Nanopowders of Different Chemical Composition Added to Industrial Lubricants and Their Impact on Wear Resistance of Steel Friction Pairs

Abstract

The authors have previously proposed and tested a method for increasing the wear resistance of heavy-loaded friction pairs by saturating industrial lubricants with the metallic nanopowder of the friction pair’s component that has a lower hardness. To confirm the effectiveness of this concept, this paper presents the results of experimental investigations into the tribological characteristics of two medium carbon steels (rail steel K74 and structural steel 20) during sliding friction. Friction surfaces lubricated with compositions based on the Bio Rail industrial lubricant were saturated with nanopowder additives of copper, carbon, and magnesium alloy, as well as K74 and 20 steels. The research findings indicate that lubricants saturated with nanomaterials of K74 and 20 steels help achieve the highest wear resistance, as compared to lubricants based on pure grease and lubricating compositions based on copper, magnesium alloy and carbon powders. The test results confirmed that the mean friction coefficient of the rail steel remained at the level of 0.25 for three hours of operation, which is optimal for the “wheel–rail” friction pair. The proposed method of manufacturing lubricating compositions can be used to improve the efficiency of lubrication of railway rails and rolling stock wheels.