| 摘要 |
PROBLEM TO BE SOLVED: To provide a joined body of aluminum tubes in which the preferential corrosion of a brazed part is prevented, and the corrosion resistance of a joint is excellent.SOLUTION: Provided is a joint body of aluminum tubes using a plurality of aluminum tubes provided with either a straight part or a flare part on both the edge parts, in which adjoining either straight part and the other flare part are engaged, and an Al-Si based brazing filler metal is arranged therebetween, and brazing is performed. At least the aluminum tube provided with the straight part being an aluminum-clad tube obtained by cladding an Al-Zn sacrificial layer comprising 0.5 to 1.5% Zn on the outer surface of the core material of an Al alloy comprising 0.8 to 1.3% Mn and 0.4 to 0.8% Cu, a molten diffused part with a semi-spherical solidified structure where an Al-Si based brazing filler metal corrodes the Al-Zn sacrificial layer is formed on the straight part of the joint, and the thickness of the molten diffused part is 0.5 to 2.0 times the clad thickness of the Al-Zn sacrificial layer. |
