UNUSUAL STRESS SERRATIONS AND PLC BANDS IN HIGH MANGANESE AUSTENITIC FE-MN-C TWIP STEEL [Poster #17]

Deformation twinning and dynamic strain aging (DSA) are two major phenomena occurring in Fe-Mn-C twinning-induced plasticity (TWIP) steels. DSA is manifested with serrated plastic flow, with stress serrations appearing on stress-strain or stress-time curves. TWIP steels, especially Fe-Mn-C TWIP steels, show apparent serrated plastic flow. However, the stress serrations and associated Portevin-Le Chatelier (PLC) band behavior of such steels reported in several publications, especially at very low strain rates, are not consistent. This paper is to investigate the serrated plastic flow and the spatio-temporal behaviors of PLC bands in a Fe-Mn-C TWIP steel at very low strain rates, by means of in-situ tensile tests, in conjunction of digital image correlation (DIC) technique.
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