Metallurgical Abstracts on Light Metals and Alloys vol.55
Effect of pre-deformation on age-hardening behaviors in an Al-Mg-Cu alloy
Xuanliang Chen*, Daehan Kim**, Minho O*, Calin D. Marioara***, Sigmund J. Andersen***, Adrian Lervik****, Randi Holmestad**** and Equo Kobayashi*
*Department of Materials Science and Engineering, Tokyo Institute of Technology, 2-12-1-S8-18, Ookayama, Meguro-ku, Tokyo, 152-8552, Japan
**Carbon & Light Materials Application Group, Korea Institute of Industrial Technology, 222 Palbok-ro, Jeonju-si, 54896, South Korea
***Materials and Nanotechnology, SINTEF Industry, Høgskoleringen 5, N-7465, Trondheim, Norway
****Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, N-7491, Trondheim, Norway
[Published in Materials Science and Engineering: A, Vol. 820 (2021), pp. 141557]
https://doi.org/10.1016/j.msea.2021.141557
E-mail: equo[at]mtl.titech.ac.jp
Key Words: Aluminum alloys, Phase transformation, Hardness, Thermal analysis, Electron microscopy
The effects of 3%–50% pre-deformation following solution heat treatment on the age hardening of an Al-3Mg-1Cu alloy have been investigated by Vickers microhardness measurement, tensile tests, differential scanning calorimetry, scanning electron microscopy, and transmission electron microscopy. Pre-deformation has a strong effect on subsequent age-hardening behavior. The precipitation was accelerated, hardness peaks appeared earlier, formation of clusters was inhibited, and a larger fraction of precipitates was observed along the dislocation lines. The contribution of the precipitates to the hardness was evaluated by dissolution tests. It was found that pre-deformation followed by artificial aging resulted in a good strength-elongation balance. The results are significant for the development of combined mechanical deformation and heat treatment processes.
Pre-deformation hinders the first hardening but promotes the second hardening until peak. Two types of S phases were observed to form along a dislocation line.