A method for preparing a super-lubricative multi-layer composite fullerene-like carbon layer/graphene-like boron nitride thin film is provided. A substrate is ultrasonically cleaned in absolute ethyl alcohol and acetone sequentially for 15 min. The substrate is cleaned by argon plasma bombardment for 15 min. A fullerene-like carbon layer A having an onion-like structure is prepared by high-vacuum medium-frequency magnetron sputtering for 30 s. A graphene-like boron nitride layer B is prepared by high-vacuum medium-frequency magnetron sputtering and coating device to sputter the elemental boron target for 30 s. Steps (3) and (4) are repeated 80 times to overlay the fullerene-like carbon layer A and the graphene-like boron nitride layer B in an alternate way. The super-lubricative multi-layer composite fullerene-like carbon layer/graphene-like boron nitride thin film has a large load capacity, and excellent wear resistance, high temperature resistance and super lubrication.

A strain wave gearing has contact parts which are the portions to be lubricated other than the teeth of an externally toothed gear and an internally toothed gear, the contact parts being respectively lubricated with an inorganic lubricating powder having a lamellar crystal structure. The lubricating powder, during the operation of the strain wave gearing, is crushed between the contact surfaces of each of the contact parts to move and adhere to the contact surfaces, thereby forming thin surface films thereon. Additionally, the powder is thinly spread by pressure and reduced into finer particles to change into a shape which facilitates intrusion into the space between the contact surfaces. By both the fine particles having changed in shape and the surface films, the lubrication of the contact parts is maintained. Neither the fine particles nor the surface films are viscous.

A strain wave gearing has contact parts which are the portions to be lubricated other than the teeth of an externally toothed gear and an internally toothed gear, the contact parts being respectively lubricated with an inorganic lubricating powder having a lamellar crystal structure. The lubricating powder, during the operation of the strain wave gearing, is crushed between the contact surfaces of each of the contact parts to move and adhere to the contact surfaces, thereby forming thin surface films thereon. Additionally, the powder is thinly spread by pressure and reduced into finer particles to change into a shape which facilitates intrusion into the space between the contact surfaces. By both the fine particles having changed in shape and the surface films, the lubrication of the contact parts is maintained. Neither the fine particles nor the surface films are viscous.

To provide a method for producing a hot forged material in air, using a Ni-based super alloy for the die, which is advantageous in terms of the service life of the die, and using a glass-based lubricant which hardly causes any chemical reaction promoting oxidative corrosion. A method for producing a hot forged material, by placing on a lower die a material for hot forging, of which part or all of the surface is coated with a glass-based lubricant, and pressing the material for hot forging with the lower die and an upper die, to form a hot forged material, wherein one or both of the lower die and the upper die are made of a Ni-based superalloy, and wherein the surface of the die in contact with the material for hot forging is coated with a glass-based lubricant containing SiO.sub.2 as a main component, in which the total content of alkali metal oxides is 0 to 10.0% in mass %.

A method involves the coating of a metallic substrate with a blasting medium through sandblasting or equivalent techniques. The blasting medium is preferably a powder made of silicon nitride (or other ceramic or engineering materials). The sandblasting process allows the silicon nitride powder to form a loosely packed layer on the substrate. With additional treatment via rolling and/or sliding action against a secondary body in the presence of a liquid lubricant, the loosely packed particle layer turns into a flattened surface matrix consisting of particle clusters and irregular cavities. The silicon nitride particles are spontaneously attached to the substrate surface without the use of an adhesive agent which subsequently leads to the formation of a surface matrix exhibiting a chaotic hybrid topography with zero tensile stress when subjected to rolling/sliding contact pressure. This cluster-cavity matrix can evolve continuously (thus dynamic) and is immune to debris indentation from dirty lubricants. It is a complex, self organizing, and adaptive system. The practical value of this invention is to greatly enhance the fatigue and wear life of the bearing substrate and other objects coming into contact with the treated substrate.

