Composite aluminium alloy sheet for heat exchangers - comprises aluminium core coated with alloy of aluminium, zinc and lithium, calcium, sodium or potassium

摘要

The composite sheet is made of a core of Al alloy one or both surfaces being provided with a plated coat of an Al alloy of compsn. 0.1-2.0 wt.% Zn, 0.01-2.0 wt.% Li, Ca, Na or K, balance Al. The sheet is produced by applying the plating material to the surface of a bar of the Al alloy, which is then hot and cold rolled to sheet. Used for the fabrication of heat exchangers by vacuum brazing. The plated coat has a thickness of 3-20% of the total thickness of the composite. The composite sheet can be vacuum brazed without the loss of Zn due to evaporation.