A method of using energy-efficient lubricant compositions to reduce wear between two surfaces exposed to a high shear condition is provided. The lubricant compositions comprise polysiloxane base oils having alkyl, aryl, or a combination of alkyl and aryl functionality. The polysiloxane base oils may be defined according to the formula: ##STR00001##
wherein R, and R′ are independently selected, such that R is an alkyl group having between 1-3 carbon atoms; R′ is an alkyl or aryl group having between 6 to 20 carbon atoms; and m and n are integers, such that 25<(m+n)<500 and the ratio of m/(m+n) is greater than 0.05 and less than 1.00.

A rolling bearing that can prevent peeling on a surface of an iron-based metal member by hydrogen brittleness even under a severe environment is provided. The rolling bearing 1 has plural bearing elements formed of an iron-based metal, and a lubricant composition 7 that lubricates metal contact surfaces of the respective bearing elements, the lubricant composition 7 is a grease containing a base oil and alkanolamine and being free of alkali metal salts and alkaline earth metal salts of inorganic acids, the base oil is at least one oil selected from alkyl diphenyl ether oils, poly-α-olefin oils and ester oils, and the alkanolamine is contained by 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the base oil and a thickener.

A sliding member includes: a lining layer formed from an alloy having a predetermined shape; and an overlay layer formed on an inner circumferential surface of the lining layer, the overlay layer being formed of a resin, the overlay layer sliding with a shaft, the overlay layer including a raised portion a height of which in a predetermined area including each of an edge in an axial direction of the shaft is greater than a height of another area of the overlay layer.

A urea grease of the invention is prepared by applying shear at a shear rate of 10.sup.2 s.sup.−1 or more to a mixture solution of an amine mixture containing an alicyclic monoamine and a chain aliphatic monoamine, and a diisocyanate compound to cause a reaction in the mixture, in which the urea grease has Peak High32-64s of 1.5 or less and Level High32-64s of 10 or less according to an FAG method.

An aluminum alloy for a slide bearing of the present invention contains: 0 mass % or more and 10.0 mass % or less of Sn and 0 mass % or more and 5.0 mass % or less of Si, 0 mass % or more and 2.0 mass % or less of Cu as a solid-solution strengthening component, at least one of 0.05 mass % or more and 0.35 mass % or less of Cr, 0.05 mass % or more and 1.5 mass % or less of Mn, and 0.05 mass % or more and 0.3 mass % or less of Zr as a precipitation strengthening component, 2.3 mass % or more and 6.0 mass % or less of Ag, a part of which is dissolved to form a solid solution and the rest of which is precipitated, and the balance consisting of unavoidable impurities and Al.

A lubricant composition comprises an anti-wear and or/friction modifying additive which is an ester of a fatty acid and a polyol. At least 50% by weight of the additive is in the form of a mono-ester, and is preferably a mono-glyceride. The lubricant composition may be used in an internal combustion engine.

A bearing material may include a polyamide-imide polymer material and a difunctional crosslinking agent comprising a hydrocarbon chain and two functional groups. The functional groups may be selected from the list: amino, acid, epoxide, thiol, isocyanate.

Provided is a lubricating oil composition for air compressors containing a polyalkylene glycol-containing base oil (A) and a rust-preventive agent (B), wherein the content of the polyalkylene glycol is 65.0% by mass or more based on the total amount of the composition. The lubricating oil composition is excellent in oxidation stability and also in rust prevention and storage stability. Also provided are an air compressor lubricating method and an air compressor using the lubricating oil composition.

The invention provides a grease composition, being a grease composition containing a base oil and, as a thickener a calcium complex soap, and being a grease composition using for the carboxylic acids forming the aforementioned calcium complex soap substituted or unsubstituted C18-22 straight-chain higher fatty acids, aromatic monocarboxylic aromatic acids having substituted or unsubstituted benzene rings and C2-4 straight-chain saturated lower fatty acids, wherein the aforementioned substituted or unsubstituted C18-22 straight-chain higher fatty acids include behenic acid and the amount of behenic acid used, as a mass ratio in terms of the total amount of the aforementioned substituted or unsubstituted C18-22 straight-chain higher fatty acids used, is from 25 mass % up to 70 mass %.

Provided is a grease composition including a base oil (A) containing an alkyl naphthalene (A1) and an aliphatic diurea (B) represented by general formula (b1):
R.sup.1—NHCONH—R.sup.3—NHCONH—R.sup.2  (b1) (wherein, R.sup.1 and R.sup.2 each independently represent a monovalent aliphatic hydrocarbon group having 9 to 20 carbon atoms, and R.sup.3 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms), wherein a content of the aliphatic diurea (B) is 20 to 30% by mass based on a total amount of the grease composition.