Microstructure and tribological behaviour of super-hard Ti–Si–C–N nanocomposite coatings deposited by plasma enhanced chemical vapour deposition

• Published in: Thin solid films Vol. 496; no. 2; pp. 438 - 444
• Main Authors: Ma, Dayan, Ma, Shengli, Dong, Hanshan, Xu, Kewei, Bell, Tom
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 21-02-2006; Elsevier Science
• Subjects: Carbon; Coatings; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Hardness; Materials science; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; Nanoscale materials and structures: fabrication and characterization; Organic-inorganic hybrid nanostructures; Physics; Tribology; Tribology and hardness; Coatings; Hardness; Carbon; Tribology; Inorganic compounds; Transition element compounds; Crystallization; Friction factor; XRD; Experimental study; Texture; Titanium nitrides; CVD; Transmission electron microscopy; Nanocomposites; Silicon nitrides; Carbon nitrides; Wear resistance; PECVD; Microstructure; Quaternary compounds; Nanostructured materials; X-ray photoelectron spectra
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2005.08.379

In this study, a series of new quaternary Ti–Si–C–N nanocomposite coatings have been deposited on HSS substrate at 550 °C using an industrial set-up of pulsed direct circuit plasma enhanced chemical vapour deposition (PECVD) equipment with a gas mixture of TiCl
4/SiCl
4/H
2/N
2/CH
4/Ar. The composition of the coatings can be controlled through the adjustment of CH
4 flow rate and the mixing ratio of the chlorides. Detailed structural and chemical characterisations using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) suggest the formation of a Ti (C, N)/a-C/a-Si
3N
4 nanocomposite structure. Ti (C, N) films show a (200) texture, which change to random orientation of the crystallites when the silicon content reaches about 9 at.%. The tribological behaviour of these coatings was investigated at room and elevated temperature. The results show that the nanocomposite Ti–Si–C–N coatings with low Si and high C contents have a lower friction coefficient of 0.17–0.35 at room temperature. The Ti–Si–C–N nanocomposite coating containing 12 at.% Si and 30 at.% C shows excellent tribological properties with a low friction coefficient of 0.30 and a low wear rate of 4.5
×
10
5 mm
3 N
−
1
m
−
1
at 550 °C.