• Atomic structures of precipitates in Al–Mg–Si alloys with small additions of other elements 

      Saito, Takeshi; Mørtsell, Eva Anne; Wenner, Sigurd; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Friis, Jesper; Matsuda, Kenji; Holmestad, Randi (Peer reviewed; Journal article, 2018)
      In Al–Mg–Si alloys, additions of only a few weight percent of Mg and Si enable formation of hardening precipitates during heat treatment. The precipitation is complex and is influenced by chemical compositions and ...
    • Atomistic details of precipitates in lean Al–Mg–Si alloys with trace additions of Ag and Ge studied by HAADF-STEM and DFT 

      Mørtsell, Eva Anne; Andersen, Sigmund Jarle; Friis, Jesper; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2017)
      Bonding energies and volume misfits for alloying elements and vacancies in multicomponent Al–Mg–Si alloys have been calculated using density functional theory (DFT). A detailed atomic scale analysis has been done for ...
    • The effect of Cu and Ge additions on strength and precipitation in a lean 6xxx aluminium alloy 

      Mørtsell, Eva Anne; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Røyset, Jostein; Reiso, Oddvin; Holmestad, Randi (Peer reviewed; Journal article, 2015)
      It has been demonstrated that the strength loss in a lean Al-Mg-Si alloy due to solute reduction could be compensated by back-adding a lower at % of Ge and Cu. Nanosized precipitate needles which are the main cause of ...
    • The effects and behaviour of Li and Cu alloying agents in lean Al-Mg-Si alloys 

      Mørtsell, Eva Anne; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Ringdalen, Inga Gudem; Friis, Jesper; Wenner, Sigurd; Røyset, Jostein; Reiso, Oddvin; Holmestad, Randi (Peer reviewed; Journal article, 2016)
      We show how replacing a fraction of Mg with Li in a lean Al-Mg-Si alloy gives comparable strength and enhanced temperature stability. Replacing solute with smaller amounts of Cu and Li also improves thermal stability and ...
    • Effects of Germanium, Copper, and Silver Substitutions on Hardness and Microstructure in Lean Al-Mg-Si Alloys 

      Mørtsell, Eva Anne; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Røyset, Jostein; Reiso, Oddvin; Holmestad, Randi (Peer reviewed; Journal article, 2015)
      It is shown that strength loss in a 6060 Al-Mg-Si alloy caused by reduction in solute can be compensated by adding back smaller quantities of Ag, Ge, and Cu. Nine alloys were investigated. Ge was found to be the most ...
    • Elemental electron energy loss mapping of a precipitate in a multi-component aluminium alloy 

      Mørtsell, Eva Anne; Wenner, Sigurd; Longo, Paulo; Andersen, Sigmund Jarle; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2016)
      The elemental distribution of a precipitate cross section, situated in a lean Al-Mg-Si-Cu-Ag-Ge alloy, has been investigated in detail by electron energy loss spectroscopy (EELS) and aberration corrected high angle annular ...
    • Enhanced Mechanical Properties in 6082 Aluminum Alloy Processed by Cyclic Deformation 

      Chen, Xuanliang; Mørtsell, Eva Anne; Sunde, Jonas Kristoffer; O, Minho; Marioara, Calin Daniel; Holmestad, Randi; Kobayashi, Equo (Peer reviewed; Journal article, 2021)
      Aging heat treatment is the most commonly used strengthening method for Al–Mg–Si alloys since high-density precipitates will be formed to hinder the movement of dislocations. In the current work, room temperature cyclic ...
    • Improving ageing kinetics and precipitation hardening in an Al-Mg-Si alloy by minor Cd addition 

      Qian, Feng; Mørtsell, Eva Anne; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Li, Yanjun (Peer reviewed; Journal article, 2018)
      This study reports significant improvements in both the age hardening kinetics and peak hardness of an Al-Mg-Si alloy by microalloying with 0.06 at% Cd. A detailed high-angle annular dark-field scanning transmission electron ...
    • Precipitation in an A356 foundry alloy with Cu additions - A transmission electron microscopy study 

      Mørtsell, Eva Anne; Qian, Feng; Marioara, Calin Daniel; Li, Yanjun (Peer reviewed; Journal article, 2019)
      The influence of different Cu addition levels on the age hardening and precipitation behaviors in an Al356 foundry alloy during artificial aging treatment has been systematically studied. A detailed characterization of the ...
    • The Effect of Elastic Strain and Small Plastic Deformation on Tensile Strength of a Lean Al–Mg–Si Alloy 

      Mørtsell, Eva Anne; Westermann, Ida; Marioara, Calin Daniel; Pedersen, Ketill Olav; Andersen, Sigmund Jarle; Røyset, Jostein; Holmedal, Bjørn; Holmestad, Randi (Journal article; Peer reviewed, 2019)
      Al–Mg–Si alloys are usually formed into their final shape by rolling or extrusion. After extrusion, the aluminium profiles are usually straightened, causing the material to be subjected to a small plastic deformation. This ...