Tribological evaluation of thermally activated CVD diamond-like carbon (DLC) coatings

• Published in: Surface & coatings technology Vol. 96; no. 2; pp. 230 - 235
• Main Authors: Hollman, P., Hedenqvist, P., Hogmark, S., Stenberg, G., Boman, M.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 25.11.1997; Elsevier
• Subjects: Applied sciences; Chemistry; Condensed matter: structure, mechanical and thermal properties; Diamond-like carbon coatings; Exact sciences and technology; Inorganic chemistry; Kemi; Mechanical and acoustical properties; Metals. Metallurgy; NATURAL SCIENCES; NATURVETENSKAP; Oorganisk kemi; Physical properties of thin films, nonelectronic; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Wear resistance; Wear resistance; Diamond-like carbon coatings; Synthetic diamond; Roughness; Mechanical properties; Friction factor; Experimental study; Coatings; Diamond structure; CVD; Surface hardness; Abrasive wear; SEM; Protective coatings; Tribology; diamond-like carbon coatings; FILMS; wear resistance
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/S0257-8972(97)00114-X

Diamond-like carbon coatings have been the subject of expanding technological interest for wear resistance and low friction applications during recent years. In this study, diamond-like carbon coatings were deposited by thermally activated chemical vapour deposition. The deposition temperature was 900°C and CH 2I 2 was used as a precursor. Tribological evaluation was performed by surface roughness measurement together with hardness, micro abrasion and friction. Furthermore, the residual stress of the coating was evaluated by a deflection method. The coating was analysed with nuclear reaction analysis, scanning electron microscopy and atomic force microscopy. The coating was very smooth ( R a = 1 nm) and free from pores. A high abrasive wear resistance slightly worse than physical-vapour-deposited TiN was measured. It exhibit a hardness of 2800 HV and a friction coefficient of about 0.2 in air (30–50% relative humididty). Furthermore, the coating has a compressive residual stress of 220 MPa. Hydrogen content and density of the coating were 9 at.% and 1.8 g cm −3, respectively.