| 摘要 |
PURPOSE:To render bolt set high corrosion resistance, easiness of painting, good lubricativity, and high co-turning inhibition by the procedure in which a metal phosphate film is formed on the surface of bolt and nut, a film composed of a vehicle and chromium oxide is formed further on the metal phosphate film, and an inorganic paint film is applied on washer. CONSTITUTION:A 0.1 to 50 g/m<2> zinc or Mn phosphate film is applied on the base surface of bolt and also a 0.1 to 50 g/m<2> paint film composed primarily of an under coat vehicle and Cr oxide is applied on the phosphate film layer. A 0.1 to 50 g/m<2> film the same as that for the bolt is applied on the base surface of nut and then a paint film composed primarily of a vehicle, Cr oxide, and a lubricant, e.g., a higher fatty acid metal salt, etc., is likewise applied on the under film. And, for washer, a 100 to 1000 g/m<2> zinc-rich paint film composed primarily of zinc powder is applied or a phosphate film is coated on the base surface and also a paint film composed primarily of a vehicle, Cr oxide, and quartz is coated on the under coat. The combined application of the three coating methods is effectively used for the junctions of structures. |
