Micro-scale sliding contacts on Au and Au-MoS2 coatings

The microtribological properties of Au and Au-MoS2 coatings were examined using a nanoindentation instrument. MoS2 was chosen for this study as an additive to Au due to its positive influence on the mechanical and tribological properties. Reciprocating microscratch tests were performed using a diamond indenter with a tip radius of 50 μm and a range of normal loads between 0.2 mN and 5.0 mN. The friction and wear results, with respect to the two coatings, were correlated to different velocity accommodation modes and levels of adhesion. It was found that the addition of 20 mol% MoS2 to Au reduced the adhesion and limiting friction and also improved the wear resistance significantly. This coating shows potential for applications in microcomponents and microswitches due to its wear resistance, relatively low friction and good electrical conductivity.