| 摘要 |
PURPOSE:To manufacture a heat exchanger whose corrosion resistance is satisfactory, a simple process, by depositing Zn on the surface of a heat exchanger member bofore brazing is performed, and also applying a flux consisting of potassium fluoroaluminate. CONSTITUTION:On the surface of a heat exchanger member constituted of an Al material, Zn is deposited by 0.5-20g/m<2>, preferably 5-15g/m<2> by a chemical plating method, etc. using an alkaline solution of ZnO, and after that, a slurry- like flux consisting of about 1pt. of a mixture of KAlF4 and K3AlF6 whose particle size is about 100 meshes or less, and 2pts. of water is applied in the ratio of about 2-5g/m<2>, and subsequently, brazing is performed at a temperature of about 580-620 deg.C by use of a brazing material consisting of an Al-Si alloy of about 4.5-13.5% Si whose melting point is lower than that of the Al material. In this case, it is desirable that brazing is performed in a non-oxidizing atmosphere. |
