Study of Tribological Properties of Textured Boron-Doped Diamond Film under Water Lubrication

Abstract To explore the effects of different surface textures and boron doping on the surface friction properties of diamond film, cemented carbide tools were provided with elliptical and groove textures using laser technology. Undoped diamond (UDD), boron-doped un-textured diamond (BDUTD), boron-doped elliptical textured diamond (BDETD), and boron-doped grooved textured diamond (BDGTD) films were prepared by bias-enhanced hot filament chemical vapor deposition (BEHFCVD). The effects of different surface texture and lubrication conditions on the tribological properties of diamond coated tools were studied by TBT-M5000 ball-on-disk friction tester. The surface morphology, film quality, adhesion strength and residual material composition of diamond films were characterized by SEM, Raman, Rockwell hardness tester and EDS, respectively. The results show that boron-doped can effectively improve the film quality and the existence of texture further improves the adhesion strength of diamond film. Under water lubricated condition, the average friction coefficients of UDD and BDGTD film are 0.1426 and 0.123, respectively. The wear rate of the steel ball corresponding to BDGTD film shows excellent anti-friction performance, which is 1.37 × 10−8 mm3 / Nm. From the wear morphology, the UDD film pair has the largest wear diameter, which is 1.536 mm. The steel ball corresponding to BDGTD film has the smallest wear diameter, which is 1.258 mm. Compared with the other three films, the wear of UDD film is the most serious and BDGTD film shows the best wear morphology, this is due to the fact that texture can promote the lubricant to enter the friction contact surface, make the contact surface fully lubricated and can collect wear debris.