• Carbonation of silica cement at high-temperature well conditions 

      Bjørge, Ruben; Gawel, Kamila; Chavez Panduro, Elvia Anabela; Torsæter, Malin (Journal article; Peer reviewed, 2019)
      Cements for well environments with temperatures above 110 °C are typically designed with silica additions. This is the case for many of the wells in the North Sea, which is a region promising for large-scale geological ...
    • Characterization and structure of precipitates in 6xxx Aluminium Alloys 

      Holmestad, Randi; Bjørge, Ruben; Ehlers, Flemming J H; Torsæter, Malin; Marioara, Calin Daniel; Andersen, Sigmund Jarle (Journal article; Peer reviewed, 2012)
      Solute atom nanoscale precipitates are responsible for the favourable mechanical properties of heat treatable aluminium alloys such as Al-Mg-Si (6xxx). The shape, structure and strengthening properties of age-hardening ...
    • Characterizing hardening on annealing of cold-rolled aluminum AA3103 strips 

      Govindaraj, Nagaraj Vinayagam; Bjørge, Ruben; Holmedal, Bjørn (Journal article; Peer reviewed, 2013)
      AA3103 aluminum strips were cold rolled to various von Mises strains up to 4.7. In addition, two severely deformed conditions were obtained by one and four cycles of cold accumulated roll bonding subsequent to cold rolling ...
    • Closing of Micro-cavities in Well Cement upon Exposure to CO2 Brine 

      Chavez Panduro, Elvia Anabela; Torsæter, Malin; Gawel, Kamila; Bjørge, Ruben; Gibaud, Alain; Yang, Yi; Sørensen, Henning; Frykman, Peter; Kjøller, Claus; Breiby, Dag Werner (Journal article; Peer reviewed, 2017)
      Long-lasting cement plugging of wells is crucial for successful CO2 storage in underground reservoirs. It requires a profoundly improved understanding of the behavior of fractured cement under realistic subsurface conditions ...
    • Computed X-ray Tomography Study of Carbonate Precipitation in Large Portland Cement Pores 

      Chavez Panduro, Elvia Anabela; Torsæter, Malin; Gawel, Kamila; Bjørge, Ruben; Gibaud, Alain; Bonnin, Anne; Schlepütz, Christian M.; Breiby, Dag Werner (Journal article; Peer reviewed, 2019)
      Cement degradation caused by CO2 exposure is an increasingly important environmental challenge that must be understood, for example, if former oil reservoirs are to be used for CO2 storage. When exposed to CO2-saturated ...
    • Cu atoms suppress misfit dislocations at the β″/Al interface in Al-Mg-Si alloys 

      Saito, Takeshi; Ehlers, Flemming J H; Lefebvre, Williams; Hernandez-Maldonado, David; Bjørge, Ruben; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Mørtsell, Eva Anne; Holmestad, Randi (Journal article, 2016)
      The Cu interactions with the Al–Mg–Si alloy main hardening phase β″ are investigated in atomic scale, by using experimental and simulated high angle annular dark-field scanning transmission electron microscopy techniques ...
    • 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 ...
    • Effects of Water Content and Temperature on Bulk Resistivity of Hybrid Cement/Carbon Nanofiber Composites 

      Gawel, Kamila; Taghipour, Ali; Bjørge, Ruben; Wenner, Sigurd; Gawel, Bartlomiej; Ghaderi, Amir; Cerasi, Pierre (Peer reviewed; Journal article, 2020)
      Cement nanocomposites with carbon nanofibers (CNFs) are electrically conductive and sensitive to mechanical loads. These features make them useful for sensing applications. The conductive and load sensing properties are ...
    • Formation of incoherent deformation twin boundaries in a coarse-grained Al-7Mg alloy 

      Jin, Shenbao; Zhang, Kai; Bjørge, Ruben; Tao, NR; Marthinsen, Knut; Lu, K; Li, Yanjun (Journal article; Peer reviewed, 2015)
      Deformation twinning has rarely been observed in coarse grained Al and its alloys except under some extreme conditions such as ultrahigh deformation strain or strain rates. Here, we report that a significant amount of Σ3 ...
    • HAADF-STEM and DFT investigations of the Zn-containing β'' phase in Al-Mg-Si alloys 

      Saito, Takeshi; Ehlers, Flemming J H; Lefebvre, Williams; Hernandez-Maldonado, D; Bjørge, Ruben; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmestad, Randi (Journal article, 2014)
      The Zn-containing β″ phase in Al–Mg–Si alloys was investigated by aberration corrected high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), combined with density functional theory (DFT) ...
    • Multislice image simulations of sheared needle‐like precipitates in an Al‐Mg‐Si alloy 

      Christiansen, Emil; Ringdalen, Inga Gudem; Bjørge, Ruben; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2020)
      The image contrast of sheared needle‐like urn:x-wiley:00222720:media:jmi12901:jmi12901-math-0001 precipitates in the Al‐Mg‐Si alloy system is investigated with respect to shear‐plane positions, the number of shear‐planes, ...
    • Quantifying the grain boundary segregation strengthening induced by post-ECAP aging in an Al-5Cu alloy 

      Jia, Hailong; Bjørge, Ruben; Cao, Lingfei; Hui, Song; Marthinsen, Knut; Li, Yanjun (Journal article, 2018)
      Hardening on annealing (HOA) has been frequently observed in nanostructured metals and alloys. For nanostructured materials obtained by severe plastic deformation (SPD), HOA has been attributed to the reduction of dislocation ...
    • Scanning transmission electron microscopy studies of precipitation in Al-Mg-Ge alloys 

      Bjørge, Ruben (Doktoravhandlinger ved NTNU, 1503-8181; 2011:234, Doctoral thesis, 2011)
      Precipitation in three Al-Mg-Ge(-Si-Cu) alloys has been investigated using transmission electron microscopy. The alloy compositions were chosen to be similar to previously studied Al-Mg-Si(-Cu) alloys to facilitate direct ...
    • Soft particles assisted grain refinement and strengthening of an Al-Bi-Zn alloy subjected to ECAP 

      Jia, Hailong; Bjørge, Ruben; Marthinsen, Knut; Mathiesen, Ragnvald; Li, Yanjun (Journal article; Peer reviewed, 2017)
      With the aim to improve the strength of potential Pb-free Al-Bi based bearing alloys, an Al-6Bi-8Zn alloy was subjected to equal channel angular pressing (ECAP). To reveal the roles played by the soft Bi particles, an ...
    • The deformation and work hardening behaviour of a SPD processed Al-5Cu alloy 

      Jia, Hailong; Bjørge, Ruben; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2017)
      An Al-5wt.%Cu alloy supersaturated with Cu in solid solution was subjected to equal channel angular pressing (ECAP). The microstructuralevolution was systematically investigated by backscattered electron (BSE)imaging, ...
    • The deformation and work hardening behaviour of a SPD processed Al-5Cu alloy 

      Jia, Hailong; Bjørge, Ruben; Marthinsen, Knut; Li, Yanjun (Journal article; Peer reviewed, 2017)
      An Al-5 wt.% Cu alloy supersaturated with Cu in solid solution was subjected to equal channel angular pressing (ECAP). The microstructural evolution was systematically investigated by backscattered electron (BSE) imaging, ...