Friction under elastic contacts

The friction coefficients and shear stresses for a sliding contact at low loads are calculated on the basis of the elastic contact and adhesion beneath a sliding spherical indenter and compared to experimental data. The contribution of the adhesion appeared to be negligible. The method allows either the critical shear stress to be assessed from experimentally determined friction coefficient and normal load or the friction coefficient to be calculated as a function of normal load for a material. As model materials, different hybrid organic-inorganic coatings as well as hot-pressed alumina and float glass are used.