Hardness and microstructural variation of Al–Mg–Mn–Sc–Zr alloy. (March 2016)

• Record Type: Journal Article
• Authors: Ikeshita, Sumiha; Strodahs, Ansis; Saghi, Zineb; Yamada, Kazuhiro; Burdet, Pierre; Hata, Satoshi; Ikeda, Ken-ichi; Midgley, Paul A.; Kaneko, Kenji
• Is Part Of: Micron. Volume 82(2016:Mar.)
• Page Start: 1
• Page End: 8
• Publication Date: 2016-03
• Subjects: Precipitation hardening -- Transmission electron microscopy -- EDX tomography -- Al alloy -- Al3Sc -- Al3Sc1−xZrx; Microscopy -- Periodicals; Electron Probe Microanalysis -- Periodicals; Microscopy -- Periodicals; Microscopie -- Périodiques; Microscopy; Periodicals; 502.82
• DOI: 10.1016/j.micron.2015.12.002
• Languages: English
• ISSNs: 0968-4328

Abstract

Highlights: Vickers hardness and microstructures of intragranular particles in Al–Mg–Mn–Sc–Zr alloy were examined as a function of the ageing period. Vickers hardness was increased by formation of block-shaped Al3 Sc precipitates growing along <1 0 0>Al with {1 0 0} and {1 1 0} of the precipitates. Microstructural characterizations confirmed the formation and growth of block-shaped Al3 Sc precipitates associated with ageing period. Abstract: Variations of Vickers hardness were observed in Al–Mg–Mn alloy and Al–Mg–Mn–Sc–Zr alloy at different ageing times, ranging from a peak value of 81.2 HV at 54 ks down to 67.4 HV at 360 ks, below the initial hardness value, 71.8 HV at 0 ks for the case of Al–Mg–Mn–Sc–Zr alloy. Microstructures of samples at each ageing stage were examined carefully by transmission electron microscopes (TEMs) both in two-dimensions and three-dimensions. The presence of different types, densities, and sizes of particles were observed dispersed spherical Al3 Sc1− x Zr x and also block-shaped Al3 Sc precipitates growing along <1 0 0>Al with facets {1 0 0} and {1 1 0} of the precipitates. TEM analysis both in two-dimensions and three-dimensions, performed on various samples, confirmed the direct correlation between the hardness and the density of Al3 Sc.