TY - JOUR
T1 - Effects of transformation-induced plasticity (TRIP) on tensile property improvement of Fe45Co30Cr10V10Ni5-xMnx high-entropy alloys
AU - Yang, Junha
AU - Jo, Yong Hee
AU - Kim, Dae Woong
AU - Choi, Won Mi
AU - Kim, Hyoung Seop
AU - Lee, Byeong Joo
AU - Sohn, Seok Su
AU - Lee, Sunghak
N1 - Funding Information:
This work was supported by the Korea University Grant for the seventh author, by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF- 2019R1F1A1057687 ), by Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by Ministry of Science and ICT (NRF- 2016M3D1A1023383 ), by the Brain Korea 21 PLUS Project for Center for Creative Industrial Materials, and by Korea Institute for Advancement of Technology (KIAT) grant funded by the Korea government (MOTIE) ( P0002019, The Competency Development Program for Industry Specialist). Appendix A
Funding Information:
This work was supported by the Korea University Grant for the seventh author, by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2019R1F1A1057687), by Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by Ministry of Science and ICT (NRF-2016M3D1A1023383), by the Brain Korea 21 PLUS Project for Center for Creative Industrial Materials, and by Korea Institute for Advancement of Technology (KIAT) grant funded by the Korea government (MOTIE) (P0002019, The Competency Development Program for Industry Specialist).
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2020/1/20
Y1 - 2020/1/20
N2 - A new metastable high-entropy alloy (HEA) system was suggested by thermodynamic calculations based on the Gibbs free energies of FCC and HCP and the associated stacking fault energy (SFE). The Fe45Co30Cr10V10Ni5-xMnx (x = 0, 2.5, and 5 at.%) alloys were fabricated, and their tensile properties were evaluated at room and cryogenic temperatures. The relationship between the deformation mechanism and strain hardening behavior was investigated to reveal the role of deformation-induced martensitic transformation on tensile properties. The difference in Gibbs energy decreases with increasing Mn content, leading to the decreased SFE in sequence. At room temperature, ~60% of BCC martensite in the 5Mn HEA contributes effectively to the steady strain hardening, suppressing the plastic instability. This TRIP effect achieves much eminence in the cryogenic deformation, enabling the tensile strength to reach over 1.6 GPa due to 100% of BCC and HCP martensite. In addition to the fraction of martensite, the increased Mn content reduces a critical strain required to trigger the martensitic transformation and then raises the transformation rate. The present findings may provide a guide for the design of metastable HEAs to enhance tensile properties for cryogenic applications through adjusting SFE and TRIP effect.
AB - A new metastable high-entropy alloy (HEA) system was suggested by thermodynamic calculations based on the Gibbs free energies of FCC and HCP and the associated stacking fault energy (SFE). The Fe45Co30Cr10V10Ni5-xMnx (x = 0, 2.5, and 5 at.%) alloys were fabricated, and their tensile properties were evaluated at room and cryogenic temperatures. The relationship between the deformation mechanism and strain hardening behavior was investigated to reveal the role of deformation-induced martensitic transformation on tensile properties. The difference in Gibbs energy decreases with increasing Mn content, leading to the decreased SFE in sequence. At room temperature, ~60% of BCC martensite in the 5Mn HEA contributes effectively to the steady strain hardening, suppressing the plastic instability. This TRIP effect achieves much eminence in the cryogenic deformation, enabling the tensile strength to reach over 1.6 GPa due to 100% of BCC and HCP martensite. In addition to the fraction of martensite, the increased Mn content reduces a critical strain required to trigger the martensitic transformation and then raises the transformation rate. The present findings may provide a guide for the design of metastable HEAs to enhance tensile properties for cryogenic applications through adjusting SFE and TRIP effect.
KW - High-entropy alloy (HEA)
KW - Stacking fault energy (SFE)
KW - Thermodynamic calculation
KW - Transformation-induced plasticity (TRIP)
UR - http://www.scopus.com/inward/record.url?scp=85076099458&partnerID=8YFLogxK
U2 - 10.1016/j.msea.2019.138809
DO - 10.1016/j.msea.2019.138809
M3 - Article
AN - SCOPUS:85076099458
SN - 0921-5093
VL - 772
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
M1 - 138809
ER -