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, W.J. Rittel, B. Forbord, K. Marthinsen, "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