Fe-based high-entropy alloy with excellent mechanical properties enabled by nanosized precipitates and heterogeneous grain distribution  

作　　者：Heechan Jung Sangwon Lee Taehyeok Kang Alireza Zargaran Pyuck-Pa Choi Seok Su Sohn 

机构地区：[1]Department of Materials Science and Engineering,Korea University,Seoul 02841,Republic of Korea [2]Department of Materials Science and Engineering,Korea Advanced Institute of Science and Technology,Daejeon 34141,Republic of Korea [3]Graduate Institute of Ferrous and Energy Materials Technology,Pohang University of Science and Technology,Pohang 37673,Republic of Korea

出　　处：《Journal of Materials Science & Technology》2024年第14期71-81,共11页材料科学技术（英文版）

基　　金：supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(Nos.NRF-2022R1A5A1030054,NRF-2023M3H4A6A01058096).

摘　　要：High-entropy alloys(HEAs)consisting of CoCrFeNiAlTi systems,with a face-centered cubic(FCC)matrix reinforced by ordered L12 precipitates,have demonstrated exceptional strength-ductility combinations.However,the current compositional design of HEAs heavily relies on high Ni and Co contents,compro-mising the balance between properties and cost.Thus,it is crucial to optimize the cost-performance trade-offby fine-tuning the range of Fe,Co,and Ni,while maintaining excellent strength-ductility com-bination.In this study,we propose a novel Fe-based HEA with nanosized precipitates and a heteroge-neous grain distribution,achieving a strength-ductility combination comparable to state-of-the-art Ni-or Co-based HEAs.The alloy benefits from both precipitation hardening and hetero-deformation-induced strengthening attributed to the heterogeneous grain distribution,resulting in excellent yield strength of 1433 MPa,tensile strength of 1599 MPa,and ductility of 22%.The microstructural evolution and its in-fluence on mechanical properties are unraveled with respect to the observation of precipitate-dislocation interaction and hetero-deformation-induced stress(HDI stress)evaluation.This study suggests that the challenge of balancing properties and cost can be addressed through optimized compositional and mi-crostructural design.

关 键 词：High-entropy alloys Precipitation Heterogeneous microstructure Mechanical property HDI stress 

分 类 号：TG139[一般工业技术—材料科学与工程]