An Automatic Micropolariscope Used to Study a Cracked Thread

  • T. P. Broadbent
  • H. Fessler
Conference paper


A natural, three-dimensional, slightly curved crack was found in the thread of a frozen-stress model of a screwed tubular connection. The uncracked stress field in a similarly loaded cross-section was analysed using Frocht’s shear difference method. From slices containing the crack, the load transmitted locally, the extent of the region where linear elastic fracture mechanics should apply and non-dimensional stress intensity factors kII, kI, and f(rc o) were determined. Large variations in kII kI and f(rc o) were found in this non-uniform stress field.


Crack Front Linear Elastic Fracture Mechanic Fringe Order Linear Fracture Mechanic Thread Profile 
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Copyright information

© Springer-Verlag Tokyo 1986

Authors and Affiliations

  • T. P. Broadbent
    • 1
  • H. Fessler
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of NottinghamNottinghamUK

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