TY - JOUR

T1 - Computational modeling of amorphous polymers

T2 - A Lagrangian logarithmic strain space formulation of a glass–rubber constitutive model

AU - Raza, Syed Hasan

AU - Soyarslan, Celal

AU - Bargmann, Swantje

AU - Klusemann, Benjamin

PY - 2019/2/1

Y1 - 2019/2/1

N2 - We present a reformulation of the finite strain, rate dependent inelastic glass–rubber material model suggested by Buckley and Jones (1995) and extended by Adams et al. (2000) for modeling the deformation of amorphous polymers in the Lagrangian logarithmic strain space. This not only warrants a hyperelastic characterization in the bonding part which remedies problems associated with hypoelastic approaches devising objective stress rates selected on ad hoc basis, see, e.g., Dooling et al. (2001) and Li and Buckley (2009), but also allows a transparent and naturally objective implementation analogous to the geometrically linear theory. A numerical implementation into ABAQUS is pursued where algorithms for stress update and tangent moduli computations are reported. It is shown that significant reduction in nonlinear equation system size is possible in the computation of both bonding and conformational part. The characterization tests include constant-width tension, equi-biaxial tension, and simple shear. To demonstrate the robustness of the developed framework, two hypothetical problems of extreme deformation under tensile and combined tensile and torsion loading are considered. Finally, simulation of an injection stretch-blow molding process is presented as an application problem.

AB - We present a reformulation of the finite strain, rate dependent inelastic glass–rubber material model suggested by Buckley and Jones (1995) and extended by Adams et al. (2000) for modeling the deformation of amorphous polymers in the Lagrangian logarithmic strain space. This not only warrants a hyperelastic characterization in the bonding part which remedies problems associated with hypoelastic approaches devising objective stress rates selected on ad hoc basis, see, e.g., Dooling et al. (2001) and Li and Buckley (2009), but also allows a transparent and naturally objective implementation analogous to the geometrically linear theory. A numerical implementation into ABAQUS is pursued where algorithms for stress update and tangent moduli computations are reported. It is shown that significant reduction in nonlinear equation system size is possible in the computation of both bonding and conformational part. The characterization tests include constant-width tension, equi-biaxial tension, and simple shear. To demonstrate the robustness of the developed framework, two hypothetical problems of extreme deformation under tensile and combined tensile and torsion loading are considered. Finally, simulation of an injection stretch-blow molding process is presented as an application problem.

KW - Glass–rubber constitutive model

KW - Lagrangian logarithmic strains

KW - Return mapping

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=85056699491&partnerID=8YFLogxK

U2 - 10.1016/j.cma.2018.10.007

DO - 10.1016/j.cma.2018.10.007

M3 - Journal articles

AN - SCOPUS:85056699491

VL - 344

SP - 887

EP - 909

JO - Computer Methods in Applied Mechanics and Engineering

JF - Computer Methods in Applied Mechanics and Engineering

SN - 0045-7825

ER -