TY - JOUR
T1 - Dynamic strain aging and twin formation during warm deformation of a novel medium-entropy lightweight steel
AU - Khani, Rezvan
AU - Zarei-Hanzaki, A.
AU - Moshiri, A.
AU - Abedi, H. R.
AU - Sohn, Seok Su
N1 - Funding Information:
This work was supported by Korea Institute for Advancement of Technology (KIAT) grant funded by the Korea Government (MOTIE) (P0002019, Human Resource Development Program for Industrial Innovation).
Publisher Copyright:
© 2022 The Author(s)
PY - 2022/3/1
Y1 - 2022/3/1
N2 - The present study deals with the extraordinary twin formation during compressive deformation of a Fe-37.55Mn-8.5Al-0.6C (wt.%) low-density steel at warm temperature regime (200–600 °C). Despite the conventional opinion regarding the restrictive effect of increasing temperature on the occurrence of deformation twinning, not only the twin boundary fraction did not decrease, but also twinning was encouraged at 400 °C and even 600 °C. This was discussed relying on the occurrence of dynamic strain aging phenomenon, which caused a bump in corresponding hardening rate curves. The medium entropy of the alloy, which made short-range diffusion of solute atoms feasible and facilitated local pinning of the mobile dislocations, provided a proper condition for the occurrence of high temperature strain ageing. Finally, the unbalanced pinning of trailing and leading dislocations influenced on their velocity and caused widening the stacking faults which in-turn could significantly assist deformation twinning at such high deformation temperatures.
AB - The present study deals with the extraordinary twin formation during compressive deformation of a Fe-37.55Mn-8.5Al-0.6C (wt.%) low-density steel at warm temperature regime (200–600 °C). Despite the conventional opinion regarding the restrictive effect of increasing temperature on the occurrence of deformation twinning, not only the twin boundary fraction did not decrease, but also twinning was encouraged at 400 °C and even 600 °C. This was discussed relying on the occurrence of dynamic strain aging phenomenon, which caused a bump in corresponding hardening rate curves. The medium entropy of the alloy, which made short-range diffusion of solute atoms feasible and facilitated local pinning of the mobile dislocations, provided a proper condition for the occurrence of high temperature strain ageing. Finally, the unbalanced pinning of trailing and leading dislocations influenced on their velocity and caused widening the stacking faults which in-turn could significantly assist deformation twinning at such high deformation temperatures.
KW - Deformation twinning
KW - Dynamic strain aging
KW - Lightweight steel
KW - Mechanical properties
KW - Medium-entropy alloy
KW - Thermomechanical processing
UR - http://www.scopus.com/inward/record.url?scp=85124088836&partnerID=8YFLogxK
U2 - 10.1016/j.jmrt.2022.01.057
DO - 10.1016/j.jmrt.2022.01.057
M3 - Article
AN - SCOPUS:85124088836
SN - 2238-7854
VL - 17
SP - 1628
EP - 1641
JO - Journal of Materials Research and Technology
JF - Journal of Materials Research and Technology
ER -