Fine-scale structure of dislocations and debris in deformed Ni-based superalloy R104

The role of fine-scale defects in a polycrystalline superalloy has been investigated. Cube-slip, a critical component of the dominant deformation mode of wavy slip, appears to play a key role in the overall deformation process, along with repeated cross-slip. Within regions which deform by wavy slip, fine-scale defect structures are observed, and are the main focus of the present work. The size scale of these features necessitates that high-resolution scanning transmission electron microscopy be employed, in addition to diffraction contrast methods. Stacking fault tetrahedra appear with great frequency, and their role in the alloy's behavior at two different temperatures is also discussed.