Method for making aluminum alloy strips with high surface homogeneity

N NNN NN N A process for manufacturing a strip of aluminum alloy having high surface homogeneity with an upper side showing after a 1 μm thick sulphur anodic treatment, an optical roughness value Smeasured on three 5 cm longitudinal sections and three 5 cm transverse sections, such that its mean variation on each section, defined by the ratio: (Maximum S−minimum S)/Mean Sis less than 20%, and the difference ΔS=Smax −Smin is less than 20. The strip is manufactured by continuous casting between two cooled rolls from a casting tank containing the liquid metal connected to an injector, and feeding the liquid metal into the gap between the two rolls. The injector has an upper lip recessed by at least 2 mm with reference to a lower lip of the injector.