Intercritical Austenite Stabilization of a Mn-Al TRIP Steel

doi:10.12068/j.issn.1005-3026.2016.02.007

Abstract

Abstract: The intercritical austenite stabilization of Fe-0.2C-7Mn-3Al steel was investigated by MMS-200 thermo-mechanical test machine in the lab. The microstructure evolution and the partitioning process of C， Mn were characterized and analyzed by using SEM， EPMA， TEM and XRD. The results show that there are always 25%-30% bulky flattened ferrite at different intercritical annealing temperatures. As the intercritical annealing temperature increases， the retained austenite content in the microstructure increases first and then decreases， with the volume fraction being 10.2%-32.5%. The retained austenite and the intercritical ferrite are located with the lath shape， and the lath width is 200-300nm. The optimized annealing temperature is 750℃. The synergistic effect of C， Mn and Al promotes the austenite stabilization during intercritical annealing， which causes the partitioning process with less time of the tested steel.

Key words: Mn-Al TRIP steel, austenite stabilization, austenite reverse transformation, microstructure evolution, retained austenite

CLC Number:

TG113.12

HU Zhi-ping， XU Yun-bo， TAN Xiao-dong. Intercritical Austenite Stabilization of a Mn-Al TRIP Steel[J]. Journal of Northeastern University Natural Science, 2016, 37(2): 179-183.

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