Investigating alternatives to Molybdenum disulfide by means of RVT- and DFBT-Tribometer

摘要

The recent years showed a dramatic increase of raw material costs, among others for Molybdenum disulfide. In various publications alternative solid lubricants were presented by comparing properties on the well known Four-Ball-Tester and the Timken machine. The results from these machines were not always satisfactory for finding the right solution in terms of solid lubricants. Very often the alternatives were combination of Molybdenum disulfide with other solid lubricants, most likely graphite. By means of the RVT- and DFBT-Tribometers it was possible to distinguish more between the properties shown by Molybdenum disulfide and its alternatives like e.g. Bismuth sulfide, Tinn disulfide, Graphite etc. in lubricating greases and pastes. Various test parameters, such as low and high speeds and/or loads enabled to show the different effects caused by the solid lubricant used. By doing so it was possible to find alternatives to Molybdenum disulfide depending on the application like lubricating grease or paste. The results from the tribometers were also compared to the findings on the Four-Ball-Tester and the Press-Fit-Test.