Pin-on-Disc Tests of Pelletized Molybdenum Disulfide

Kaur, R.G., Heshmat, H. and Higgs, C.F., III “Pin-on-Disc Tests of Pelletized Molybdenum Disulfide,” (2001) Tribology Transactions, Volume 44 (1), pp. 79-87.

The development of powder lubricated back-up bearings for magnetically levitated rotors operating under high speed, high temperature and even vacuum conditions is being investigated for Gas turbine engines and Flywheel Energy Storage Systems.  The objective of this work was to evaluate the performance of Molybdenum Disulfide as a solid lubricant via a series of tests using a modified pin-on-disk tribometer to examine the behavior of compacted pellets of Molybdenum Disulfide run against Titanium Carbide disc with respect to developing a powder pellet, which would provide adequate lubrication at the contact interface and also a low coefficient of friction.  This paper reviews some recent advances in perfecting the solid lubricating film, in terms of wear and friction characteristics, particle size, level of powder compaction, bulk density, effects of external loading and transfer characteristics of the powder  pellets.  Some of the conclusions reached were that high compaction pressures which provided more stable pellet structure and high external loadings are often conductive to proper performance of powder layers.