Abstract
In order to achieve highly functional materials which show high fatigue and high tribological properties, two surface modifications, high carbon carburizing and DLC (Diamond Like Carbon) coating, were applied to low carbon steel (SCM415). However, there are some reports which raise the concern that coat materials like DLC show low fatigue strength compared with substrate only due to high heating history during the coating process. So, in this study, in order to prevent the base material from losing fatigue strength, DLC was coated by using the UBMS (Unbalanced Magnetron Sputtering) method, which can coat at low temperature. Furthermore, three types of DLC-coated specimens with different coating structures were prepared. Rotational bending fatigue tests and friction-wear tests were carried out. It was clear that the friction coefficient of each specimens coated with DLC stabilized under 0.1. And, the specimen coated a 5 μm-thick DLC film shows the highest tribological properties because the DLC coating was transcribed on the opposite material during the wear process. Furthermore, no decreases in fatigue strength were observed for any of the coated specimens. It can be concluded that it is possible to achieve highly functional materials by applying DLC hybrid surface modification as suggested in this search.
