Deposition of TiN, TiC, and DLC Coatings by PACVD

Introduction

In recent years, the growing demand of industries has been increased to improve surface properties of industrial parts (Azadi, 2014). Thus, the usage of various coatings has been spread during last years. Nitrides and carbides of the group IV, V and VI transition metals are important materials which are used for depositing thin coatings in industrial applications (Rie, 1993). While nitride coatings have comparatively good thermal stability and lower interaction tendency with other materials, carbide coatings possess high hardness and better adhesion to metallic substrates (Pfohl, 1992).

Titanium carbide (TiC) and Titanium nitride (TiN) are two materials that belong to the hard material group. TiC and TiN coatings are utilized in various industrial applications such as automobile and aerospace parts, cutting and forming tools, grinding wheels, molding and forging applications due to good mechanical properties including high hardness, low friction coefficient, excellent wear resistance and corrosion resistance in different harsh environments and high resistance to tribo-oxidation and surface fatigue (Shanaghi, 2012, Badisch, 2003). TiC layers are also used as heat shield coatings for atmospheric reentry of spacecraft and biomedical instruments. Graphite substrates which are coated with TiC and TiN layers are promising for using as the container material for pyro- chemical processing of certain rare-earth and nuclear metals, where chemical inertness and a good match of thermal expansion coefficients are required (Maiya, 1998). The deposition of TiC layers on titanium substrates would be useful as the abrasion resistant material for abutment parts of dental implant and sliding parts of artificial joints (Zhu, 2012). Consequently, such coatings are widely used in various industrial applications ranging from machining tools to decorative items (Stoiber, 2003). Similar to TiC layers, Diamond like Carbon (DLC) films were also used for the same applications.