| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a joining method by which penetration leakage is not caused in an early stage by preventing the preferred corrosion of a torch brazed part. <P>SOLUTION: In the joining method by which two tube materials each formed by providing a clad layer of pure Al having ≥99.5 wt.% purity and ≤0.5% impurities having ≤0.25 wt.% Si, ≤0.40 wt.% Fe and the rest of inevitable impurities on an outer surface of a core material made of an Al alloy are prepared, an end part of one tube material is expanded and the other tube material is inserted in the expanded tube part to join the both tube materials by torch brazing, a brazing material used for torch brazing is an Al alloy having 11.0 to 13.0 wt.% Si, 1.0 to 2.0 wt.% Zn and the rest of inevitable impurities and torch brazing is retained for 3 to 8 sec after reaching 600°C. <P>COPYRIGHT: (C)2011,JPO&INPIT |
