Tribology parameters for friction materials

The tribology parameters of the friction materials are currently the coefficient of friction and the wear coefficient. They are determined depending on the material, the surface pressure and the frictional speed. These two parameters are not sufficient for an evaluation of the friction materials on the basis of a wear theory. Their validity is therefore limited. It is proposed to evaluate the friction materials on the basis of the energetic wear theory. The parameters are then the wear energy density, the shear stress of friction and the linear wear intensity. These values can be shown in a diagram and alloy; for the direct comparison of widely varying friction materials. The reference coefficient of friction is being introduced as a new wear parameter. The determination of the proposed parameters is made on a flywheel test rig, combined with the laser-optical online measurement of the wear particles. It was possible to demonstrate that the parameters correctly describe the practice-relevant requirements using two proven friction materials.