Engineering Transactions, 64, 4, pp. 563–572, 2016

Simulations of thermal softening in large strain thermoplasticity

Balbina WCISŁO
Cracow University of Technology
Poland

This paper deals with numerical simulations of the thermoplastic behaviour of isotropic materials undergoing large deformations. The attention is focused on the constitutive modelling of thermal softening understood here as a reduction of the plastic strength with increasing temperature. Different concepts of thermal softening embedded in the plasticity function are considered, in particular, the reduction of the total yield strength, its initial value or the hardening part. Moreover, apart from linear dependencies between temperature and the yield strength, the formulation involving function arc tangent is proposed. The analysed models
are numerically tested in the finite element environment AceFEM using subroutines generated with the AceGen code generator. In particular, shear banding in an elongated rectangular plate
with imperfection in plain strain conditions is investigated.
Keywords: large strains; thermoplasticity; thermal softening
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