The present invention relates to a multifunctional lubricant composition which serves as a base oil for lubrication or as an additive for lubrication, including, with respect to 100 parts by mass of phosphorus compound (A) having a specific structure specified in the Description, 26 parts by mass to 43 parts by mass of phosphorus compound (B) having a specific structure specified in the Description, 0 parts by mass to 1.3 parts by mass of phosphorus compound (C) having a specific structure specified in the Description, and a total of 0 parts by mass to 1.3 parts by mass of triphenyl phosphate and tricresyl phosphate.

Provided is a solid lubricant that is non-black in color and capable of reducing industrial waste (environmental conservation), and further capable of achieving a balance among excellent lubricity, moisture absorption resistance, and corrosion resistance in a heavy working region, and a lubricating coating agent including the solid lubricant.

A solid lubricant including carrier particles including a lipophilic lubricating component that is at least one of an oil, an extreme-pressure agent, a soap, and a wax between particles of and/or between layers of at least one layered clay mineral selected from the group consisting of natural products and synthetic products of a smectite group, a vermiculite group, a mica group, a brittle mica group, a pyrophyllite group, and a kaolinite group.

A functional fluid composition containing a fluid base stock (e.g., a phosphate ester fluid base stock) as a major component, and an erosion inhibitor mixture as a minor component. The erosion inhibitor mixture contains at least a first erosion inhibitor (e.g., a perhalometallate or perhalometalloidate salt) and a second erosion inhibitor (e.g., an alkali metal salt of perfluoroalkyl sulfonic acid). Erosion inhibition of the functional fluid composition is improved as compared to erosion inhibition achieved using singly the first erosion inhibitor or the second erosion inhibitor, as measured by one or more of ASTM D2624, ASTM D974, ASTM D130 and ASTM D6304. A method for operating and lubricating a hydraulic system by utilizing as a hydraulic fluid, the functional fluid composition. A method for identifying erosion inhibition effectiveness of the functional fluid. The functional fluids are useful as aircraft hydraulic fluids.

The present disclosure relates to methods, systems, hydraulic fluids and additives for reducing the rate of surface current degradation for components in a hydraulic system, wherein the hydraulic system is exposed to phosphate-ester-based hydraulic fluid.

The present disclosure relates to methods, systems, hydraulic fluids and additives for reducing the rate of surface current degradation for components in a hydraulic system, wherein the hydraulic system is exposed to phosphate-ester-based hydraulic fluid.