| 摘要 |
PURPOSE:To obtain the heat exchanger which is excellent in low temperature corrosion resistance and to prevent the fin from being closed up by a corrosion product by brazing and joining a tube made of iron and a fin made of Al at a specific temperature through a specific brazing filler metal. CONSTITUTION:A tube 1 made of iron and a fin 2 made of Al are brazed and joined at a temperature of <=570 deg.C through an Al - Si - high Zn compound brazing filler metal 24. In such a way, heat exchanger for hot-water supply in which an intermetallic compound layer of brittle FeAl3, etc., is not generated in the joint interface, or it is suppressed is obtained. Also, by covering the tube 1 with an Ni or Cr layer 7 in advance, generation of the intermetallic compound layer is further suppressed. |
