• Atomic structure of clusters and GP-zones in an Al-Mg-Si alloy 

      Marioara, Calin Daniel; Andersen, Sigmund Jarle; Hell, Christoph Martin; Frafjord, Jonas; Friis, Jesper; Bjørge, Ruben; Ringdalen, Inga Gudem; Engler, Olaf; Holmestad, Randi (Peer reviewed; Journal article, 2024)
      The structures of atomic clusters and GP-zones preceding precipitation in an Al-0.70Mg-0.85Si-0.15Fe-0.25Mn (wt. %) alloy have been investigated by annular dark field scanning transmission electron microscopy imaging and ...
    • First principle calculations of pressure dependent yielding in solute strengthened aluminium alloys 

      Frafjord, Jonas; Ringdalen, Inga Gudem; Hopperstad, Odd Sture; Holmestad, Randi; Friis, Jesper (Peer reviewed; Journal article, 2020)
      The pressure dependence of the yield stress in solute strengthened aluminium alloys is investigated by first principle calculations. The solute elements studied are magnesium, silicon and copper. A fixed boundary cluster ...
    • Fully resolved strain field of the β’’ precipitate calculated by density functional theory 

      Frafjord, Jonas; Dumoulin, Stephane; Wenner, Sigurd; Ringdalen, Inga Gudem; Holmestad, Randi; Friis, Jesper (Peer reviewed; Journal article, 2020)
      The β′′ precipitate is the main hardening phase in age hardenable Al-Mg-Si alloys, and it is therefore of major scientific and industrial importance. A full model of the β′′ precipitate cross-section embedded in an aluminium ...
    • On the Atomic Structure of the β′′ Precipitate by Density Functional Theory 

      Frafjord, Jonas; Ringdalen, Inga Gudem; Holmestad, Randi; Friis, Jesper (Peer reviewed; Journal article, 2023)
      The substitution of elements into the precipitate in the 6xxx-series of aluminium alloys is an interface sensitive problem. The strain caused by the misfit between the precipitate and the matrix interacts with the size ...
    • On the visibility of GP-zones in 6xxx Al alloys in atomic LAADF-STEM 

      Hell, Christoph Martin; Frafjord, Jonas; Bjørge, Ruben; Friis, Jesper; Holmestad, Randi (Peer reviewed; Journal article, 2024)
      In this work, the contrast seen in low-angle annular dark-field (LAADF) scanning transmission electron microscopy (STEM) of Guinier-Preston zones (GP-zones) in Al-Mg-Si alloys (6xxx) is discussed by STEM simulations, ...
    • Studying GPI zones in Al-Zn-Mg alloys by 4D-STEM 

      Thronsen, Elisabeth; Frafjord, Jonas; Friis, Jesper; Marioara, Calin Daniel; Wenner, Sigurd; Andersen, Sigmund Jarle; Holmestad, Randi (Peer reviewed; Journal article, 2021)
      A new methodology has been developed to study the fine details of GP zones in age-hardenable aluminium alloys. It is complementary to atomic resolution high-angle annular dark-field scanning transmission electron microscopy ...