A modelling and simulation on failure prediction of ductile polymer based on craze evolution and annihilation

Seiichi Kobayashi, Daisuke Tomii, Kazuyuki Shizawa

Research output: Contribution to journalArticle

33 Citations (Scopus)


Ductile fracture of a polymer plate due to craze growth is characterized by a failure in the front of propagating neck. In this paper, the elastoviscoplastic constitutive equation, that explicitly represents the effect of craze, is rigorously derived. Through a thermodynamic discussion about arguments of craze rate function, a new craze evolution equation is proposed so as to express the craze concentration on the boundary between the oriented molecular region and the glassy one, and the craze annihilation in the oriented region, with a hydrostatic stress criterion of craze generation. Additionally, an evolution law of mean plastic strain affecting the craze growth is numerically identified for a polymer block with some circular holes. A finite element simulation is carried out in order to verify this model. The craze propagation and annihilation are visualized, and the possibility of failure prediction based on this model is also discussed.

Original languageEnglish
Pages (from-to)810-817
Number of pages8
JournalNippon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A
Issue number6
Publication statusPublished - 2004 Jun



  • Constitutive Equation
  • Craze
  • Damage Mechanics
  • Ductile Polymer
  • Evolution Equation
  • Finite Deformation Theory
  • Finite Element Method
  • Plasticity

ASJC Scopus subject areas

  • Mechanical Engineering

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