A method involves the coating of a metallic substrate with a blasting medium through sandblasting or equivalent techniques. The blasting medium is preferably a powder made of silicon nitride (or other ceramic or engineering materials). The sandblasting process allows the silicon nitride powder to form a loosely packed layer on the substrate. With additional treatment via rolling and/or sliding action against a secondary body in the presence of a liquid lubricant, the loosely packed particle layer turns into a flattened surface matrix consisting of particle clusters and irregular cavities. The silicon nitride particles are spontaneously attached to the substrate surface without the use of an adhesive agent which subsequently leads to the formation of a surface matrix exhibiting a chaotic hybrid topography with zero tensile stress when subjected to rolling/sliding contact pressure. This cluster-cavity matrix can evolve continuously (thus dynamic) and is immune to debris indentation from dirty lubricants. It is a complex, self organizing, and adaptive system. The practical value of this invention is to greatly enhance the fatigue and wear life of the bearing substrate and other objects coming into contact with the treated substrate.

Disclosed herein is a method of using a water-based coolant for quenching or cutting a metal material. The water-based coolant is formed of: water; at least one inorganic acid salt selected from the group consisting of a carbonate, a hydrogen carbonate, a sesquicarbonate, a phosphate, a borate, a molybdate and a tungstate; a metal corrosion inhibitor; and optionally at least one of a bactericide, a water-soluble rust inhibitor, an antioxidant and a detergent dispersant.

Disclosed herein is a method of using a water-based coolant for quenching or cutting a metal material. The water-based coolant is formed of: water; at least one inorganic acid salt selected from the group consisting of a carbonate, a hydrogen carbonate, a sesquicarbonate, a phosphate, a borate, a molybdate and a tungstate; a metal corrosion inhibitor; and optionally at least one of a bactericide, a water-soluble rust inhibitor, an antioxidant and a detergent dispersant.

A novel hydraulic fluid composition for application to drilling equipment is described herein. These hydraulic fluid compositions permit effective monitoring or controlling well-head pressure of a well during drilling on land or offshore. The hydraulic fluid compositions prevent uncontrolled flow of gas, oil, or another well fluid out of an underground formation during a drilling or extraction process when applied to the drilling equipment. Accordingly, provided is a hydraulic fluid concentrate which contains a water-soluble phosphate ester and a sulfide compound containing at least one SS linkage, at least 10 carbon atoms and at least one terminal carboxylate group, wherein the SS linkage bridges two alkyl groups. Additional components can be added to the concentrate and include one or more alkaline compound, one or more dicarboxylic acid or salt thereof, a water-soluble corrosion inhibitor, a water-soluble biocide, a pour point depressant, and water, ethylene glycol, or a combination thereof. The concentrate is then further diluted by the customer for use as described herein. Particularly, these compositions are effective in reducing seawater corrosion of a metal in contact with the hydraulic fluid composition, reducing bioaccumulation in oil drilling equipment contacted with the hydraulic fluid composition, and have low toxicity to sea life.

A novel hydraulic fluid composition for application to drilling equipment is described herein. These hydraulic fluid compositions permit effective monitoring or controlling well-head pressure of a well during drilling on land or offshore. The hydraulic fluid compositions prevent uncontrolled flow of gas, oil, or another well fluid out of an underground formation during a drilling or extraction process when applied to the drilling equipment. Accordingly, provided is a hydraulic fluid concentrate which contains a water-soluble phosphate ester and a sulfide compound containing at least one SS linkage, at least 10 carbon atoms and at least one terminal carboxylate group, wherein the SS linkage bridges two alkyl groups. Additional components can be added to the concentrate and include one or more alkaline compound, one or more dicarboxylic acid or salt thereof, a water-soluble corrosion inhibitor, a water-soluble biocide, a pour point depressant, and water, ethylene glycol, or a combination thereof. The concentrate is then further diluted by the customer for use as described herein. Particularly, these compositions are effective in reducing seawater corrosion of a metal in contact with the hydraulic fluid composition, reducing bioaccumulation in oil drilling equipment contacted with the hydraulic fluid composition, and have low toxicity to sea life.