文献类型：期刊文献

英文题名：The origin of good mechanical and soft magnetic properties in a CoFeNi-based high-entropy alloy with hierarchical structure

作者：Lu, Tiwen[1,2];He, Tianbing[2];Andreoli, Angelo F.[3];Yao, Ning[1];Wan, Bingbing[4];Scudino, Sergio[2]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China;[2]Leibniz IFW Dresden, Inst Complex Mat, Helmholtz Str 20, D-01069 Dresden, Germany;[3]Univ Fed Sao Carlos, Dept Mat Engn, Rodovia Washington Luis,Km 235 SP 310, BR-13565905 Sao Carlos, SP, Brazil;[4]Dongguan Univ Technol, Sch Mat Sci & Engn, Dongguan 523808, Peoples R China

年份：2024

卷号：215

外文期刊名：MATERIALS CHARACTERIZATION

收录：;EI(收录号：20243216832059);WOS:【SCI-EXPANDED(收录号:WOS:001291198800001)】；

基金：This work was financially supported by the National Key Research and Development Project (No.2022YFB4600019) , National Natural Science Foundation of China (No.52275147, No.52205152) .

语种：英文

外文关键词：High-entropy alloys; Heterogeneous microstructure; Mechanical properties; Soft magnetic properties; Deformation behavior

摘要：With the industry development, materials that combine good mechanical properties with new functional applications are in high demand. Here, a solution was provided to overcome low mechanical properties of soft magnetic materials through heterostructure design in CoFeNi high-entropy alloys (HEA). A CoFeNi-based HEA with a hierarchical structure with heterogeneous microstructure, consisting of body-centered cubic (BCC) bands, ultra-fine grained dual-phase and non-recrystallized lamellae (NRL) zones containing a high-density of nanoprecipitates, was fabricated and finely tuned by cold rolling (CR) and annealing. The HEA annealed at 850 degrees C (HEA-850) exhibits a noteworthy strength-ductility synergy than the counterparts with homogeneous dual-phase microstructures. The yield strength and elongation of the HEA-850 sample are nearly up to 1 GPa and 24%, respectively. Furthermore, because of the elimination of high-density dislocations, this alloy possesses good soft magnetic characteristics, and the saturation magnetization (Ms) and coercivity are 120 emu/g and 455 A/m, respectively. Detailed microstructure observations reveal that the high yield strength is mainly attributed to the interphase boundary strengthening from the dual-phase ultra-fine regions and nanoprecipitate strengthening as well as dislocation strengthening from NRL regions. Due to the mechanical and microstructural heterogeneity, multiple hetero-deformation induced hardening sustains persistent work hardening during tensile deformation, resulting in the reasonable ductility in the HEA-850 sample. The novel provides an important insight into developing high-performance materials with a superior combination of mechanical and functional properties using heterogeneous microstructure.