Tribological and mechanical properties of the multi-layer DLC film on the soft copper substrate

Abstract A kind of the Cu-based multi-layer DLC film was designed, and then prepared by pulsed laser deposition. Firstly, the Ti and SiC layers were deposited in succession to increase the adhesion strength of the upper layers on the Cu substrate. Secondly, the periodic DLC/SiC layer was deposited. The periodic DLC/SiC layer not only avoided the accumulation of the inner-stress in the thick DLC layer, but also reduced the hardness difference between the soft Cu substrate and the hard DLC layer. Finally, the outer functional DLC layer was prepared to improve the anti-wear property of the sample. The nano-scratch test showed that the critical load of the multi-layer DLC film on the Cu substrate approached to that of the pure DLC film on the Si substrate. The micro-tribometer test showed that this multi-layer DLC film provided a low-friction and wearable surface for the Cu sample.