Solid lubricant coatings with co-sputtered metal and MoS 2 have shown favorable macrotribological properties at a wide range of contact stresses and humidity levels. These materials are also candidates for use in microcontacts and micro-electromechanical systems (MEMS), but their performance at this scale is poorly understood. For this study, microtribological properties of Au-MoS 2 and Ti-MoS 2 coatings, with varying metal additives of less than 15 at%, were examined using a nanoindentation instrument. Titanium and gold were chosen for this study as metal additives due to their different influence on the mechanical properties of the coating. The hardness and reduced modulus of the coatings increased with the addition of metal, when compared to pure MoS 2 . Reciprocating microscratch tests were performed with two spherical diamond tips (50 and 10 lm radii) in dry air. A range of normal loads were used between 0.2 and 5.0 mN. Friction and wear measurements were analyzed with respect to the variation in the contact pressure and compared to literature studies performed at the macroscale. Correlations were found between the coating mechanical properties, tip-coating adhesion, interfacial shear strength, and the formation of transfer films and tribofilms.

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