Thermomechanical processing of a twin-roll cast Al–1Fe–0.2Si alloy

A sound homogenization practice is identified for a twin-roll cast Al–1Fe–0.2Si (AA8079) alloy, a popular foil stock with a higher Fe/Si ratio than most other AlFeSi commercial alloys. Homogenization below 793 K produces a very fine dispersion of αc particles which in turn yields a very coarse and heterogeneous grain structure upon interannealing. When the Al–1Fe–0.2Si strip is homogenized above 833 K, αc particles are replaced by relatively coarser Al3Fe particles with a favorable effect on the recrystallized grain size. It is thus concluded that a homogenization temperature of at least 833 K must be employed to obtain a coarse particle dispersion which in turn would produce a fine grain size after interannealing.