TY - JOUR
T1 - Achieving superb strength in single-phase FCC alloys via maximizing volume misfit
AU - Li, Zhongtao
AU - Ma, Shihua
AU - Zhao, Shijun
AU - Zhang, Weidong
AU - Peng, Fei
AU - Li, Qian
AU - Yang, Tao
AU - Wu, Chia-Yi
AU - Wei, Daixiu
AU - Chou, Yi-Chia
AU - Liaw, Peter K.
AU - Gao, Yanfei
AU - Wu, Zhenggang
PY - 2023/3
Y1 - 2023/3
N2 - Single-phase face-centered cubic (SP-FCC) alloys normally possess low strength. Conventionally strengthening strategies inevitably cause significant ductility sacrifice. Here, a single-phase Ni-based FCC alloy with a superb yield strength of ∼1.05GPa and a good ductility of 37% is designed through maximizing the volume misfits. The misfit of the purposely targeted Ni80Mo20 alloy is severer than all existing FCC alloys, bringing the alloy a highest-ever Hall-Petch coefficient (kHP = 1034 MPa·μm1/2) and a pronounced solid solution strengthening (Δσss = 224 MPa). Current work yields two surprising and novel findings for SP-FCC alloys. First, volume misfit is a good pertinent indicator of kHP. Second, the conventional impression about the sole contribution of edge dislocations to strengthening in SP-FCC alloys may no longer hold; instead, screw dislocations can also kick in once the nonsphericity of the solute-induced stress field reaches a critical value. Altogether, this work paves a new avenue of pursuing ultimate strengthening without significant ductility sacrifice for SP-FCC alloys relying on the volume-misfit-maximization strategy.© 2023 Elsevier Ltd.
AB - Single-phase face-centered cubic (SP-FCC) alloys normally possess low strength. Conventionally strengthening strategies inevitably cause significant ductility sacrifice. Here, a single-phase Ni-based FCC alloy with a superb yield strength of ∼1.05GPa and a good ductility of 37% is designed through maximizing the volume misfits. The misfit of the purposely targeted Ni80Mo20 alloy is severer than all existing FCC alloys, bringing the alloy a highest-ever Hall-Petch coefficient (kHP = 1034 MPa·μm1/2) and a pronounced solid solution strengthening (Δσss = 224 MPa). Current work yields two surprising and novel findings for SP-FCC alloys. First, volume misfit is a good pertinent indicator of kHP. Second, the conventional impression about the sole contribution of edge dislocations to strengthening in SP-FCC alloys may no longer hold; instead, screw dislocations can also kick in once the nonsphericity of the solute-induced stress field reaches a critical value. Altogether, this work paves a new avenue of pursuing ultimate strengthening without significant ductility sacrifice for SP-FCC alloys relying on the volume-misfit-maximization strategy.© 2023 Elsevier Ltd.
KW - Single-phase face-centered cubic alloys
KW - Volume misfit
KW - Solid-solution strengthening
KW - Grain-boundary strengthening
KW - Mechanical properties
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UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-85149306330&origin=recordpage
U2 - 10.1016/j.mattod.2023.02.012
DO - 10.1016/j.mattod.2023.02.012
M3 - RGC 21 - Publication in refereed journal
SN - 1369-7021
VL - 63
SP - 108
EP - 119
JO - Materials Today
JF - Materials Today
ER -