Nanocomposites hold great promise for space and ambient applications on account of their ability to adapt to and exhibit low friction and wear rates in constantly varying environmental conditions. In order to explore the impact of nanocrystalline grain size and fractal scaling properties on tribological performance, the authors have performed experimental and theoretical studies examining nanotribological properties of gold-ytrium based nanocomposites. These include modelling the impact of grain size on film stress and wear attributes and the documentation of surface region grain size distributions. The authors' modelling results associate smaller grain sizes with lower wear, consistent with experimental observations for the range of grain sizes studied. The findings show promise for nanoscale customisation of coatings so as to tailor them at the nanoscale in an application specific manner.