The Friction and Wear Properties of Some Proprietary Molybdenum Disulphide Spray Lubricants in Sliding Contact with Steel

摘要

Sliding tests performed on a pin-on-disk rig in a clean room and in vacuum showed that Molykote 106 and Everlube 811 perform well in air and vacuum, so lubrication and wear mechanisms were studied in further tests on Molykote. The test was interrupted at regular intervals and pin and coated disk wear was estimated quantitively. Results indicate three distinct stages in lubrication: (1) the lubricant coating supports the applied load entirely, a film of material being sheared between the bulk of the coating and the steel pin; (2) The metallic contact and wear occur between the pin and the disk asperity peaks, lubrication being provided by a thin film (0.2 to 0.5 microns thick) of lubricant between the pin and the worn asperity contact zones; and (3) failure occurs after the lubricant supply from the valleys between the asperity peaks becomes insufficient to prevent steel-on-steel contact and adhesive wear.