Microtribology today and tomorrow

Abstract

Very lightweight sliding parts are beginning to be used in magnetic recording and micromechanical systems which require wear rates that are almost zero. The wear of sliding surfaces subjected to light loads is primarily the result of surface interaction forces rather than of load or weight. New tools, such as scanning probe microscopes (SPMs) and computer simulation of molecular dynamics, have advanced our scientific understanding of micro-tribology. The SPM is also used to evaluate the microwear process and solid surface properties. The SPM and a surface force apparatus have also been used to investigate very thin liquid lubricant films on solid surfaces. Microtribology is expanding in many areas but it remains a somewhat haphazard field of knowledge. Almost all practical sliding surfaces have defects, damaged layers, and contaminants — i.e. they are neither well defined nor homogeneous. Untangling the complicated phenomena related to microtribology will require much more knowledge in both engineering and basic science.