| abstract |
An aqueous lubricant for use in plastic working of a metallic material which comprises (A) a water soluble inorganic salt and (B) a wax, wherein the components are dissolved or dispersed in water, and wherein a solid concentration ratio (weight ratio). (B)/(A) is 0.3-1.5. and a method for producing a lubricative film, characterized in that a lubricative film is produced by applying the aqueous lubricant, preferably in a dried weight of 0.5-40g/m2, on the surface of a metallic material, providing no chemical conversion layer thereon, followed by drying. The aqueous lubricant preferably further comprises (C) a metal salt of a fatty acid in a solid concentration ratio (C /(A) of 0.01-0.4. The water soluble inorganic salt is preferably selected from among a sulfate, a silicate, a borate, a molybdate and a tungstate. The wax is preferably a synthetic wax which is dispersed in water and has a melting point of 70^150. The metal salt of a fatty acid (C) is preferably obtained through reacting a saturated fatty acid having 12-26 carbon atoms with a metal selected from among zinc, calcium, barium, aluminium, magnesium and lithium. The aqueous lubricant can be used for imparting excellent lubricity with ease to the surface of metal having no chemical conversion layer formed thereon. |