Pesearch Paper / Surface Treatment : A Study on Synthesis and Aechanical Properties of WC-TiN Superhard Composite Films
윤주선Joo S . Yoon,한전건Jeon G . Han,명현식Hyun S . Myung
Abstract
Composite films have been one of approaches for new hard coating development and provided properties which are unachievable in uniform materials. Structurally, composite films tended to have dense and fine granular structure because column propagation was periodically interrupted by the nucleation of another phase. In this study, WC-TiN composite films were deposited on cemented carbide substrates by cathodic arc ion plating process. The chemical compositions and crystal structures were evaluated by energy dispersive spectroscopy(EDS) and X-ray diffractometry(XRD), respectively. Film thickness and fracture morphologies were investigated by using scanning electron microscopy(SEM). The mechanical properties such as film adhension and microhardness were evaluated by scratch test, microknoop hardness test and nano indentation hardness test. The microhardness of the WC-TiN composite film on cemented carbide was measured to be 4000(㎏/㎟) which is 1.5 times higher than that of the WC and TiN single layer. The critical load(Lc) of WC-Ti/WC-TiN multi-layer film was measured to be 48.5N in scratch test.