This paper discusses the studies of the friction coefficient for natural and synthetic molybdenum disulphide MoS2 as well as for a new lubricating compound, tungsten disulphide WS2. Studies conducted by the author did not exhibit any differences in the friction coefficients of the above three compounds. The author concludes that on the basis of the tests conducted that the governing factor in the lubricating properties of solid compounds is their crystallographic structure this was verified by studies of the friction coefficient for molybdenum disulphide and tungsten disulphide. These tests also show that synthetically obtained MoS2 and WS2 compounds can be used as lubricating agents just as well as natural MoS2 molybdenite. Studies of the properties of WS2 and MoS2 also contribute to the solution of the problem of surface sulphiding of steel.
Edited trans. of Przeglad Mechaniczny (Poland) n9 p244-249 1960.