Simultaneously enhancing the strength and ductility of Fe–Mn–C twinning-induced plasticity steel via Cr/N alloying

• Published in: Journal of materials research and technology Vol. 32; pp. 3310 - 3317
• Main Authors: shuai, Liu, Jiulong, Huang, Yinlei, Ge, Weijie, Sun, dongdong, Li, Yunli, Feng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2024; Elsevier
• Subjects: Cr/N alloying; Deformation twinning; Dynamic strain aging; Stacking fault energy; Twinning-induced plasticity steel; Stacking fault energy; Deformation twinning; Cr/N alloying; Twinning-induced plasticity steel; Dynamic strain aging
• ISSN: 2238-7854
• DOI: 10.1016/j.jmrt.2024.08.180

The effect of Cr/N alloying on the tensile deformation behavior of Fe–Mn–C twinning-induced plasticity steel was investigated through monotonic tensile tests, X-ray diffraction, electron back-scattered diffraction, transmission electron microscopy, and digital image correlation technique. The results demonstrate that the addition of Cr/N significantly enhances both the strength and ductility of Fe–18Mn-0.6C steel while dynamic strain aging (DSA) behavior weakens or even disappears. Compared with that in the Fe–18Mn-0.6C steel, more densely-spaced, thinner deformation twins were formed in the Cr/N-alloyed steel. Moreover, the Cr/N additions promote deformation twins to form over a wider strain range. This unique twinning behavior leads to a sustained high strain-hardening rate at higher strains, thereby delaying plastic instability and concurrently enhancing strength and ductility.