Effect of notch orientation on the evolution of plasticity in superalloy single crystals

The effect of notch orientation on the evolution of slip bands in double-notched tensile samples of a single crystal superalloy loaded in a 〈0 0 1〉 orientation was experimentally investigated and compared to the results of a three-dimensional linear elastic anisotropic finite element analysis (FEA). The analysis was conducted for two orientations with notches parallel to a 〈0 1 0〉 and a 〈1 1 0〉 orientation, respectively. The observed slip traces agreed well with the predicted dominant slip systems based on the FEA. The experimental results suggest that the dominant slip planes activated at low load levels persist at higher load levels and the activation of other slip bands within a domain is initially inhibited.