Elucidating deformation mechanism transitions in single crystal superalloys

The deformation behaviour of single crystal Ni-based superalloys exhibits sensitivity to crystallographic orientation, strain rate and temperature. Recent studies have identified conditions under which transitions between deformation mechanisms occur, but their compositional dependency and the relation between micromechanical and bulk properties remain unexplained. This proposed experiment will perform in situ tensile deformation of three superalloys that show differing mechanical behaviour to track the resultant lattice rotation, strain partitioning, lattice misfit and stress localisation. These data will unambiguously identify the deformation transitions and, alongside TEM analysis, will elucidate the governing mechanisms.