A creep deformation mechanism in a polycrystalline Ni-base superalloy (Rene 88 DT) was examined using crystallographic analysis and comparison between simulated and experimental high-resolution transmission electron microscopic images. Confirmation of the magnitude of the Burgers vector of the partial dislocations involved in the creep deformation was critical in conclusively determining its nature. A new approach to determining a complex stacking fault was developed using superlattice image contrast from an experimental high-resolution transmission electron microscopic image.

Direct Observation of an Extended Complex Stacking Fault in the γ′ Phase of a Ni-Base Superalloy. P.M.Sarosi, G.B.Viswanathan, M.J.Mills: Scripta Materialia, 2006, 55[8], 727-30