A RATIONAL APPROACH TO PRODUCTION OF MOLYBDENUM DISULFIDE FOR REDUCING FRICTION IN OPEN SYSTEMS

摘要

Molybdenum disulfide is one of the most widely used solid lubricants; the effectiveness of its action in this role results from its laminar structure and the fact that its yield strength in the direction perpendicular to the plane of the layers is of the order of 350 GPa (which is greater than the yield strength of a number of structural steels), together with the wide temperature range over which it can be used: from -45 to + 400 deg C [1].The MoS_2 used for lubrication in the RF is generally compliant with TU [Technical Specification] 48-19-133-85, containing no less than 99.671 percent of the primary compound and no more than 0.05 percent silicon. This level of purity is achieved either by multistage flotation/chemical purification of natural concentrates [2, 3] or by synthesis from the elements and/or their compounds [1, pp.215-221]. These groups of methods have a similar drawback: the need to use chemical- and heat-resistant equipment capable of withstanding the action of mineral acid solutions (HF, HNO_3, HCl) or vapor-phase sulfur and its combustion products.