The Influence of Temperature on the Strain-hardening Behavior of Fe-22/25/28Mn-3Al-3Si TRIP/TWIP Steels
Dean Pierce, Jake Benzing, Jose Jimenez, Tilmann Hickel, Ivan Bleskov, Jong Keum, Dierk Raabe, Jim Wittig
The influence of temperature and stacking fault energy (SFE) on the strain-hardening behavior and critically resolved shear stress for twinning was investigated for three Fe–22/25/28Mn–3Al–3Si wt.% transformation- and twinning-induced plasticity (TRIP/TWIP) steels. The SFEs were calculated by two different methods, density functional theory and thermodynamic model. The dislocation structure, observed at low levels of plastic deformation, transitions from "planar" to "wavy" dislocation glide with an increase in temperature, Mn content, and/or SFE. The change in dislocation glide mechanisms from planar to wavy reduces the strain hardening rate, in part due to fewer planar obstacles and greater cross slip activity. In addition, the alloys exhibit a large decrease in strength and ductility with increasing temperature from 25 °C to 200 °C, attributed to a substantial reduction in the thermally activated component of the flow stress, predominate suppression of TRIP, and a significant increase in the critically resolved shear stress for mechanical twinning.
, Benzing, J.
, Jimenez, J.
, Hickel, T.
, Bleskov, I.
, Keum, J.
, Raabe, D.
and Wittig, J.
The Influence of Temperature on the Strain-hardening Behavior of Fe-22/25/28Mn-3Al-3Si TRIP/TWIP Steels, Materialia, [online], https://doi.org/10.1016/j.mtla.2022.101425, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932520
(Accessed July 5, 2022)