Wear performance of DLC coating on plasma nitrided Astaloy Mo

Diamond-like carbon (DLC) coating was used to improve the hardness and tribological importance of the plasma nitrided Astaloy Mo. In this research, pre-alloyed Astaloy Mo and graphite powders were used as starting materials. The specimens were produced by single-sided pressing and sintered at 1120 degrees C for 30 min in the N-2/H(2 )atmosphere. Effect of DLC deposition on the hardness and wear behavior of nitrided Astaloy Mo as well as the effect of different conditions of the substrate was investigated. Plasma nitriding greatly improved the adhesion of DLC film on the substrate. Moreover, it was observed that the as-sintered substrates led to producing DLC films with more thickness and roughness and a higher adhesive strength. Wear results indicated that the wear performance greatly increased by DLC films applying. Adhesive and abrasive wear and pull-out of hard particles were identified as the main mechanisms of the DLC coatings deposited on the as-sintered substrate.