Tribological performance of hybrid organo-silicate coatings

Abstract

Hybrid organo-silicate coatings (hybrid coatings) present many advantages and find use in many applications. However, their tribological performance has not been widely investigated due to the non-uniformity of the synthesized hybrid materials. In this work, nanoscratch tests have been employed for the investigation of wear mechanisms and organic–inorganic coatings adhesion. The tribological performance was investigated under low applied normal forces, in order to estimate the coefficient of friction (μ) values, the coatings resistance and the humidity effect when the synthesized coatings were submerged on a cell culture medium. Also, the performed plastic deformation was correlated with the experimental data and the surface images taken with a scanning probe microscope after the scratch tests. Furthermore, the experimental data were fitted and the relative coefficient of friction and cohesive force of each synthesized coating were calculated, since organic and hybrid materials do not conform with the classic tribology laws and are greatly affected by the adhesion forces observed between tip and sample's surface.