Advantages of using self-lubricating, hard, wear-resistant MoS2-based coatings

The paper reports a summary of MoS2 development through years. The properties of MoS2 coatings can be improved by the co-deposition of small amounts of titanium. These MoS2/Ti composite coatings known as MoST produced by closed-field unbalanced magnetron sputtering, are harder (1000-2000 compared to 400 HV for MoS2), much more wear-resistant (by a factor of 100) and also less sensitive to atmospheric water vapour (improvement by a factor of 2800 compared to MoS2) during tribological testing. They retain a low specific wear rate of 4 X 10(-17) m(3)/N m, a low friction coefficient of 0.02-0.1, and a high load-bearing capacity up to 5 GPa. Alternative MOS2/material composite coatings have been developed with similar properties. These coatings have given excellent industrial results for a wide range of cutting and forming applications. Recent industrial performance data related to the characteristics of these MoST auto-lubricating coatings, which are utilised today in large-scale production, are presented. (C) 2001 Elsevier Science B.V. All rights reserved.