High-/medium-entropy alloys(H/MEAs)of face-centered-cubic-structured single phase usually suffer from a glaring drawback of low yield strength.Even worse,the trade-off emerges frustratingly between strength and ductility as strength increases.Here,the lamellar heterostructure(HS)is designed in an equiatomic ternary CoNiFe MEA by means of cold rolling followed by an incomplete recrystallization annealing.The lamellar HS consists of the soft recrystallized grains as well as severely deformed structures which are partly reserved.By com-parison to the coarse-grained counterpart,the lamellar HS,shows a well enhanced yield strength-ductility synergy,together with an increased yield strength.This is ascribed to the hetero-deformation-induced(HDI)stress in HS during tensile deformation.Accordingly,the HDI strain hardening is induced,serving as an important addition to the conventional forest hardening.The HDI hardening is evidenced experimentally to account for a large proportion of global strain hardening.Furthermore,a fully recrystallized microstructure is obtained to show a simul-taneous increase in both yield strength and ductility.The microstructures are evaluated in detail prior to and after tensile deformation by using the electron backscattered diffraction and transmission electron microscope observa-tions.The mechanism for HDI strain hardening in various microstructures is analyzed to correlate to the evolution of microstructures in terms of the kernel average misorienta-tion values,Schmid factor,and dislocation behaviors in response to plastic deformation.

Xin-Xin Ding;Jing Wang;Dong Liu;Chang Wang;Ping Jiang;Hua Qu;Guang-Hua Liu;Fu-Ping Yuan;Xiao-Lei Wu

School of Physical Science and Technology,Tiangong University,Tianjin 300387,China;State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Science,Beijing 100190,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China;Special Steel Department,Central Iron and Steel Research Institute,Beijing 100081,China

稀有金属（英文版）

[1]Xin-Xin Ding;Jing Wang;Dong Liu;Chang Wang;Ping Jiang;Hua Qu;Guang-Hua Liu;Fu-Ping Yuan;Xiao-Lei Wu-.Heterostructuring an equiatomic CoNiFe medium-entropy alloy for enhanced yield strength and ductility synergy)[J].稀有金属（英文版）,2022(08):2894-2905

Heterostructuring,CoNiFe,glaring,frustratingly,misorienta

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