Investigation into the growth directions of a ductile crack under tensile loading

In this paper, we use an energy variational method to study the full stress field near a stationary crack in a plane strain state in a power-law hardening material under mode I loading. Associated with the finite element method, the trajectory line fields of the principal stresses and the maximum shear stresses have been drawn in order to determine the crack growth direction. It appears that the crack can propagate along a cleavage band or along a slip band according to the triaxial tensile stress level in the vicinity of the crack. The growth direction of a ductile crack depends on the competition between the stress concentrations along these bands.