title: Hardness and microstructural variation of Al-Mg-Mn-Sc-Zr alloy.
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 Al3Sc1-xZrx and also block-shaped Al3Sc precipitates growing along <100>Al with facets {100} and {110} 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 Al3Sc.
authors.affiliation: Department of Materials Science and Engineering, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.
authors.forename: Sumiha
authors.initials: S
authors.lastname: Ikeshita
authors.affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.
authors.forename: Ansis
authors.initials: A
authors.lastname: Strodahs
authors.affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.
authors.forename: Zineb
authors.initials: Z
authors.lastname: Saghi
authors.affiliation: Department of Materials Science and Engineering, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Centre Interdisciplinaie de Microscopie Electronique, Ecole Polytechniaue Fédérale de Lausanne (EPFL), Station 12, Lausanne 1015, Switzerland.
authors.forename: Pierre
authors.initials: P
authors.lastname: Burdet
authors.affiliation: Department of Electrical and Materials Science, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hata
authors.affiliation: Department of Electrical and Materials Science, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan.
authors.forename: Ken-Ichi
authors.initials: KI
authors.lastname: Ikeda
authors.affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Midgley
authors.affiliation: Department of Materials Science and Engineering, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan. Electronic address: kaneko@zaiko.kyushu-u.ac.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kaneko
keywords: Al alloy; Al(3)Sc; Al(3)Sc(1−x)Zr(x); EDX tomography; Precipitation hardening; Transmission electron microscopy