The Establishment Of Thermoplastic Resin Material Constitutive Model And The Subroutine Development Based On ABAQUS

Composite material is widely used in aerospace and other high-tech areas for itslight weight, high strength and so on. the development of composite materials on thebase material has put forward higher requirements, polycarbonate which as excellentperformance of thermoplastic resin material is good for the composite base material,however, there will be some new issues in cutting process because of the enhancementof matrix effects. At the same time, polycarbonate also has a vast market andforeground as engineering plastics, and the requirements are also getting higher andhigher in the hot processing along with its expansion in use. The need of manpower andmaterial resources is relatively large in determining the materials processing parametersusing the experiment simply, which need the aid of finite element simulation to study.ABAQUS is widely used for its powerful functions, however, it does not contain aconstitutive model which suits to the nonlinear viscoelastic of thermoplastic resinmaterial, so we need to carry on the second development according to needs, at thesame time, write user subroutine according to the requirements of the constitutiveequation.This paper explains polycarbonate constitutive modeling principle and basisthrough the analysis of alpha change and beta change, parallelized a damping in theone-dimensional structure of constitutive model according to the material properties,improved the existed " Z-W-T "model, got the constitutive model Suitable for thethermoplastic plastics such as polycarbonate, and deduced its mathematical equations.This paper turns the one-dimensional model of mathematical equations into athree-dimensional form,and compiles the UMAT user subroutines based on Misesyield criterion and J2flow theory, in which the fully implicit backward Euler algorithmis used and calculates the stress plastic correction. It compiles Matlab program using"ant colony optimization", fits the material parameters in the constitutive equation. italso establishes the tensile and Hopkinson finite element model and call the UMATsubroutines to analyze polycarbonate, draws stress and plastic deformation underdifferent strain rate variation.This paper has tensile and Hopkinson experiments of polycarbonate materialunder different strain rate, then processes and contrasts the results,gets the changingrules at high strain rate and low strain rate yield variation, compares the experimentresults and laws got in simulation results, verifies the correctness of the constitutivemodel.