Blar i SINTEF Open på forfatter "Marioara, Calin Daniel"

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    • The Effect of Deformation and Isothermal Heat Treatment of a 5005 Aluminum Alloy 

      Holmestad, Jon; Marioara, Calin Daniel; Myrold, Benedikte Jørgensen; Jensrud, Ola (Peer reviewed; Journal article, 2024)
      In the aluminum industry, forming is an important process step that introduces dislocations in the material. To investigate the effect of dislocation retention after ageing on 6xxx-series alloys, a non-heat-treatable 5005 ...

    • 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 effect of low Cu additions on precipitate crystal structures in overaged Al-Mg-Si(-Cu) alloys 

      Sunde, Jonas Kristoffer; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2020)
      This study concerns the effect of low Cu additions (<0.1 at.%) on the precipitate crystal structure evolution in three Al-Mg-Si(-Cu) alloys during overageing. The evolution was assessed through a combination of atomic ...

    • 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, ...

    • 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 (Peer reviewed; Journal article, 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 ...

    • 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 ...

    • Effects of Germanium, Copper, and Silver Substitutions on Hardness and Microstructure in Lean Al-Mg-Si Alloys 

      Mørtsell, Eva Anne; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Røyset, Jostein; Reiso, Oddvin; Holmestad, Randi (Peer reviewed; Journal article, 2015)
      It is shown that strength loss in a 6060 Al-Mg-Si alloy caused by reduction in solute can be compensated by adding back smaller quantities of Ag, Ge, and Cu. Nine alloys were investigated. Ge was found to be the most ...

    • The Effects of Low Cu Additions and Predeformation on the Precipitation in a 6060 Al-Mg-Si Alloy 

      Saito, Takeshi; Muraishi, Shinji; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Jostein, Røyset; Holmestad, Randi (Peer reviewed; Journal article, 2013)
      Effects of low Cu additions (≤0.10 wt pct) and 10 pct predeformation before aging on precipitates’ microstructures and types in a 6060 Al-Mg-Si alloy have been investigated using transmission electron microscopy (TEM). It ...

    • The effects of quench rate and pre-deformation on precipitation hardening in Al–Mg–Si alloys with different Cu amounts 

      Saito, Takeshi; Marioara, Calin Daniel; Røyset, Jostein; Marthinsen, Knut; Holmestad, Randi (Peer reviewed; Journal article, 2014)
      The effects of quench rate after solution heat treatment in combination with 1% pre-deformation on precipitation hardening in three Al–Mg–Si alloys have been investigated by transmission electron microscopy and hardness ...

    • Elemental electron energy loss mapping of a precipitate in a multi-component aluminium alloy 

      Mørtsell, Eva Anne; Wenner, Sigurd; Longo, Paulo; Andersen, Sigmund Jarle; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2016)
      The elemental distribution of a precipitate cross section, situated in a lean Al-Mg-Si-Cu-Ag-Ge alloy, has been investigated in detail by electron energy loss spectroscopy (EELS) and aberration corrected high angle annular ...

    • Enhanced Mechanical Properties in 6082 Aluminum Alloy Processed by Cyclic Deformation 

      Chen, Xuanliang; Mørtsell, Eva Anne; Sunde, Jonas Kristoffer; O, Minho; Marioara, Calin Daniel; Holmestad, Randi; Kobayashi, Equo (Peer reviewed; Journal article, 2021)
      Aging heat treatment is the most commonly used strengthening method for Al–Mg–Si alloys since high-density precipitates will be formed to hinder the movement of dislocations. In the current work, room temperature cyclic ...

    • 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 ...

    • An experimental study on pre-stretched double-chamber 6000-series aluminium profiles subjected to quasi-static and dynamic axial crushing 

      Qvale, Kristin; Hopperstad, Odd Sture; Reiso, Oddvin; Tundal, Ulf; Marioara, Calin Daniel; Børvik, Tore (Peer reviewed; Journal article, 2020)
      Automotive crash boxes require a material selection with strength and ductility in a balanced combination. In this work, the behaviour of double-chamber AA6063 and AA6082 aluminium profiles subjected to quasi-static and ...

    • Grain boundary structures and their correlation with intergranular corrosion in an extruded Al-Mg-Si-Cu alloy 

      Lervik, Adrian; Wenner, Sigurd; Lunder, Otto; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2020)
      A detailed analysis of grain boundaries in a highly textured Al-Mg-Si-Cu alloy is presented in this work. Electron backscatter diffraction demonstrates the presence of three main categories of grain boundaries in addition ...

    • Hot Deformation and Die-Quenching of 6000-Series Alloys—The Effect of Quench-Interruption Temperature 

      Pettersen, Tanja; Myrold, Benedikte Jørgensen; Marioara, Calin Daniel; Jensrud, Ola (The Minerals, Metals & Materials Series;2367-1696, Chapter; Peer reviewed, 2020)
      The automotive industry face demands to produce lightweight vehicles and substituting steel with aluminium is a straightforward solution. Age hardenable aluminium alloys are attractive candidates when the aim is a combination ...

    • How calcium prevents precipitation hardening in Al–Mg–Si alloys 

      Wenner, Sigurd; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmestad, Randi (Peer reviewed; Journal article, 2013)
      We have investigated the effect on precipitate microstructure and hardness upon adding small amounts of Ca to a base Al–Mg–Si alloy. The main investigative techniques were transmission and scanning electron microscopy. We ...

    • A hybrid aluminium alloy and its zoo of interacting nano-precipitates 

      Wenner, Sigurd; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Ervik, Martin; Holmestad, Randi (Peer reviewed; Journal article, 2015)
      An alloy with aluminium as its base element is heat treated to form a multitude of precipitate phases known from different classes of industrial alloys: Al–Cu(–Mg), Al–Mg–Si–Cu, and Al–Zn–Mg. Nanometer-sized needle-shaped ...

    • An improved modelling framework for strength and work hardening of precipitate strengthened Al–Mg–Si alloys 

      Lu, Feng; Sunde, Jonas Kristoffer; Marioara, Calin Daniel; Holmestad, Randi; Holmedal, Bjørn (Peer reviewed; Journal article, 2022)
      A modelling framework for the strength and work hardening contributions in age hardened Al–Mg–Si alloys is presented. The modelling work is based on transmission electron microscopy (TEM) measurements of the needle-shaped ...

    • 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 (Peer reviewed; Journal article, 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 ...

    • Influence of natural aging and ramping before artificial aging on the microstructure of two different 6xxx alloys 

      Hell, Christoph Martin; Søreide, Hanne-Sofie Marie Scisly; Bjørge, Ruben; Marioara, Calin Daniel; Li, Yanjun; Holmestad, Randi (Peer reviewed; Journal article, 2022)
      In this study the effect of a ramp up to artificial aging (AA) temperature in combination with natural aging (NA) was analyzed for two different industrial aluminium alloys. The alloys differ in their Mg/Si ratio as well ...