### “On the Use of Constitutive Internal Variable Equations for Thermal Stress Predictions in Aluminium Casting”

**Authors:**Asbjørn Mo and Erik J. Holm,

**Affiliation:**Institute for Energy Technology (IFE)

**Reference:**1993, Vol 14, No 1, pp. 43-58.

**Keywords:**Internal variables, constitutive equations, thermal stresses, aluminium casting

**Abstract:**The report discusses the use of constitutive equations with internal variables in mathematical calculations of the thermally induced strains and stresses that arise during casting of aluminium. Application of the so-called MATMOD (MATerials MODel) constitutive relations for the viscoplastic deformation of the material is first discussed in relation to the specific characteristics of the casting process. Some numerical time integrations of the one-dimensional version of the MATMOD equations that are relevant for aluminium casting are then presented. The evolution of temperature and total strain are here chosen to be close to values experienced in the direct chill (D.C.) casting process, and values for thermally induced strains and stresses are calculated. The results are compared with predictions based on the traditional approach, in which a set of representative stress-strain curves at different constant temperatures and strain rates constitute the complete description of the viscoplastic deformation.

PDF (2290 Kb) DOI: 10.4173/mic.1993.1.3

**DOI forward links to this article:**

[1] N. Jamaly, A.B. Phillion, S.L. Cockcroft and J.-M. Drezet (2012), doi:10.1002/9781118357002.ch34 |

[2] N. Chobaut, D. Carron, S. Arsène, P. Schloth and J.-M. Drezet (2015), doi:10.1016/j.jmatprotec.2015.03.029 |

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**BibTeX:**

@article{MIC-1993-1-3,

title={{On the Use of Constitutive Internal Variable Equations for Thermal Stress Predictions in Aluminium Casting}},

author={Mo, Asbjørn and Holm, Erik J.},

journal={Modeling, Identification and Control},

volume={14},

number={1},

pages={43--58},

year={1993},

doi={10.4173/mic.1993.1.3},

publisher={Norwegian Society of Automatic Control}

};