A three-dimensional finite element method was used to calculate the stress intensity factors for corner cracked specimens
of a single crystal nickel-based superalloy. The anisotropic material properties and inclinations of the cracks were
shown to have significant effects on the stress intensities. Then the two-dimensional resolved shear stress approach for predicting
the crack planes and crack growth directions in single crystals was extended to the three-dimensional case. Using
this approach, the fatigue crack growth behaviour in single crystal corner cracked specimens could be explained.