Blar i SINTEF Open på forfatter "Marioara, Calin Daniel"
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Scanning Precession Electron Diffraction to aid Aluminum Alloy Development
Sunde, Jonas Kristoffer; Christiansen, Emil; Thronsen, Elisabeth; Wenner, Sigurd; Marioara, Calin Daniel; Van Helvoort, Antonius; Holmestad, Randi (Peer reviewed; Journal article, 2019) -
Stress Corrosion Cracking in an Extruded Cu-Free Al-Zn-Mg Alloy
Lervik, Adrian; Walmsley, John Charles; Lodgaard, Lars; Marioara, Calin Daniel; Johnsen, Roy; Lunder, Otto; Holmestad, Randi (Peer reviewed; Journal article, 2020)Stress corrosion cracking (SCC) in Cu-free Al-Zn-Mg (7xxx) aluminium alloys limits its use in many applications. In this work, we study in detail the microstructure of a peak and slightly overaged condition in an AA7003 ... -
Structural investigation of precipitates with Cu and Zn atomic columns in Al-Mg-Si alloys by aberration-corrected HAADF-STEM
Saito, Takeshi; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Lefebvre, Williams; Holmestad, Randi (Peer reviewed; Journal article, 2014)Precipitates in Al-Mg-Si alloys with Cu addition (~0.1 wt%) and Zn addition (~1 wt%) were investigated by aberration corrected high angle annular dark field scanning transmission electron microscopy (HAADF-STEM). Most ... -
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 ... -
A study of the influence of precipitate free zones on the strain localization and failure of the aluminium alloy AA7075-T651
Fourmeau, Marion; Marioara, Calin Daniel; Børvik, Tore; Benallal, Ahmed; Hopperstad, Odd Sture (Peer reviewed; Journal article, 2015)Age-hardened aluminium alloys have various degrees of precipitate-free zones (PFZs) along grain boundaries (GBs). The PFZs are weak zones and their existence promotes combined transgranular and intergranular fracture, thus ... -
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 ... -
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 evolution of precipitate crystal structures in an Al-Mg-Si(-Cu) alloy studied by a combined HAADF-STEM and SPED approach
Sunde, Jonas Kristoffer; Marioara, Calin Daniel; Van Helvoort, Antonius; Holmestad, Randi (Journal article; Peer reviewed, 2018)This work presents a detailed investigation into the effect of a low Cu addition (0.01 at.%) on precipitation in an Al-0.80Mg-0.85Si alloy during ageing. The precipitate crystal structures were assessed by scanning ... -
A transmission electron microscopy study of precipitate phases that form during operation in a heat exchanger alloy
Marioara, Calin Daniel; Friis, Jesper; Hersent, Emmanuel; Oskarsson, Anders (Peer reviewed; Journal article, 2019)During manufacturing of heat exchangers, the core material is cladded with a lower-melting point alloy, rolled into thin strips before being formed and finally brazed at an elevated temperature. After a period of natural ... -
The unique hybrid precipitate in a peak-aged Al-Cu-Mg-Ag alloy
Gazizov, Marat; Boev, A.O.; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmestad, Randi; Kaibyshev, Rustam; Aksyonov, D.A.; Krasnikov, V.S. (Peer reviewed; Journal article, 2021)The prevalent hardening phase forming in an Al-Cu-Mg-Ag alloy after peak-aging at 150 and 190 °C has been investigated using transmission electron microscopy methods. The precipitate atomic structure was determined. It is ... -
µSR study of Al-0.67%Mg-0.77%Si alloys
Nishimura, Katsuhiko; Matsuda, Kenji; Komaki, R; Nunomura, Norio; Wenner, Sigurd; Holmestad, Randi; Matsuzaki, Teiichiro; Watanabe, Isao; Pratt, Francis L.; Marioara, Calin Daniel (Peer reviewed; Journal article, 2014)Zero-field muon spin relaxation measurements were carried out with Al-0.67%Mg- 0.77%Si alloys in the temperature range from 20 K to 300 K. Observed relaxation spectra were compared with the relaxation functions calculated ...