International Journal of Fracture

, Volume 102, Issue 4, pp 393–410 | Cite as

A comparative study of dynamic, ductile fracture initiation in two specimen configurations

  • Sumit Basu
  • R. Narasimhan
Article

Abstract

In this work a single edge notched plate (SEN(T)) subjected to a tensile stress pulse is analysed, using a 2D plane strain dynamic finite element procedure. The interaction of the notch with a pre-nucleated hole ahead of it is examined. The background material is modelled by the Gurson constitutive law and ductile failure by microvoid coalescence in the ligament connecting the notch and the hole is simulated. Both rate independent and rate dependent material behaviour is considered. The notch tip region is subjected to a range of loading rates J by varying the peak value and the rise time of the applied stress pulse. The results obtained from these simulations are compared with a three point bend (TPB) specimen subjected to impact loading analysed in an earlier work [3]. The variation of J at fracture initiation, Jc, with average loading rate J is obtained from the finite element simulations. It is found that the functional relationship between Jc and J is fairly independent of the specimen geometry and is only dependent on material behaviour.

Dynamic ductile fracture initiation finite elements microvoid coalescence specimen configuration. 

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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Sumit Basu
    • 1
  • R. Narasimhan
    • 1
  1. 1.Department of Mechanical EngineeringIndian Institute of ScienceBangaloreIndia

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