• The atomic simulation environment - A Python library for working with atoms 

      Larsen, Ask Hjorth; Mortensen, Jens Jørgen; Blomqvist, Jakob; Castelli, Ivano E.; Christensen, Rune; Dulak, Marcin; Friis, Jesper; Groves, Michael N.; Hammer, Bjørk; Hargus, Cory; Hermes, Eric D.; Jennings, Paul C.; Jensen, Peter Bjerre; Kermode, James; Kitchin, John R.; Kolsbjerg, Esben Leonhard; Kubal, Joseph; Kaasbjerg, Kristen; Lysgaard, Steen; Maronsson, Jón Bergmann; Maxson, Tristan; Olsen, Thomas; Pastewka, Lars; Peterson, Andrew; Rostgaard, Carsten; Schiøtz, Jakob; Schütt, Ole; Strange, Mikkel; Thygesen, Kristian S.; Vegge, Tejs; Vilhelmsen, Lasse; Walter, Michael N.; Zeng, Zhenhua; Jacobsen, Karsten Wedel (Peer reviewed; Journal article, 2017)
      Abstract The Atomic Simulation Environment (ASE) is a software package written in the Python programming language with the aim of setting up, steering, and analyzing atomistic simula- tions. In ASE, tasks are fully scripted ...
    • Atomic structure of solute clusters in Al-Zn-Mg alloys 

      Lervik, Adrian; Thronsen, Elisabeth; Friis, Jesper; Marioara, Calin Daniel; Wenner, Sigurd; Bendo, Artenis; Matsuda, Kenji; Holmestad, Randi; Andersen, Sigmund Jarle (Peer reviewed; Journal article, 2020)
      Scanning transmission electron microscopy imaging of Al–Zn–Mg alloys has provided new information on the atomic structures of solute rich clusters forming from a supersaturated solid solution at low temperatures. A unique ...
    • 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 approach to simulate kink migration and kink-pair formation in silicon: The kinetic activation-relaxation technique 

      Eliassen, Simen Nut Hansen; Friis, Jesper; Ringdalen, Inga Gudem; Mousseau, Normand; Trochet, Mickaël; Li, Yanjun (Peer reviewed; Journal article, 2019)
      The energy conversion efficiency of solar cells based on multicrystalline silicon is greatly deteriorated by dislocations. However, an in-depth understanding on the dislocation motion dynamics down to atomic scale is still ...
    • 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 ...
    • Data on atomic structures of precipitates in an Al-Mg-Cu alloy studied by high resolution transmission electron microscopy and first-principles calculations 

      Chen, Xuanliang; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Friis, Jesper; Lervik, Adrian; Holmestad, Randi; Kobayashi, Equo (Peer reviewed; Journal article, 2021)
    • The effect of heavy deformation on the precipitation in an Al-1.3Cu-1.0Mg-0.4Si wt.% alloy 

      Thronsen, Elisabeth; Marioara, Calin Daniel; Sunde, Jonas Kristoffer; Minakuchi, Kazuhiro; Katsumi, Tetsuya; Erga, Iven; Andersen, Sigmund Jarle; Friis, Jesper; Marthinsen, Knut; Matsuda, Kenji; Holmestad, Randi (Peer reviewed; Journal article, 2020)
      This work has investigated the effect of the combination of natural ageing and 80% pre-deformation after solution heat treatment on precipitation during subsequent artificial ageing in an Al-1.3Cu-1.0Mg-0.4Si wt.% alloy. ...
    • 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 ...
    • 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 ...
    • First-principles study of tensile and shear strength of an Fe2Al5//Fe interface 

      Khalid, Muhammad Zeeshan; Friis, Jesper; Ninive, Per Harald; Marthinsen, Knut; Ringdalen, Inga Gudem; Strandlie, Are (Peer reviewed; Journal article, 2021)
      First-principles virtual tensile and shear strength calculations have been performed on the Fe2Al5// Fe4Al13 and -AlFeSi// Fe4Al13 interfaces. The Fast Inertial Relaxation Engine (FIRE) algorithm is used for optimizing ...
    • 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 ...
    • Interoperability architecture for bridging computational tools: Application to steel corrosion in concrete 

      Mir, Zahid M.; Friis, Jesper; Hagelien, Thomas Fjæstad; Svenum, Ingeborg-Helene; Ringdalen, Inga Gudem; Konchakova, Natalia; Mikhail, Zheludkevich; Hoche, Daniel (Journal article; Peer reviewed, 2020-01-15)
      A multiscale modelling framework, especially for corrosion modelling, requires not only robust computational tools but also an efficient datacentric architecture for handling information exchange at different modelling ...
    • Modified embedded atom method potential for Fe-Al intermetallics mechanical strength: A comparative analysis of atomistic simulations 

