Recrystallisation Resistance of Extruded and Cold Rolled Aluminium Alloys with Additions of Hf, Sc and Zr
A high recrystallisation resistance is required in aluminium alloys intended for processing or use at temperatures between 450°C-600°C. Additions of Hf, Sc and Zr significantly improve the resistance to recrystallisation through the formation of Al3X-dispersoids (X=Hf,Sc,Zr), and in this work different concentrations and combinations of these elements were added to five aluminium alloys. The alloys were extruded, subjected to various degrees of cold rolling (0%-80%) and finally annealed at high temperatures in order to study the structural stability. All variants displayed a high resistance towards recrystallisation, but the best results were obtained in the alloy containing only Sc and Zr. In this alloy no signs of recrystallisation were observed even after 1 hour annealing of extruded and 80% cold rolled profiles at 600°C.
W.J. Poole, M.A. Wells and D.J. Lloyd
H. Hallem et al., "Recrystallisation Resistance of Extruded and Cold Rolled Aluminium Alloys with Additions of Hf, Sc and Zr", Materials Science Forum, Vols. 519-521, pp. 525-530, 2006