The Improvement of Tribological and Fatigue Properties of Aluminum Alloy coated DLC Hybrid Surface Modification

Abstract

Aluminum alloy has been used in several kinds of industries against a background of environmental problem and energy saving because aluminum alloy has a lot of advantages ; lightness, recyclability and good corrosion resistance. However, aluminum alloy has poor wear-resistance, so in order to solve this problem, DLC (Diamond Like Carbon) coating which indicates high tribological properties was performed. However, there are some reports which are concerned that coated materials like DLC indicate low fatigue strength compared with substrate only due to high heating history during the coating process. So, in this study, in order to improve wear resistance and to prevent the base material from decrease of fatigue strength, original DLC coating was suggested ; (i) coating process was performed by using UBMS (Unbalanced Magnetron Sputtering) method, and (ii) inter-layer which was doped Tungsten was formed on the substrate, and on the inter-layer (iii) two kind of DLC coatings were laminated for nano order. Wear tests and fatigue tests were carried out. Aluminum alloy coated DLC indicated very low wear rates, excellent tribological properties. Furthermore, it indicated high fatigue strength compared with substrate only.