Heshmat, H. “The Rheology and Hydrodynamics of Dry Powder Lubrication,” (1991) Tribology Transactions, Volume 34 (3), pp. 433-439.
This paper conceptualizes a powder lubrication mechanism which closely resembles that of a hydrodynamic fluid film. Based on the observations of past investigations and on the author’s experiments, it is postulated that a layered shearing of the compacted powder generates velocity, density, and temperatures profiles akin to fluid film bearings. Thus a lubricant consisting of a fine powder inserted either deliberately or one generated by the wear of the mating surfaces, constitutes a viable lubricant that generates the required flows and pressures to prevent contact between the surfaces.