Vacuum-brazing aluminum cladding material consisting of Al or Al alloy core and two superposed aluminum alloy clads which cover at least one surface of the core

A vacuum-brazing aluminum cladding material consisting of a core member of aluminum or aluminum alloy, and a first clad and a second clad formed on said first clad, which first and second clads cover at least one of opposite surfaces of said core member, said first clad consisting essentially of 6-14% by weight of Si, 0-0.6% by weight of Mg and the balance being at least Al, said second clad consisting essentially of 0-14% by weight of Si, 0.8-2.5% by weight of Mg and the balancing being at least Al, said second clad having a thickness of at least 5 .mu.m, and said thickness and a content of Si of said second clad being determined so as to satisfy the following formula:

• t.ltoreq..vertline.100/(10-c).vertline.
• wherein,
• t=thickness (.mu.m) of said second clad;
• and
• c=content (% by weight) of Si of said second clad.