Composite aluminium sheet

摘要

This invention relates to a method of making a composite aluminium brazing sheet, which method comprises: providing a core sheet of a first Al alloy and a cladding sheet of a second Al alloy, wherein a) the composition of the first Al alloy is different from the composition of the second Al alloy, b) the thickness of the core sheet is greater than the thickness of the cladding sheet, and c) the hardness of the core sheet is different than the hardness of the cladding sheet, cleaning facing surfaces of the core sheet and of the cladding sheet; and cold rolling the core sheet with the cladding sheet so as to roll bond them to make a composite aluminium sheet. Also disclosed is a brazing sheet comprising a core layer of a first Al alloy containing Mg and a cladding layer of a second Al alloy.