Experimental and Simulative Investigation into the Mechanical Behaviors of Polypropylene with Craze Damage in Different Weakening Processes

摘要

This article focused on the experimental and simulative investigation into the mechanical behaviors of polypropylene (PP) at different strain rates. With the aim to describe the crazing yielding of PP, an elastoviscoplastic constitutive model with damage behavior was established and embedded into the finite element codes in the Abaqus platform. The simulation results are in good accordance with the experimental ones. Moreover, the influence of different weakening processes on the material properties was explored. In comparison to the nonweakened specimen, the weakened specimen exhibited nonlinear yielding properties under lower stress. Noteworthily, the integral strength of the weakened specimen proves to be linearly dependent on the cross-section area of the weakening zone. Eventually, the damage model of simplified dashboard was utilized to study the damage law of the dashboard with V-shaped weakening line. Results show the crack initially emerged at the weakening line and then rapidly expanded till the ends of the damage, which satisfied the damage requirements of practical dashboard. (C) 2014 Wiley Periodicals, Inc.