Coating characteristics and tribological properties of sputter-deposited MoS2/metal composite coatings deposited by closed field unbalanced magnetronsputter ion plating

As previously reported (V.C. Fox, N.M. Renevier, D.G., Teer, J. Hampshire, V. Rigato, Proceedings of the PSE Conference in Garmisch Partenkirchen, 14- 18 September 1998, Germany, Surf. Coating Technol., in press) the propertie s of MoS2 coatings deposited by dosed field unbalanced magnetron sputter io n plating (CFUBMSIP) can be improved by the co-deposition of a small amount of titanium. These MoS2/Ti composite non-multilayer coatings known as MoST TM, are harder (10-15 GPa) and more adherent (critical load scratch above 1 20 N), much more wear resistant (10(-16)-10(-17) m(3)/mN), and higher load bearing (3.5 GPa) than pure MoS2 coatings. They have similar low friction t o pure MoS2 coating (mu of 0.02 at 40% humidity) but are much less sensitiv e to atmospheric water vapour Juring tribological testing at high humidity. MoS2/Ti composite coatings have given excellent industrial results for a w ide range of cutting and forming applications. Other metal additions such a s Cr, W, Mo and Zr have been studied with varying compositions and substrat es. Laboratory test results using micro hardness and nanoindentation testin g, scratch adhesion testing, pin on disc and reciprocating friction and wea r tests are presented. Structural analysis was carried out using X-ray diff raction, optical microscopy, scanning electron microscopy and transmission electron microscopy of cross-sections through the coating. This paper prese nts further analysis on the MoS2/Ti composite coatings and with other metal additions such as chromium, tungsten or zirconium. (C) 2000 EIsevier Scien ce S.A. All rights reserved.