The invention relates to a method for manufacturing an aluminum/metal assembly including the steps involving: thermally processing an aluminum sheet by heating said sheet to a temperature of between 80% and 100% of the melting temperature of the material of which it consists for a sufficiently long duration to create and stabilize by allotropic conversion an alpha alumina layer at the surface of said aluminum sheet, and then cooling same; providing a metal layer having a ductility less than or equal to the ductility of the aluminum sheet after cooling, said layer having surface irregularities having a depth greater than or equal to the thickness of the alpha alumina layer; and roll bonding the aluminum layer and the metal layer to produce the metal assembly.