The present invention provides aluminum alloys and layers formed in aluminum alloys as well as methods for their manufacture. Aluminum alloys of the present invention are provided with at least one discrete layer of uncrystallized grains formed therein. Alloys of the present invention can be formed, for example, by a process that includes a final partial anneal that permits softening of the material to essentially an 0-temper condition. Processes of the present invention recrystallize substantially the entire material but leave a discrete layer of preferably less than 50 microns of the material unrecrystallized. In preferred embodiments, the aluminum material is a core material that is clad on one or both sides and the discrete unrecrystallized layer forms at the boundary between the clad and the core.