Modeling and Simulation of Impact Failure Characteristic of Polypropylene by Elastoviscoplastic Constitutive Law

Abstract

For simulating the final failure of glassy polymers under impact loading, Shizawa's constitutive model was modified by introducing the craze density based softening law in which the phenomenological softening law using the craze density is employed. The material parameter identification procedure in the constitutive law was developed based on the sensitivity analysis. All parameters were identified with the measurement data which were obtained by both the dumbbell-shape tensile test specimen and the notched tensile test specimen. The dart impact test was also conducted. The load displacement curve and damage zone development were compared with those obtained by the finite element analysis using proposed constitutive equations. Both results were in good agreement and the usefulness of the constitutive equations was validated.