Optimum Me-DLC coatings and hard coatings for tribological performance

In this study, hard coatings (TiN, TiCN, CrN, and CrCN) and Me-DLC coatings (Ti-x%-C:H and Cr-x%-C:H) were deposited on tungsten carbide (WC) substrate by multiarc physical vapor deposition (MAPVD) and unbalanced magnetron (UBM) sputtering, respectively. Counterbodies of the AISI 1045 steel cylinder and the AA7075T651 aluminum cylinder were used in the cylinder-on-disk, line-contact wear mode under dry condition; a counterbody of the AISI 52100 steel ball was used in the ball-on-disk, point-contact wear mode, under both dry and lubricated conditions. All wear tests were conducted with a reciprocating machine. After the tests, the most suitable coating for various counterbodies and test environments was selected, For the coating/1045 steel cylinder, the Ti-10%,-C:H coating possesses excellent tribological characteristics. For the coating/7075T651 aluminum cylinder, hard coatings display excellent wear resistance. Far the coating/steel ball, CrCN and CrN coatings display very little wear under both dry and lubricated conditions. On TIN and TiCN coatings, special wear mechanisms of material transfer, adhesion wear, and fatigue fracture occurred during initial tests under kerosene lubrication.