Mechanism of Formation of Heterogeneous Dispersed Phase of Greases With Participation of Nanosized Additives and Its Influence on Properties of Lubricants

Abstract

It is shown that in the case of the formation of the heterogeneous structure of the dispersed phase (DP) of greases, which includes the soap component in the form of a complex salt of high molecular weight and low molecular weight acids and nanosized particles of the additive, a more branched structural framework of the DP is formed due to the presence of the additional crystallization centers in the form of the additive nanoparticles. This provides the improved colloidal stability, the greater load capacity and the higher dropping point of the lubricant. The additive nanoparticles implanted into the fibers of the soap component of the DP strengthen it and the probability of their aggregation is excluded. Using as an example the complex lithium grease modified by nanosized particles of the diamond-graphite charge ША-А (ShA-A), it is shown that the formation of the DP heterogeneous structure can improve the rheological and tribological characteristics of the grease in comparison with the lubricant of the same component composition, but having a single DP from the lithium complex and modifying nanoparticles ША-А (ShA-A) that are introduced into the dispersion medium (DM) (oil) separately.