      Khalid, Muhammad Zeeshan; Friis, Jesper; Ninive, Per Harald; Marthinsen, Knut; Ringdalen, Inga Gudem; Strandlie, Are (Peer reviewed; Journal article, 2021)
      The structural and mechanical properties of Fe-Al compounds (FeAl, Fe2Al, Fe3Al, FeAl2, FeAl3, Fe2Al5) have been studied using modified embedded atom method (MEAM) potentials. The equilibrium lattice constants, formation ...
    • Multi-scale Modelling of Titanium Diboride Degradation Using Crystal Elasticity Model and Density Functional Theory 

      Saai, Afaf; Wang, Zhaohui; Pezzotta, Micol; Friis, Jesper; Ratvik, Arne Petter; Vullum, Per Erik (The Minerals, Metals & Materials Series;2367-1181, Peer reviewed; Journal article, 2018)
      Titanium diboride (TiB2) is regarded as the most promising material to be used as inert cathodes in the electrochemical reduction of alumina to aluminium metal. TiB2 is well known as a ceramic material with high strength ...
    • On intermetallic phases formed during interdiffusion between aluminium alloys and stainless steel 

      Bergh, Tina; Arbo, Siri Marthe; Hagen, Anette Brocks; Blindheim, Jørgen; Friis, Jesper; Khalid, Muhammad Zeeshan; Ringdalen, Inga Gudem; Holmestad, Randi; Westermann, Ida; Vullum, Per Erik (Peer reviewed; Journal article, 2022)
      One of the major challenges in welding of aluminium (Al) alloys and steels is the growth of brittle intermetallic phases, which depends on the thermomechanical processing history and the alloying elements. This work focuses ...
    • Precipitates in aluminium alloys 

      Andersen, Sigmund Jarle; Marioara, Calin Daniel; Friis, Jesper; Wenner, Sigurd; Holmestad, Randi (Peer reviewed; Journal article, 2018)
      Precipitation strengthening is a highly complex phenomenon on the nanoscale, responsible for providing strength in Al-Cu, Al-Mg-Cu, Al-Mg-Zn and Al-Mg-Si alloys. Advances in methodology, especially high-angle annular ...
    • Precipitation behavior in an Al-Cu-Mg-Si alloy during ageing 

      Gazizov, Marat; Marioara, Calin Daniel; Friis, Jesper; Wenner, Sigurd; Holmestad, Randi; Kaibyshev, Rustam (Journal article; Peer reviewed, 2019)
      The precipitation behavior and aging response of an Al-4.9Cu-0.74Mg-0.51Si-0.48Mn-0.1Cr-0.08Ti-0.02Fe (wt. %) alloy was examined in detail after aging at 170 °C with different dwell times up to 96 h. Deformation by ...
    • The Role of Grain Boundary Precipitates during Intergranular Fracture in 6xxx Series Aluminium Alloys 

      Ringdalen, Inga Gudem; Jensen, Ingvild Julie Thue; Marioara, Calin Daniel; Friis, Jesper (Peer reviewed; Journal article, 2021)
      During ageing, 6xxx aluminium alloys will develop a microstructure characterised by needle-shaped Mg/Si-rich precipitates in the bulk, precipitate-free zones along the grain boundaries and larger Mg/Si-rich precipitates ...
    • Structural modifications and electron beam damage in aluminium alloy precipitate θ'-Al2Cu 

      Wenner, Sigurd; Friis, Jesper; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmestad, Randi (Peer reviewed; Journal article, 2015)
      The –AlCu phase in an Al–4Zn–2Cu–1Mg–0.7Si (wt.%) alloy was investigated by means of scanning transmission electron microscopy. With our specific alloy composition, the phase is often formed with stacking faults on and ...
    • Structure, hydration, and chloride ingress in C-S-H: Insight from DFT calculations 

      Svenum, Ingeborg-Helene; Ringdalen, Inga Gudem; Bleken, Francesca Lønstad; Friis, Jesper; Hoche, Daniel; Swang, Ole (Peer reviewed; Journal article, 2020)
      The structure of Calcium-Silicate-Hydrate (C-S-H) and the effect of variations in its water content have been investigated using density functional theory (DFT) calculations. Trends for calculated densities as a function ...