Investigation of the Precipitation Kinetics of a New Al-Mg-Sc-Zr Alloy

Abstract:

This study investigates the precipitation behavior of two similar cast Al-Mg-Sc-Zr alloys with different solidification and cooling rates. Microstructural analyses and hardness testing were performed after casting and ageing. In addition, the precipitation and hardness evolution after rapid quenching using electron beam re-solidification were studied. It was shown that the amount of Al₃(Sc,Zr) phases present after casting or re-solidification increases with decreasing solidification and cooling rate. Consequently, the degree of supersaturation in Sc and Zr at room temperature and thus the hardening potential in a subsequent ageing process increases with the solidification and cooling rate. Therefore, the electron beam re-solidified samples revealed the most pronounced hardening.

• Periodical: Materials Science Forum (Volumes 794-796)
• Pages: 1038-1043
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.794-796.1038
• Online since: June 2014
• Authors: Johannes Taendl*, Frank Palm, Kevin Anders, Rudolf Gradinger, Maria Cecilia Poletti
• Keywords: Al-Sc Alloy, Electron Beam Welding, Precipitation Strengthening, Rapid Solidification

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