Micro-wear technique and its application to ultra thin film systems

Abstract

A mirco-wear testing technique has been developed by incorporating a piezoelectric pusher into an existing micro-indenter system. The pusher and its associated servo-control circuitry were designed to generate a precise reciprocating horizontal motion at the indenter tip for implementing micro-scale wear test. The information acquired from the test includes the wear loading curve, i.e., the normal applied load versus wear penetration depth, the friction force and in turn, the apparent wear friction coefficient. Acquiring the electrical resistance across the coating thickness is also a possible if an electrical conducting indenter is utilized. Furthermore, in collaboration with the surface characterization tools, the wear morphology revealed useful information regarding the coating failure mechanism(s) and shed some light towards understanding coating tribology. The tester design concepts, operating procedure, data acquisition and analysis will be examined. Experimental results on ultra thin carbon coatings with various thicknesses will be employed to illustrate the capabilities of the microwear tester.