Blar i NTNU Open på forfatter "Bjørge, Ruben"

Viser treff 1-20 av 25

    • Acid treatment as a way to reduce shale rock mechanical strength and to create a material prone to the formation of permanent well barrier 

      Gawel, Kamila; Lozovyi, Maksym; Bhuiyan, Mohammad Hossain; Bjørge, Ruben; Fjær, Erling (Peer reviewed; Journal article, 2021)
      Utilization of natural shale formations for the creation of annular barriers in oil and gas wells is currently discussed as a mean of simplifying cumbersome plugging and abandonment procedures. Shales that are likely to ...

    • 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 ...

    • Detailed investigation of the shearing mechanism of β" precipitates in Al-Mg-Si alloys 

      Christiansen, Emil; Marioara, Calin Daniel; Ringdalen, Inga Gudem; Bjørge, Ruben; Holmedal, Bjørn; Hopperstad, Odd Sture; Holmestad, Randi (Peer reviewed; Journal article, 2020)
      The mechanism behind shearing of β'' precipitates in Al-Mg-Si alloys during deformation is investigated by applying advanced transmission electron microscopy (TEM) techniques and frozen phonon multislice TEM image simulations ...

    • 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 ...

    • Effect of Sigma Phase in Wire Arc Additive Manufacturing of Superduplex Stainless Steel 

      Akselsen, Odd Magne; Bjørge, Ruben; Ånes, Håkon Wiik; Ren, Xiaobo; Nyhus, Bård (Peer reviewed; Journal article, 2021)
      In the present study, the thermal program in wire and arc additive manufacturing has been varied in terms of heat input and interpass temperature. Three walls were completed with subsequent Charpy V impact toughness and ...

    • 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 ...

    • Electrical and thermal stability of Al-Cu welds: Performance benchmarking of the hybrid metal extrusion and bonding process 

      Elkjær, Aksel Sean; Sørhaug, Jørgen A; Ringen, Geir; Bjørge, Ruben; Grong, Øystein (Peer reviewed; Journal article, 2022)
      Advances in joining processes for aluminum and copper are sought after to facilitate the greater adoption of aluminum in electrical applications. Aluminum's chemical affinity to copper causes the joining and lifetime of ...

    • 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) ...

    • 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 ...

    • Local mechanical properties and precipitation inhomogeneity in large-grained Al–Mg–Si alloy 

      Hagen, Anette Brocks; Wenner, Sigurd; Bjørge, Ruben; Wan, Di; Marioara, Calin Daniel; Holmestad, Randi; Ringdalen, Inga Gudem (Peer reviewed; Journal article, 2022)
      Al–Mg–Si (6xxx series) alloys show excellent mechanical properties due to the precipitates formed during heat treatment. However, heat treatment of these alloys results in a soft precipitation free zone (PFZ) close to grain ...

    • The microstructural origin of a hardness double-peak in an age-hardened EN-AW 6082 

      Hell, Christoph Martin; Holmedal, Bjørn; Bjørge, Ruben; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2023)
      In this study, the origin of a double-peak during artificial aging of an EN-AW 6082 is analyzed with (S)TEM. The acquired TEM data is used as an input into a strength model by Holmedal [1] to explore the origin of the ...

    • Microstructure and Properties of Wire Arc Additive Manufacturing of Inconel 625 

      Akselsen, Odd Magne; Bjørge, Ruben; Ånes, Håkon Wiik; Ren, Xiaobo; Nyhus, Bård (Journal article; Peer reviewed, 2022)
      In the present investigation, wire arc additive manufacturing of Inconel 625 was carried out with the cold metal transfer variant of the metal inert gas process. The heat input varied between 0.46 and 0.63 kJ/mm, which is ...

    • 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, ...

    • Prominent role of multi-scale microstructural heterogeneities on superplastic deformation of a high solid solution Al–7Mg alloy 

      Zha, Min; Zhang, Hongmin; Jia, Hailong; Gao, Yipeng; Jin, Shenbao; Sha, Gang; Bjørge, Ruben; Mathiesen, Ragnvald; Roven, Hans Jørgen; Wang, Hui-Yuan; Li, Yanjun (Peer reviewed; Journal article, 2021)
      Achieving high superplasticity in single-phase Al alloys remains a challenge, since the fine-grained structure required for superplastic deformation coarsens rapidly in the absence of dispersed second-phase particles during ...