Tribo-characterization of silicon doped and nano-structured DLC coatings by metal forming simulators

Diamond-like carbon (DLC) coatings have been utilized as a protective tribo-coating of punches and dies to decrease friction in forming processes. Although their frictional performance is characterized by ball-on-disc or pin-on-disc methods, their practical endurance behavior must be evaluated by metal forming simulators with consideration of wear severities in each individual forming process. Both Si-doped and nano-laminated DLC coatings were employed to perform an engineering characterization of their durability and toughness in practical metal forming operations and to search for new directions for DLC coating technology development to prolong tool life.