Blar i Institutt for materialteknologi på forfatter "Andersen, Sigmund Jarle"
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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 (Journal article; Peer reviewed, 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 (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 ... -
Directionality and column arrangement principles of precipitates in Al-Mg-Si-(Cu) and Al-Mg-Cu linked to line defect in Al
Andersen, Sigmund Jarle; Marioara, Calin Daniel; Friis, Jesper; Bjørge, Ruben; Du, Qiang; Ringdalen, Inga Gudem; Wenner, Sigurd; Mørtsell, Eva Anne; Holmestad, Randi; Saito, Takeshi; Røyset, Jostein; Reiso, Oddvin (Journal article, 2016)In the structures of all metastable precipitates in Al-Mg-Cu and Al-Mg-Si alloys, we find that column surrounding of an element column in the needle/lath direction order according to simple principles. Advanced transmission ... -
Enhanced nucleation and precipitation hardening in Al-Mg-Si(-Cu) alloys with minor Cd additions
Qian, Feng; Zhao, Dongdong; Mørtsell, Eva Anne; Jin, Shenbao; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Sha, Gang; Li, Yanjun (Peer reviewed; Journal article, 2020)This work reports a novel effect of impurity element Cd on enhancing the precipitation kinetics and increasing the peak hardness of Al–Mg–Si(–Cu) alloys during artificial ageing. It is found that the number density of age ... -
The evolution of precipitates in an Al–Zn–Mg alloy
Thronsen, Elisabeth; Shah, Sohail; Hatzoglou, Constantinos; Marioara, Calin Daniel; Wenner, Sigurd; Andersen, Sigmund Jarle; Holmedal, Bjørn; Holmestad, Randi (Peer reviewed; Journal article, 2023)The precipitation sequence in Al–Zn–Mg alloys has been subject to many revisions over the years as more structural details of the early-stage Guinier-Preston (GP) zones and precipitates have been uncovered. To further ... -
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 (Journal article; Peer reviewed, 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 ... -
Modeling over-ageing in Al-Mg-Si alloys by a multi-phase CALPHAD-coupled Kampmann-Wagner Numerical model
Du, Qiang; Tang, Kai; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmedal, Bjørn; Holmestad, Randi (Journal article, 2017)The formation of the equilibrium precipitation phase during ageing treatment of Al-Mg-Si alloys is preceded by a series of metastable phases. Given longer ageing time, higher ageing temperature or elevated temperature ... -
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 ... -
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. ...