Tribology of unlubricated sliding contact of ceramic materials and amorphous carbon

This work deals with unlubricated sliding contact of SiC and Al2O3 spherical sliders against carbon-coated thin-film magnetic rigid disk in a wide range of sliding velocity of 0.5-16.6 m s(-1). Grain detachment from the ceramic slider surface was the most important mechanism controlling the life of the thin carbon coating, especially at low sliding velocity. Silicon carbide provided much longer life of the carbon coating compared with alumina, although the difference decreased with the increasing sliding velocity. At high velocity, a high friction-generated flash temperature was mostly responsible for the coating failure. A film formation of agglomerated ceramic wear particles was observed for both SiC and Al2O3. A model which summarizes behavior of wear particles at the contact interface was suggested.