Blar i NTNU Open på forfatter "Holmestad, Randi"
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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 ... -
Dispersion hardening during annealing at low Temperatures in four 3xxx Al-Mn-Fe-Si Alloys
Mørtsell, Eva Anne (Master thesis, 2012)3xxx aluminiumslegeringer har Mangan som hovedlegeringselement, og får sin styrke fra plastisk bearbeidelse. 3xxx legeringer har tidligere blitt ansett for å oppnå neglisjerbare endringer i hardhet og styrke som følge av ... -
e-DREAM: the European Distributed Research Infrastructure for Advanced Electron Microscopy
Ciancio, Regina; Dunin-Borkowski, Rafal E.; Snoeck, Etienne; Kociak, Matheiu; Holmestad, Randi; Verbeeck, Johan; Kirkland, Angus I.; Kothleitner, Gerald; Arbiol, Jordi (Peer reviewed; Journal article, 2022) -
Edge interfaces of the Ω plates in a peak-aged Al-Cu-Mg-Ag alloy
Gazizov, Marat; Boev, A.O.; Marioara, Calin Daniel; Holmestad, Randi; Gazizova, M.Yu.; Kaibyshev, Rustam (Journal article; Peer reviewed, 2022)The coherent edge interface structures of the relatively thin {111}Al Ω plates have been analyzed in a peak-aged Al-Cu-Mg-Ag alloy by atomic-resolution scanning transmission electron microscopy (STEM). Analysis of STEM ... -
EELS and STEM studies of perovskite oxide heterostructures
Nord, Magnus (Doctoral theses at NTNU;2016:361, Doctoral thesis, 2016)Perovskite oxide heterostructures have attracted much research interest due to a strong coupling between the local crystal structure and the functional properties. Of special interest are the interfaces of thin film systems, ... -
Effect of Copper Addition on Precipitation Behavior near Grain Boundary in Al-Zn-Mg Alloy
Matsuda, Kenji; Yasumoto, Toru; Bendo, Artenis; Tsuchiya, Taiki; Lee, Seungwon; Nishimura, Katsuhiko; Nunomura, Norio; Marioara, Calin Daniel; Lervik, Adrian; Holmestad, Randi; Toda, Hiroyuki; Yamaguchi, Masatake; Ikeda, Ken-ichi; Homma, Tomoyuki; Ikeno, Susumu (Journal article; Peer reviewed, 2019)The effect of Cu-addition on age-hardening and precipitation have been investigated by hardness measurement, tensile test, high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning ... -
Effect of copper addition on the cluster formation behavior of Al-Mg-Si, Al-Zn-Mg, and Al-Mg-Ge in the natural aging
Hatakeyama, Daichi; Nishimura, Katsuhiko; Matsuda, Kenji; Namiki, Takahiro; Lee, Seungwon; Nunomura, Norio; Aida, Tetsuo; Matsuzaki, Teiichiro; Holmestad, Randi; Wenner, Sigurd; Marioara, Calin Daniel (Journal article; Peer reviewed, 2018)The time-dependent resistivity of Al-Mg-Si(-Cu), Al-Zn-Mg(-Cu), and Al-Mg-Ge(-Cu) alloys are studied over a range of constant temperatures between 255 K and 320 K. The resistivity vs time curves for the samples show three ... -
Effect of copper on fine precipitates at the early stage of aging in Al-Mg-X (X=Si, Ge, Zn) alloys
Matsuda, Kenji; Kawai, Akihiro; Watanabe, Katsumi; Lee, Seungwon; Marioara, Calin Daniel; Wenner, Sigurd; Nishimura, Katsuhiko; Matsuzaki, Teiichiro; Nunomura, Norio; Sato, Tatsuo; Holmestad, Randi; Ikeno, Susumu (Journal article, 2017)Age-hardenable Al–Mg–Si, Al–Mg–Ge, and Al–Zn–Mg alloys including Cu were investigated by transmission electron microscopy to understand extra diffraction spots that appear in their selected area electron diffraction patterns. ... -
Effect of cyclic ageing on the early-stage clustering in Al–Zn-Mg(-Cu) alloys
Shah, Sohail; Thronsen, Elisabeth; Hatzoglou, Constantinos; Wenner, Sigurd; Marioara, Calin Daniel; Holmestad, Randi; Holmedal, Bjørn (Peer reviewed; Journal article, 2022)The cyclic application of mechanical stress to aluminum alloys at room temperature, referred to as cyclic ageing, continuously injects vacancies, enabling dynamic precipitation of a fine distribution of solute clusters. ... -
The effect of deformation and natural ageing in an Al-Mg-Si-Cu alloy with high Cu-content: A transmission electron microscopy study
Thronsen, Elisabeth (Master thesis, 2018)The effect of the combination of natural ageing and deformation to 80 % on precipitation in an Al-Mg-Si-Cu alloy has been investigated by different transmission electron microscopy (TEM) techniques. Similar research is ... -
The Effect of Elevated Temperatures on Precipitation in Aluminium Alloys – An Advanced Transmission Electron Microscopy Study
