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The recrystallization behavior of some monocrystalline superalloys was investigated both in the temperature regime of solutioning as well as at lower temperatures in the y+y' field. At very high temperatures new grains already form after a small plastic deformation of about 1 %. They only nucleate at the surface in single-phase y areas if the degree of cold work is not too high. Grain boundary motion is stopped by interdendritic y/y' areas but is barely retarded by carbides and residual eutectic islands. Even very extended recovery annealing procedures are not able to prevent recrystallization during subsequent full solutioning. For the process of cellular recrystallization in the y+y' field higher degrees of cold work are necessary. In this case a y' free zone must be absent to initiate new grains. Along the moving grain boundary the y' phase is taken into solution and reprecipitated immediately behind it. A thin recrystallized surface "jacket" leads to a higher crack density under LCF conditions but for the chosen parameters in this work the number of cycles to crack initiation is not affected.

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