| 摘要 |
PURPOSE:To prevent the contact between water and an aluminum body material and prolong the corrosion resistance life, by forming a zinc-diffused layer on the inner surface of a tube made of aluminum, together with a water resistant resin film thereon. CONSTITUTION:On the inner surface of a tube 1 made of aluminum, a zinc-diffused layer 12 is formed whose diffusion depth into the aluminum body material is the order of more than 10mu. On said diffued layer 12, a water resistant resin film 13, such as vinyl chloride-vinyl acetate copolymer or the like having a film thickness of more than 3mu is formed. |
