wear phenomena. Indication of frictional heating resulting in thermal softening was clearly noted. Luminescent mode of examination allowed identification of FeSe on the surface. It is suggested that a critically designed experiment coupled with stereoscopic SEM techniques be conducted for quantitative evaluation of wear process.