Now showing items 21-37 of 37

    • Modelling the Age-Hardening Precipitation by a Revised Langer and Schwartz Approach with Log-Normal Size Distribution 

      Zhao, Dongdong; Xu, Yijiang; Gouttebroze, Sylvain; Friis, Jesper; Li, Yanjun (Peer reviewed; Journal article, 2020)
      A new numerical modelling approach integrating the Langer and Schwartz approach and log-normal particle size distribution has been developed to depict the precipitation kinetics of age-hardening precipitates in Al alloys. ...
    • Modelling the evolution in microchemistry and its effects on the softening behavior of cold rolled AlFeMnSi-alloys during annealing 

      Hersent, Emmanuel C; Huang, Ke; Friis, Jesper; Marthinsen, Knut (Journal article, 2013)
      A dedicated diffusion controlled precipitation model for AlMnFeSi-alloys, based on classical nucleation and growth theory, has been implemented and coupled to a phenomenological softening model accounting for the combined ...
    • Modelling time-dependent nucleation of recrystallization in aluminium alloys 

      Marthinsen, Knut; Friis, Jesper; Engler, Olaf (Journal article; Peer reviewed, 2013)
      The basic equations and mathematical framework of a mean-field model for recovery and recrystallization, the latter based on the Johnson-Mehl-Avrami-Kolmogorov (JMAK) approach, capable of handling time-dependent nucleation ...
    • 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, FeAl, FeAl, FeAl, FeAl, FeAl) have been studied using modified embedded atom method (MEAM) potentials. The equilibrium lattice constants, formation enthalpies, ...
    • 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 ...
    • 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 ...
    • Precipitates in aluminium alloys 

      Andersen, Sigmund Jarle; Marioara, Calin Daniel; Friis, Jesper; Wenner, Sigurd; Holmestad, Randi (Journal article; Peer reviewed, 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 (Peer reviewed; Journal article, 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 ...
    • Precipitation behavior in an Al-Cu-Mg-Si alloy during ageing 

      Gazizov, Marat; Marioara, Calin Daniel; Friis, Jesper; Wenner, Sigurd; Holmestad, Randi; Kaibyshev, Rustam (Peer reviewed; Journal article, 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 ...
    • Precipitation in a mixed Al-Cu-Mg/Al-Zn-Mg alloy system 

      Wenner, Sigurd; Friis, Jesper; Marioara, Calin Daniel; Holmestad, Randi (Journal article, 2016)
      The precipitation-hardened alloy systems Al–Cu–Mg (2xxx) and Al–Zn–Mg (7xxx) were compositionally combined from a base alloy containing 2% Cu and 1% Mg, added 1–4% Zn (weight fractions). Precipitates in these alloys were ...
    • Quantitative Convergent Beam Electron Diffraction and Charge Density Studies 

      Friis, Jesper (Dr. ingeniøravhandling, 0809-103X; 2003:97, Doctoral thesis, 2003)
      Very accurate low-order structure factors have been measured in copper, magnesium and strontium titanate using quantitative convergent beam electron diffraction (QCBED). The charge density distribution in these materials ...
    • Structural modifications and electron beam damage in aluminium alloy precipitate θ'-Al2Cu 

      Wenner, Sigurd; Friis, Jesper; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmestad, Randi (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 ...
    • 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 (Journal article; Peer reviewed, 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 ...
    • 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 (Journal article; Peer reviewed, 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 (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 ...
    • Topology-based construction of business-integrated material modelling workflows 

      Preisig, Heinz A.; Klein, Peter; Konchakova, Natalia; Hagelien, Thomas Fjæstad; Friis, Jesper; Horsch, Martin Thomas (Chapter, 2022)
      Designing a new product requires information from the business and physical domains, which implies integrating business decision tools with process and material simulation processes to form an overall workflow. The integration ...
    • α-Mg primary phase formation and dendritic morphology transition in solidification of a Mg-Nd-Gd-Zn-Zr casting alloy 

      Casari, Daniele; Mirihanage, Wajira; Falch, Ken Vidar; Ringdalen, Inga Gudem; Friis, Jesper; Schmid-Fetzer, Rainer; Zhao, Dongdong; Li, Yanjun; Sillekens, Wim H.; Mathiesen, Ragnvald (Journal article; Peer reviewed, 2016)
      Microstructure evolution in the commercial Mg-Nd-Gd-Zn-Zr alloy Elektron 21, solidified under nearly isothermal conditions, has been studied via in-situ X-ray radiography. For cooling rates View the MathML source≤0.075 ...