Dynamic Crack Curving and Crack Branching

  • M. Ramulu
  • A. S. Kobayashi
Part of the Sagamore Army Materials Research Conference Proceedings book series (SAMC, volume 29)


The dynamic crack curving criterion proposed by Ramulu and Kobayashi1 is based on a micro-mechanic model of continuous micro- flaw growth and coalescence in the vicinity of the moving crack tip. It is a dynamic extension of the crack curving criterion proposed by Streit and Finnie.2 When an off-axis micro-flaw connects with the crack tip, the crack is momentarily kinked or bifurcated. Figure 1 shows several attempts for a rapidly propagating crack to branch in a Homalite-100 plate. Also shown is a successful crack branching under presumably a favorable state of stress.


Stress Intensity Factor Crack Velocity Dynamic Crack Dynamic Stress Intensity Factor Fracture Angle 
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Copyright information

© Plenum Press, New York 1983

Authors and Affiliations

  • M. Ramulu
    • 1
  • A. S. Kobayashi
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of WashingtonSeattleUSA

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