Sunde, Jonas Kristoffer (Doctoral theses at NTNU, 2020:229, Doctoral thesis, 2020)Aluminium (Al) alloys are increasingly found and sought-after in applications that involve exposure to elevated temperatures. Examples are automotive components located in the engine room, heat exchangers, and subsea/offshore ... -
Effect of low Cu addition and thermo-mechanical history on precipitation in Al-Mg-Si alloys
Saito, Takeshi; Marioara, Calin Daniel; Røyset, Jostein; Holmestad, Randi (Journal article, 2014)The effect of cooling rate after solution heat treatment and its combination with 1% pre-deformation on precipitation hardening in two Al-Mg-Si alloys is investigated by transmission electron microscopy (TEM), and related ... -
Effect of Multiply Twinned Ag(0) Nanoparticles on Photocatalytic Properties of TiO2 Nanosheets and TiO2 Nanostructured Thin Films
Bakardjieva, Snejana; Mares, Jakub; Koci, Eva; Tolasz, Jakub; Fajgar, Radek; Ryukhtin, Vasyl; Klementova, Mariana; Michna, Štefan; Bibova, Hanna; Holmestad, Randi; Titorenkova, Rositsa; Čaplovičová, Mária (Peer reviewed; Journal article, 2022)Ag-decorated TiO2 nanostructured materials are promising photocatalysts. We used non-standard cryo-lyophilization and ArF laser ablation methods to produce TiO2 nanosheets and TiO2 nanostructured thin films decorated with ... -
Effect of Natural Ageing on an Al-Cu-Mg-Si Alloy: A Transmission Electron Microscopy Study
Thrane, Elisabeth Savitri (Master thesis, 2022)Effekten av naturlig elding på utfelling av presipitater i en udeformert Al-Cu-Mg-Si legering ble undersøkt ved ulike teknikker i transmisjonselektronmikroskopi (TEM). Målet med studiet var å relatere presipitatstatistikk, ... -
The effect of natural ageing on clustering and precipitation in heat-treatable aluminium alloys
Thronsen, Elisabeth (Doctoral theses at NTNU;2022:274, Doctoral thesis, 2022)The consumption volume of aluminium (Al) alloys is expected to increase in the coming years. They are typically used in the automotive industry, where light-weighting has become a major design consideration to save fuel, ... -
Effect of Natural Ageing Temperature and Time on Precipitation in 6xxx Aluminium Alloys
Lervik, Petter (Master thesis, 2022)Hovedformålet med dette MSc prosjektet er å undersøke påvirkningen av temperatur i mellomlagrings-leddet på 6xxx aluminium (Al) serien. Familien av 6xxx Al legeringer er vist å nå et platå i hardhet som er avhengig av ... -
Effect of polar (111)-oriented SrTiO3 on initial perovskite growth
Hallsteinsen, Ingrid; Nord, Magnus Kristofer; Bolstad, Torstein; Vullum, Per Erik; Boschker, Jos Emiel; Longo, Paulo; Takahashi, Ryota; Holmestad, Randi; Lippmaa, Mikk; Tybell, Per Thomas Martin (Journal article, 2016)In crystalline thin film growth a prerequisite is substrate surfaces with a stable and uniform structure and chemical composition. Various substrate treatments were used to obtain atomically smooth, step-and-terrace ... -
Effect of pre-deformation on age-hardening behaviors in an Al-Mg-Cu alloy
Chen, Xuanliang; Daehan, Kim; O, Minho; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Lervik, Adrian; Holmestad, Randi; Kobayashi, Equo (Peer reviewed; Journal article, 2021)The effects of 3%–50% pre-deformation following solution heat treatment on the age hardening of an Al-3Mg-1Cu alloy have been investigated by Vickers microhardness measurement, tensile tests, differential scanning calorimetry, ... -
Effect of room temperature storage time on precipitation in Al-Mg-Si(-Cu) alloys with different Mg/Si ratios
Wenner, Sigurd; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmestad, Randi (Journal article; Peer reviewed, 2012)The effect of natural ageing time before artificial ageing has been investigated in four Al – Mg – Si(– Cu) alloys, with 0.4 % Mg + 0.8 % Si and 0.8 % Mg + 0.4 % Si, both with and without 0.14 at.% Cu. The precipitate ... -
The Effect of Small Additions of Fe and Heavy Deformation on the Precipitation in an Al–1.1Mg–0.5Cu–0.3Si At. Pct Alloy
Thronsen, Elisabeth; Mørkeseth, Hanne; Marioara, Calin Daniel; Minakuchi, Kazuhiro; Katsumi, Tetsuya; Marthinsen, Knut; Matsuda, Kenji; Holmestad, Randi (Journal article; Peer reviewed, 2022)The effect of 0.03 and 0.08 at. pct Fe additions on the formation of secondary phases in an Al–1.1Mg–0.5Cu–0.3Si at. pct alloy was investigated. Following solution heat treatment and natural aging, the alloys were analyzed ...