The evolution of misorientation accompanying branching and growth of dendrite stems advancing into an increasingly undercooled liquid at a geometrical discontinuity in cross section (platform of a turbine blade) during solidification of a Ni-base superalloy was experimentally investigated. The misorientation generated was cumulative in nature with a systematic rotation of the principal <001>-crystal axes. It was proposed that the misorientation arose from plastic deformation of the dendrite stems during growth. Low angle boundaries were subsequently produced across impinging dendrite fronts.

Formation of Low-Angle Boundaries in Ni-Based Superalloys. N.D’Souza, M.Newell, K.Devendra, P.A.Jennings, M.G.Ardakani, B.A.Shollock: Materials Science and Engineering A, 2005, 413-414, 567-70