External Circular Crack Research Articles

Size of thermal plastic zones around external cracks

This paper presents a solution of the steady-state thermal stresses and displacements in an infinite solid containing an external circular crack whose surfaces are exposed to an antisymmetric temperature field. The singular stresses round the leading edge of the crack are eliminated by adopting Dugdale's hypothesis concerning the existence of a thin plastic zone at the boundary of the crack. Lengths of plastic zones for various thermal disturbances are calculated and shown in curves.

Thermal stresses in a solid weakened by an external circular crack

Linear thermoelastic problems are solved for the thermal stress and displacement fields in an elastic solid of infinite extent weakened by a plane of discontinuity or crack occupying the space outside of a circular region. The faces of the crack are heated by maintaining them at certain temperature and/or by some prescribed heat flux the distributions of which are such that their magnitudes diminish at infinity. Special emphasis is given to the case when the circular region surrounded by the external crack is insulated from heat flow. The solution to this thermal stress problem may be combined with that of applying appropriate tractions to the crack faces, thus providing the necessary ingredients for extending the Dugdale hypothesis to thermally-stressed bodies containing cracks. More specifically, the results of the analysis permit an estimate of the plastic zone size and the plastic energy dissipation for an external circular crack. Information of this kind contributes to the understanding of the mechanics of fracture initiation in ductile materials.

Elastic equilibrium of an infinite body weakened by an external circular crack

Elastic equilibrium of an infinite body weakened by an external circular crack