Tribological and corrosive behavior under HCl corrosive environment of diamond-like carbon films with doped H, Cr and WC

Abstract

Diamond-like carbon films exhibit low friction and strong wear resistance under various conditions. In order to evaluate tribological and corrosion resistant performance of different types of diamond-like carbon films in hydrochloric acid (HCl) environment, DLC, Cr/DLC, H/DLC and WC/DLC films were prepared by unbalanced magnetron sputtering technology. Their microstructure, mechanical properties, tribological properties and corrosion resistance were characterized and studied. The results show that the prepared DLC film exhibits the lowest wear rate in 1 M HCl solution. H/DLC film has an obvious corrosion resistance due to its high sp3 C bond and dense structure. Cr/DLC and WC/DLC films show a lower friction coefficient. In general, tribological failure of DLC film is mainly due to ordinary mechanical wear; while that of Cr/DLC film is mainly attributed to abrasive wear caused by, for example, hard particles and wear products; adhesive wear is found to be responsible for H/DLC film, which is caused by transformation of CH bond to oxygen group at the friction interface. The WC/DLC film is experienced with both local degradation and low resistance to elastic/plastic changes (H/E and H3/E2), and therefore both granular and chemical failures occurred. This study provides a complete and comprehensive understanding of tribological and anti-corrosive performance of diamond-like carbon films in hydrochloric acid environment, and can be used further as a reference for industrial applications.