TY - JOUR
T1 - Dynamic Strain Aging and Serration Behavior of Three High-Manganese Austenitic Steels
AU - Lee, Seung Yong
AU - Hwang, Byoungchul
N1 - Publisher Copyright:
© 2019, The Minerals, Metals & Materials Society and ASM International.
PY - 2019/4/15
Y1 - 2019/4/15
N2 - The strain-rate dependence of the flow stress of three high-manganese austenitic steels with different compositions was studied in terms of dynamic strain aging and serration behavior at room temperature under quasi-static strain-rate ranges from 10 −4 to 10 −1 s −1 . Tensile stress–strain curves showed that serrated flow occasionally appeared and the strain-rate dependence of flow stress was measured to be negative at all strains for Fe-22Mn-0.3C and Fe-30Mn-0.2C steels and at higher strain for Fe-30Mn-0.2C-1.5Al steel. Based on the tendency for a critical strain corresponding to the onset strain of serrated flow and electron back-scattered diffraction analysis, it was found that serrated flow was not induced by deformation twinning and γ→ ε martensitic transformation, but by dynamic strain aging associated with the interaction between partial dislocation and solute carbon. Also, the addition of Al content increased the critical strain, meaning that it effectively prohibits dynamic strain aging. In addition, dynamic strain aging promoted deformation twinning and/or γ→ ε martensitic transformation and resulted in negative strain-rate dependence of flow stress in the high-manganese austenitic steels.
AB - The strain-rate dependence of the flow stress of three high-manganese austenitic steels with different compositions was studied in terms of dynamic strain aging and serration behavior at room temperature under quasi-static strain-rate ranges from 10 −4 to 10 −1 s −1 . Tensile stress–strain curves showed that serrated flow occasionally appeared and the strain-rate dependence of flow stress was measured to be negative at all strains for Fe-22Mn-0.3C and Fe-30Mn-0.2C steels and at higher strain for Fe-30Mn-0.2C-1.5Al steel. Based on the tendency for a critical strain corresponding to the onset strain of serrated flow and electron back-scattered diffraction analysis, it was found that serrated flow was not induced by deformation twinning and γ→ ε martensitic transformation, but by dynamic strain aging associated with the interaction between partial dislocation and solute carbon. Also, the addition of Al content increased the critical strain, meaning that it effectively prohibits dynamic strain aging. In addition, dynamic strain aging promoted deformation twinning and/or γ→ ε martensitic transformation and resulted in negative strain-rate dependence of flow stress in the high-manganese austenitic steels.
UR - http://www.scopus.com/inward/record.url?scp=85061183839&partnerID=8YFLogxK
U2 - 10.1007/s11661-019-05134-y
DO - 10.1007/s11661-019-05134-y
M3 - Article
AN - SCOPUS:85061183839
SN - 1073-5623
VL - 50
SP - 1693
EP - 1700
JO - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
JF - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
IS - 4
ER -