Patent ID: 9328977
Filing Date: 2016-05-03
CPC Classification: B23K,C22C,F28D,F28F,Y10T

Claim Text:
1. An aluminum alloy heat exchanger formed by a process comprising assembling and brazing an aluminum alloy tube and an aluminum alloy fin to each other, wherein a coating for brazing comprising 1 to 5 g/m the fin comprises aluminum and 0.8 to 2.0% by mass of Mn, Si in an amount of 1/2.5 to 1/3.5 of Mn content; less than 0.30% by mass of Fe, and Zn in an amount that is controlled in relation with the amount of the Zn containing flux in the coating for brazing to be in a region enclosed by points A, B, C, D, E and F of wherein a fillet comprising brazing filler of the coating for brazing is formed between the tube and the aluminum alloy fin which are in physical contact after the brazing; wherein a primary crystal portion that joins the fin and the tube is formed in the fillet; wherein a eutectic crystal portion is formed in a portion other than the primary crystal portion; and an electric potential of the primary crystal portion is set equal to or higher than an electric potential of the aluminum alloy fin.