| 摘要 |
PURPOSE:To improve the corrosion resistance of a Cu or Cu alloy tube without deteriorating the heat transfer characteristics by forming an amorphous metallic film on the inner surface of the tube contacting with a corrosive medium. CONSTITUTION:An amorphous metallic film is formed on the inner surface of a heat exchanger tube of Cu or a Cu alloy to prevent the corrosion of the inner surface contacting with a corrosive medium such as seawater or hot water. The amorphous metallic film is a film of Ni-P, Ni-B or Ni-P-B formed by electroless nickel plating or a film of Fe-Cr-P, Fe-Cr-B or other alloy formed by electroplating. The amorphous metallic film maintains stably the amorphous state up to about 200-300 deg.C with slight deterioration in the heat transfer characteristics of the tube. When the tube is used in piping for supplying hot water, the bluing of water or other trouble can be prevented. |
