合金工具鋼SKD11の摩擦摩耗特性および疲労強度に及ぼすプラズマ窒化およびDLC被覆から構成される複合処理の効果

抄録

In this study, we investigated the effect of the hybrid surface modification composed of plasma nitriding and DLC (diamond-like carbon) coating on the friction-wear properties and fatigue strength of alloy tool steel SKD11. Plasma nitriding and DLC coating improved the friction-wear properties, respectively. The hybrid surface modification was more effective to improve the friction-wear properties, because the planarity of the DLC layers was maintained by the formed hardened layer. The increase of hydrogen quantity in the DLC layers reduced the friction coefficient and improved the wear resistance. DLC coating suppressed fatigue crack initiation from the surfaces of the untreated and plasma-nitrided materials; however, its effect was not marked to improve the fatigue strength.