NOVELTY - An aqueous lubricant composition comprises 5-35 wt.% powder lubrication agent, 0.5-5 wt.% film-forming agent, and 5 wt.% or less surfactant. The powder lubrication agent comprises wax having melting point of 120-170 degrees C and average particle diameter measured by laser diffraction of 20 mu m or less. The film-forming agent contains water-soluble polymer(s) chosen from polyvinyl alcohol, polyvinylpyrrolidone, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, polyacrylic acid polymer and polymeric polysaccharide.    USE - Aqueous lubricant composition is used for forming metal processing material (claimed) for battery housing.    ADVANTAGE - The lubrication agent composition does not deteriorate work environment by generation of powder dust, and provides metal processing material with suppressed fracture and surface flaws, and excellent workability. The lubrication agent residue can be washed by a simple method after coating. The lubrication agent composition provides battery housing which does not cause bad influence with respect to battery characteristics.    DETAILED DESCRIPTION - An aqueous lubricant composition comprises 5-35 wt.% powder lubrication agent, 0.5-5 wt.% film-forming agent, and 5 wt.% or less surfactant. The powder lubrication agent comprises wax having melting point of 120-170 degrees C and average particle diameter measured by laser diffraction of 20 mu m or less. The film-forming agent contains water-soluble polymer(s) chosen from polyvinyl alcohol, polyvinylpyrrolidone, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, polyacrylic acid polymer and polymeric polysaccharide. The powder lubrication agent, film-forming agent and surfactant does not contain metallic element. INDEPENDENT CLAIMS are included for the following:    (1) metal processing material, which has solid lubricous film formed by applying lubrication agent composition on a metal work piece, impact pressing, and evaporating 2-20 g/m2 water content from the formed film, on the surface; and    (2) coating method, which involves heating metal processing material at 50-100 degrees C, contacting with lubrication agent composition, and forming solid lubricous film on the surface of the metal processing material when water content evaporates from the lubrication agent composition by remaining heat of the metal processing material.