Abstract
The CoCrFeMnNi high-entropy alloys(HEAs)with a(face-centered cubic)FCC structure has garnered considerable attention for its exceptional ductility and strain hardening ability.However,its yield strength is insufficient for structural applications.In this study,strengthening mechanisms in these HEAs were investi-gated to gain insight into the mechanical properties according to alloy powder size.Moreover,we present a novel approach to achieve both high strength and high ductility through the creation of a bimodal structure con-sisting of both coarse and fine grains via gas atomization and spark plasma sintering processes.A bimodally struc-tured HEA prepared with a mass ratio of 2:8 between coarse particles(75-106 μm)and fine particles(≤ 25 μm)yielded optimal results,with a strength of 491.95 MPa and elongation of 19.64％.This strength value represents an～41％increase compared with the sample that dis-played a fine single microstructure(347.08 MPa for yield strength).The strength enhancement was attributed to the prevention of plastic deformation initiation from the fine particles during deformation.This innovative approach to the creation of HEAs with bimodal structures shows pro-mise for various applications,such as structural compo-nents that require a combination of high strength and high ductility.
基金项目
Ministry of Trade,Industry & Energy(MOTIE,Korea)(20011520)
Korea Institute of Energy Technology Evaluation and Planning(KETEP)(20217510100020)
Commercialization Promotion Agency for R&D Outcomes(COMPA)(1711175258)
维普
万方数据