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Dynamic recrystallization (DRX) behavior in hot deformed (by uniaxial compression in a thermomechanical simulator in the temperatures range 1173 K to 1373 K [900°C to 1100°C]) Ti-modified austenitic stainless steel was studied using electron back scatter diffraction. Grain orientation spread with a ''cut off'' of 1 deg was a suitable criterion to partition dynamically recrystallized grains from the deformed matrix. The extent of DRX increased with strain and temperature, and a completely DRX microstructure with a fine grain size~4 lm (considering twins as grain boundaries) was obtained in the sample deformed to a strain of 0.8 at 1373 K (1100°C). The nucleation of new DRX grains occurred by the bulging of the parent grain boundary. The DRX grains were twinned, and a linear relationship was observed between the area fraction of DRX grains and the number fraction of R3 boundaries. The deviation from the ideal misorientation of R3 boundaries decreased with an increase in the fraction of R3 boundaries (as well as the area fraction of DRX) signifying that most R3 boundaries are newly nucleated during DRX. The generation of these R3 boundaries could account for the formation of annealing twins during DRX. The role of R3 twin boundaries on DRX is discussed.

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