Wear Behavior and Self Tribofilm Formation of Infiltration-Type TiC/FeCrWMoV Metal Ceramics Under Dry Sliding Conditions

Abstract

A new type high temperature self-lubrication TiC/FeCrWMoV metal ceramic was fabricated successfully by applying an innovating technology which molten solid lubricant (60Pb40Sn-15Ag-0.5RE) was infiltrated into metal ceramic preforms with an interpenetrating network using a vacuum high pressure infiltration furnace. The friction and wear behaviors of the composites were investigated using a pin-on-disk high temperature wear testing machine at different temperature (up to 800°C). The compositions, images and structures of worn surfaces were analyzed by means of scanning electron microscope (SEM), energy dispersive X-ray analysis (EDXA) and X-ray diffraction (XRD). The self-lubrication mechanisms of the composites were discussed. The experimental results indicated that during elevated temperature sliding, the solid lubricants were squeezed out of the micropores to the frictional surfaces to form PbMoO4, PbO, SnWO4, Ag2WO4 and Ag3Sn. The formation of lubrication film containing of these oxides and of intermetallic compounds was the main reason that the composites had good self-lubrication properties at high temperature. It was considered that the micro-pores on friction surface would be the crucial factors determining the self-lubricating properties of the self-lubrication composites.

Keywords

• metal ceramics
• self-lubrication mechanisms
• wear behavior
• infiltration
• high temperature