Chemical vapor deposition of diamond coatings on tungsten carbide (WC–Co) riveting inserts

We report a new industrial application of diamond coatings, by depositing diamond thin films on tungsten carbide (WC–Co) riveting inserts to achieve improved wear resistance and tribological behavior. The riveting inserts are widely used by chain manufacturing industries to guide the pin through its groove. Diamond coatings were deposited on the WC–Co riveting inserts by using hot filament chemical vapor deposition technique. Deposited films were characterized by using X-ray diffraction, a scanning electron microscope (SEM), Raman spectroscopy and a nanoindenter. The SEM micrograph of the deposited films revealed different surface morphologies and crystallite sizes in the groove and in the flat region of the riveting insert. The results concerning the different morphologies and crystallite sizes on the substrate surface are discussed. The coated riveting inserts showed an enhanced performance in the preliminary applied test.

► Diamond coatings were deposited on WC–Co riveting insert by using hot filament CVD. ► Geometrical variation on the substrate surface leads to different crystallite sizes. ► MCD on the flat surface and NCD on the grooved surface were obtained. ► Hardness of the coating depends on the crystallite size and surface morphology.