In situ accelerated micro-wear — A new technique to fill the measurement gap

Abstract

A novel accelerated microtribological capability was implemented on a commercial ultra-low drift nanomechanical test system (NanoTest) by modification of the instrument's hardware. 10 and 25 μm spheroconical and Berkovich diamond probes were used in this study. To compare the accelerated micro-wear capability with existing nano-scratch tests, a range of thin film samples previously characterised were evaluated, including 80 nm ta-C film deposited on Si, 150 nm a-C:H thin film deposited on Si, metal-containing molybdenum disulphide (MoST) 70–150 nm, 70 nm a-C:H and 1 μm a-C films deposited on Si, multilayered 20 nm Si3N4/20 nm NiCr/80 nm Si3N4 multilayer coating deposited on float glass and additionally bulk Cu sample. Operational principles of the experimental setup are explained and reliability of the method is validated with a number of experiments. Results are presented and discussed following four experimental sections of this paper: (i) constant load micro-wear of various films on Si, (ii) constant load micro-wear kinetics of bulk Cu, (iii) ramped load micro-wear of thin films and (iv) tangential force calibration.