THE TRIBOLOGICAL BEHAVIOUR OF CERAMIC MATERIAL

The actual material wear process is influenced by a set of specific factors, such as: their filling, the used speed and lubricant, the amount of material, hardness. Aim of study: is to determine the wear coefficient of the ceramic materials. Material and Method: we made disks with a radius of 2.5 cm and a 2 mm thickness, out of 2 types of ceramic restoration materials we found on the market: INLINE and HERA CERAM, on which we measured the friction coefficient and the amount of material used. The experiment was carried out using a CALOWER friction meter. The sliding speed is constant in time (about 150 r.p.m.) and acts on a variable sliding distance, between 3255 and 16277 mm, (corresponding to about 35000 mastication cycles, on a 0.5mm long occlusion). A force of 0.35N acts on the material samples. Results: the amount of material used increases with the filling increase for the whole sliding length, the number of rotations and friction length. The rate of transferred material decreases with the increase of the amount of certain constituents used, the material thus having better abrasion wear strength. Conclusions: the stress occurring on the contact surfaces is extremely interesting and enables us to understand their wear behavior.