TY - JOUR
T1 - A quasi in-situ study on the deformation mechanism in a 2.2Cr heat resistant steel
AU - Cheng, L.
AU - Chen, Y. L.
AU - Gu, X. F.
AU - Yu, W.
AU - Cai, Q. W.
AU - Suzuki, K.
AU - Miura, H.
AU - Misra, R. D.K.
N1 - Funding Information:
The authors at USTB are grateful for the financial support from National Natural Science Foundation of China (No. 51274036 ) and the China Postdoctoral Science Foundation (No. 2019TQ0028 ). The authors at USTB are grateful to Professor R.D.K. Misra for his willingness to collaborate in the study described here and for meaningful discussion. We are grateful to Dr. Jingxuan Liu for stimulating discussion.
Publisher Copyright:
© 2020 Elsevier B.V.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/6/24
Y1 - 2020/6/24
N2 - We elucidate here the micromechanism of deformation at elevated temperatures in a newly designed 2.2Cr–bainitic high strength and heat resistant steel using a quasi in–situ approach, which enabled us to describe the evolution of microstructure and corresponding mechanisms concerning plastic deformation at elevated temperatures. A new mechanism referred as dynamic precipitation (M7C3)−assisted continuous dynamic recrystallization process is proposed that illustrates the underlying reason for the ultrahigh strength (>400 MPa at 650 °C) of newly designed heat resistant steel. The study revealed the interactions between grain boundary sliding, dynamic recrystallization and shearing process, and the critical stress required for transition to corresponding deformation mechanisms are discussed quantitatively. It is proposed that the newly defined mechanism can enhance strain–hardening ability at high temperature, which is mainly attributed to dynamic precipitation at triple junctions of (sub)-grain boundaries. The study provides a new pathway to stretch the limits of high–temperature strength of heat–resistant steels.
AB - We elucidate here the micromechanism of deformation at elevated temperatures in a newly designed 2.2Cr–bainitic high strength and heat resistant steel using a quasi in–situ approach, which enabled us to describe the evolution of microstructure and corresponding mechanisms concerning plastic deformation at elevated temperatures. A new mechanism referred as dynamic precipitation (M7C3)−assisted continuous dynamic recrystallization process is proposed that illustrates the underlying reason for the ultrahigh strength (>400 MPa at 650 °C) of newly designed heat resistant steel. The study revealed the interactions between grain boundary sliding, dynamic recrystallization and shearing process, and the critical stress required for transition to corresponding deformation mechanisms are discussed quantitatively. It is proposed that the newly defined mechanism can enhance strain–hardening ability at high temperature, which is mainly attributed to dynamic precipitation at triple junctions of (sub)-grain boundaries. The study provides a new pathway to stretch the limits of high–temperature strength of heat–resistant steels.
KW - Deformation mechanism
KW - Dynamic recrystallization
KW - Grain boundary sliding
KW - Precipitation
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U2 - 10.1016/j.msea.2020.139557
DO - 10.1016/j.msea.2020.139557
M3 - Article
AN - SCOPUS:85085272161
VL - 788
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
SN - 0921-5093
M1 - 139557
ER -