• Assessment of yield and fracture criteria using shear and bending tests 

      Reyes, Aase Gavina Roberg; Eriksson, Magnus; Lademo, Odd-Geir; Hopperstad, Odd Sture; Langseth, Magnus (Journal article; Peer reviewed, 2009)
      This article deals with the calibration of a fracture criterion that has been implemented in a material model in LS-DYNA. The failure process in thin-walled metallic materials is complex and often due to interaction between ...
    • Casing design for geothermal wells at super critical conditions 

      Johannessen, Lars-Endre; Hals, Jostein Oddershede (Master thesis, 2018)
      In this thesis, mechanisms governing the mechanical response of casing systems in high-temperature geothermal wells have been studied. To increase the efficiency of geothermal energy production it is desirable to produce ...
    • Determination of Ductile Fracture Parameters of a Dual-Phase Steel by Optical Measurements 

      Gruben, Gaute; Vysochinskiy, Dmitry; Coudert, Térence; Reyes, Aase Gavina Roberg; Lademo, Odd-Geir (Journal article; Peer reviewed, 2013)
      Marciniak–Kuczynski and Nakajima tests of the dual-phase steel Docol 600DL (www.ssab.com/) have been carried out for a range of stress-states spanning from uniaxial tension to equi-biaxial tension. The deformation histories ...
    • Determination of forming limit strains using Marciniak-Kuczynski tests and automated digital image correlation procedures 

      Vysochinskiy, Dmitry; Coudert, Térence; Reyes, Aase Gavina Roberg; Lademo, Odd-Geir (Journal article; Peer reviewed, 2012)
      Forming limit strains are used to construct a forming limit diagram (FLD), which is a diagram in the principal strain space, traditionally used for designing forming operations of sheet metals. A line indicating the boundary ...
    • Experimental detection of forming limit strains on samples with multiple local necks 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2016)
      Sheet metal formability is traditionally described by the forming limit curve (FLC). Experimental FLCs are obtained by performing formability tests and determining failure strains. The strains are usually measured either ...
    • Experimental detection of the onset of local necking in an aluminium sheet 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2014)
      Forming limit diagrams (FLDs) are widely used to assess metal sheet formability. Experimental FLDs are obtained by performing formability tests and determining failure strains. The standard method for detection of forming ...
    • Experimental detection of the onset of local necking in an aluminium sheet 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2014)
      Forming limit diagrams (FLDs) are widely used to assess metal sheet formability. Experimental FLDs are obtained by performing formability tests and determining failure strains. The standard method for detection of forming ...
    • Experimental study on the formability of AA6016 sheets pre-strained by rolling 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2017)
      The effects of prestrain by rolling on the formability of AA6016 sheets in the biaxial stretching region are studied in this paper. An experimental program including formability experiments has been carried out for as-received ...
    • Forming limit diagrams with an FE-based approach for sheets under non-proportional loading 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Berstad, Torodd; Lademo, Odd-Geir (Chapter, 2009)
      In this study, LS-DYNA was used to predict the experimental forming limit diagrams (FLDs) for prestrained sheets in aluminum alloy Al2008-T4 found by Graf and Hosford [1]. The original data of Graf and Hosford [1] includes ...
    • Material characterization and modeling of textured aluminum alloys used in a bumper system 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Lademo, Odd-Geir; Langseth, Magnus (Chapter, 2005)
      In the present paper, two materials AA7108 and AA6060, which can be parts of a typical bumper system in aluminum, have been characterized. Material properties were identified for a material model that was recently implemented ...
    • Modeling of textured aluminum alloys used in a bumper system: Material tests and characterization 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Lademo, Odd-Geir; Langseth, Magnus (Journal article; Peer reviewed, 2006)
      The three materials AA7108, AA7003 and AA6060, which can be parts of a typical bumper system in aluminum, were characterized in the present paper. Different tempers of the materials were studied. Through simple material ...
    • Prediction of necking for two aluminum alloys under non-proportional loading by using an FE-based approach 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Berstad, Torodd; Lademo, Odd-Geir (Journal article; Peer reviewed, 2008)
      Forming Limit Diagrams (FLDs) were found numerically for sheets under non-proportional loading by means of an FE-based Marciniak–Kuczynski (M-K) analysis. The material model used in the analysis includes two instability ...
    • Validation study of failure prediction in crash analysis 

      Reyes, Aase Gavina Roberg; Dørum, Cato; Hopperstad, Odd Sture; Langseth, Magnus; Lademo, Odd-Geir; Eriksson, Magnus (Chapter, 2008)
      Modeling of plastic deformation and failure is critical in crash analysis. In the present paper, we have studied one approach to represent instabilities and damage evolution in non-linear finite element analyses of forming ...