ALUMINUM ALLOY-BRAZING SHEET FOR HEAT EXCHANGER HAVING EXCELLENT BRAZABILITY AND CORROSION RESISTANCE, AND HEAT EXCHANGER TUBE HAVING EXCELLENT CORROSION RESISTANCE

摘要

PROBLEM TO BE SOLVED: To provide an aluminum alloy-brazing sheet for a heat exchanger tube in which brazability and corrosion resistance at the internal face of a tube when being made into a heat exchanger tube are made consistent.;SOLUTION: Regarding the aluminum alloy brazing sheet for a heat exchanger tube, in an aluminum alloy core material 2, the face so as to be the external side of the tube is coated with a first aluminum alloy brazing filler metal 3 composed of an Al-Si based hypoeutectic alloy comprising, by mass, 5 to 12% Si, and the face so as to be the internal side of the tube is coated with a second aluminum alloy brazing filler metal 4 comprising, by mass, 2.1 to 5.0% Si, 0.2 to 7.0% Zn, 0.05 to 0.75% Mn, and the balance Al with inevitable impurities. The brazing sheet exhibits satisfactory brazability by the second aluminum alloy brazing filler metal so as to be the surface layer of the internal face of the tube, and further exhibits satisfactory corrosion resistance since suitable eutectic phases are almost uniformly present in the facial direction.;COPYRIGHT: (C)2008,JPO&INPIT