| 摘要 |
PURPOSE:To form a lubricating film which has an excellent property of following a new surface produced by the working and hardly causes dragging of a mold and seizing, by forming a lubricating film on the surface of a metallic material by electrocoating prior to hot forging. CONSTITUTION:Prior to hot forging of metallic materials such as steel for machine structure, stainless steel, titanium and various alloys, a lubricating film contg. a water- soluble or water-dispersible electrocoating resin having a polar group which dissociates into ions in an aq. solution, e.g., a resin, such as acrylic resin or melamine resin, which has a polar group such as a COOH or NH2 group and becomes water soluble or water-dispersible and exhibits electrophoresis when it is neutralized with a suitable acid or a base and, e.g. lubricating solid powder such as talc or graphite is formed on the metallic material. Thus, the above process enables the formation of a lubricating film which exhibits excellent lubricating properties at a temperature ranging from 300-800 deg.C, has an excellent property of following a new surface produced by the working and hardly causes dragging of a mold and seizing, which enables hot forging of a metallic material to be easily conducted and, at the same time, improves the mold life. |
