A tribologically modified polyoxymethylene polymer composition is disclosed. The polyoxymethylene polymer composition is comprised of a polyoxymethylene polymer and at least one tribological modifier. The tribological modifier may comprise at least one tribological modifier comprising an ultra-high molecular weight silicone having a kinematic viscosity of greater than 100,000 mm.sup.2 s.sup.1. The composition may exhibit a dynamic coefficient of friction against a counter-material of from about 0.01 to about 0.15. The polyoxymethylene polymer compositions provide polymer articles with improved tribological properties and mechanical properties.

A water-based lubricant for plastic working of a metallic material is obtained by adding to a water-based medium: (A) a polymer and/or a salt thereof containing a carboxylic acid or a derivative thereof as a constituent monomer; (B) an oxoacid of tungsten, of silicon, or of phosphorus, or a condensate thereof, and/or a salt thereof; (C) a hydroxide of an alkali metal; and (D) a lubricating component (D), and the solid content weight ratio (A)/[(A)+(B)+(C)+(D)] is 0.05 to 0.4.

A water-based lubricant for plastic working of a metallic material is obtained by adding to a water-based medium: (A) a polymer and/or a salt thereof containing a carboxylic acid or a derivative thereof as a constituent monomer; (B) an oxoacid of tungsten, of silicon, or of phosphorus, or a condensate thereof, and/or a salt thereof; (C) a hydroxide of an alkali metal; and (D) a lubricating component (D), and the solid content weight ratio (A)/[(A)+(B)+(C)+(D)] is 0.05 to 0.4.

A device includes a tribological assembly including first and second mechanical components in relative motion with respect to each other, the assembly having a silver-alloy surface and an additive lubricant including at least one component of the formulas (Ia) or (II): M.sub.xNO.sub.y (Ia), where M is Ca, V, Sb, Ni, or Ag, x (M:N ratio) is any number between 0.25 and 2, and y (O:N ratio) is any number between 1 and 8; M.sub.xSiO.sub.y (II), where M is Mg or Al, x (M:Si ratio) is any number between 0.5 and 2, and y (O:Si ratio) is any number between 2.5 and 6, the device being a sealed constant-pressure device.

A device includes a tribological assembly including first and second mechanical components in relative motion with respect to each other, the assembly having a silver-alloy surface and an additive lubricant including at least one component of the formulas (Ia) or (II): M.sub.xNO.sub.y (Ia), where M is Ca, V, Sb, Ni, or Ag, x (M:N ratio) is any number between 0.25 and 2, and y (O:N ratio) is any number between 1 and 8; M.sub.xSiO.sub.y (II), where M is Mg or Al, x (M:Si ratio) is any number between 0.5 and 2, and y (O:Si ratio) is any number between 2.5 and 6, the device being a sealed constant-pressure device.

A lubricant for a copper alloy die-casting die is mainly prepared by an inorganic nano-powder, an organic substrate material, and an organic resin material. In the present disclosure, the use of oil-based lubricants as a basis and the reduction of the content of oil in the lubricant yield improved oil selection and proportion, which cooperates with the corresponding higher proportion of inorganic powder material mixture and a more suitable spraying amount applied on the surface of the die to exert a good lubricating effect on products with complex and irregular shapes in the inner cavity of a die-casting die. At the same time, the production cost of the lubricant is low. Copper alloy die castings produced after a lubrication process have a high yield rate and smooth surfaces without casting defects.

A lubricant for a copper alloy die-casting die is mainly prepared by an inorganic nano-powder, an organic substrate material, and an organic resin material. In the present disclosure, the use of oil-based lubricants as a basis and the reduction of the content of oil in the lubricant yield improved oil selection and proportion, which cooperates with the corresponding higher proportion of inorganic powder material mixture and a more suitable spraying amount applied on the surface of the die to exert a good lubricating effect on products with complex and irregular shapes in the inner cavity of a die-casting die. At the same time, the production cost of the lubricant is low. Copper alloy die castings produced after a lubrication process have a high yield rate and smooth surfaces without casting defects.

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.

Fuels, hydraulic fluids and lubricants made of or comprising a portion of renewable hydrocarbon raw materials, as well as biodegradable fuels, hydraulic fluids and lubricants are known to support microbial growth. Highly toxicorganic biocides have been added to reduce microbial growth. The use of such biocides can now be avoided, by instead using a stable solution of boric acid in a solvent, the boric acid being completely dissolved or at least free from any particles larger than 100 nm in size, and adding this solution to the fuel, hydraulic fluid or lubricant to give a final concentration of boron in the range of 1-100 ppm, preferably 1-50 ppm in the product. While preventing microbial growth, the addition of boron also reduces corrosion, in particular microbiologically induced corrosion (MIC).