Aluminum alloy brazing sheet for vacuum brazing exhibiting excellent corrosion resistance, and heat exchanger using the brazing sheet

摘要

An aluminum alloy brazing sheet has a quad-layer structure made of an outer filler material, intermediate layer material, core material, and inner filler material. The core material contains 0.5-1.6% of Mn, 0.10-0.50% of Cu, 0.05-0.50% of Mg, and 0.06-0.30% of Ti, and, as impurities, 0.5% or less of Fe, 0.5% or less of Si, and 0.1% or less of Zn, with the remainder being Al and unavoidable impurities; the intermediate layer material contains 0.2-1.5% of Mg and at least one of 0.5-4% of Zn, 0.005-0.2% of In, and 0.01-0.2% of Sn, and, as impurities, 0.3% or less of Si, 0.3% or less of Fe, 0.05% or less of Cu, 0.05% or less of Mn, and 0.3% or less of Ti, with the remainder being Al and unavoidable impurities. The thickness of the intermediate layer material is 50 &mgr;m or more and no more than the thickness of the core material. The outer filler material and the inner filler material are Al—Si—Mg alloys, the outer filler material, preferably including at least one of 0.005-0.2% of In and 0.01-0.2% of Sn.