Multi-layer aluminium alloy brazing sheet

摘要

A core material (1) of an aluminum brazing sheet (4) restricts Mg to less than 0.3wt% and Fe to not more than 0.2wt%, and contains more than 0.2wt% and not more than 1.0wt% of Cu, 0.3 to 1.3wt% of Si, 0.3 to 1.5wt% of Mn and the balance of A1 and inevitable impurities. A brazing filler material (3) is formed on one surface of the core material (1) by Al-Si based aluminum alloy. Also, a cladding material (2) is formed on the other surface of the core material (1), and contains less than 0.2wt% of Si, 2.0 to 3.5wt% of Mg, not less than 0.5wt% and less than 2.0wt% of Zn and the balance of A1 and inevitable impurities. Further, the value (cladding material hardness)/(the core material hardness), that is the ratio of the hardness of the cladding material to the hardness of the core material, is not more than 1.5. <IMAGE>