| Dynamic recrystallization behavior of two austenitic stainless steels, STS 310 and STS 304, with different stacking fault energy (SFE) was studied by performing high-temperature compression tests at 800∼1100℃ with strain rates of 10¹∼10^(-3)/sec. Both austenitic stainless steels with different SFE showed similar flow stress vs. strain behavior during the compression tests. However, their microstructural evolution nature with strain increase was found to be quite different. For STS 310 specimens having high SFE, dynamic recrystallization (DRX) takes place preferentially at/or near primary grain boundaries. The specimens experienced micro band (MB) and subgrain formation prior to the recrystallization. On the other hand, in the case of the STS 304 specimens with low SFE, less MBs formed and DRX occurred rather evenly through the whole area of primary austenite grains. These microstructural differences were discussed by relating dislocation movement with SFE magnitude. The mechanisms of DRX including the evolution of subgrain boundaries to high angle ones are also discussed. |
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