The role of deformation temperature and strain on grain boundary engineering of Inconel 600

The present study investigates the effect of deformation temperature and strain on the formation of twin boundaries in Inconel 600. With a constant strain rate of 0.003/s, deformation temperatures were varied between 25 degrees C and 982 degrees C while strains varied between 11% and 80%. The resulting microstructures were characterized using electron back scatter diffraction both immediately following deformation and after an annealing cycle at 1025 degrees C. Comparison of the grain boundary characters associated with the samples enabled correlation of the processing parameters to the formation of desirable coherent twin boundaries and the identification of a deformation mechanism map. Processing parameters associated with strain annealing and dynamic recovery were found to promote the formation and retention of twin boundaries, while statically and dynamically recrystallized microstructures tend to contain large proportions of random grain boundaries that mitigate the effects of grain boundary engineering. (C) 2014 Elsevier B.V. All rights reserved.