Tribological characteristics of Si3N4-based composites in unlubricated sliding against steel ball

The dry-sliding wear mechanism of Si3N4-based composites against AISI-52100 steel ball was studied using a ball-on-disc mode in a reciprocation motion. The addition of TiN particles can increase the fracture toughness of Si3N4-based composites. The fracture toughness of Si3N4-based composites played an important role for wear behavior. The Si3N4-based composites exhibits a small friction and wear coefficient compared to monolithic Si3N4. Atomic force microscopy (AFM) studies displayed fine wear grooves along the sliding traces. The subsurface deformation shows that the microcrack propagation extends along the TiN/Si3N4 grain interface. The wear mechanisms were determined with scanning electron microscopy, transmission electron microscopy, X-ray diffraction and atomic force microscopy.