Stress Intensity Factor for a Semi-infinite Crack Heated by a Moving Source of Heat

Abstract

The steady-state temperature and thermal stress fields have been calculated in the case that the heat source moves with constant velocity along a line in an infinite plane. Stresses were evaluated in two ways: one method is based on the superposition of body forces corresponding to the thermal strains and the other, superposition of axi-symmetric stress fields caused by an instantaneous heat source. When a semi-infinite crack follows the heat source in the plane, thermal stresses show singularities at the crack tip. The estimated mode I stress intensity is strongly affected by a heat dissipation rate to surroundings, moving velocity, heating rate, and a distance between a heat source and a crack tip. This model gives a stable crack configuration and hence will provide appropriate conditions for cleavage-cutting of brittle materials, which uses no machining bits.