APPLICATION OF LOW-TEMPERATURE PVD COATINGS IN ROLLING BEARINGS - TRIBOLOGICAL TESTS AND EXPERIENCES WITH SPINDLE BEARING SYSTEMS

The application of coatings for high speed hybrid rolling bearings wit h coated races and ceramic balls is being studied within the framework of European BRITE-EURAM Project BE 5963. In this paper the main innov ations of the ''Enhanced Sputter Ionic Plating'' PVD process developed by CEMECON to enable coatings at 160 degrees C is firstly described. Secondly, attention is focused on the results of tribological tests fo r the characterization of coatings in lubricated conditions performed by TEKNIKER. Finally, the outcome of spindle bearings tests of coated bearings carried out by WZL is presented. Titanium derivative coatings with a higher hardness than steel bring advantages in avoiding tribol ogical trouble under high stress conditions. CrN coatings show good be haviour under low load, high speed working conditions.