Novel (CoFe2NiV0.5Mo0.2)100-xNbx Eutectic High-Entropy Alloys with Excellent Combination of Mechanical and Corrosion Properties
来源期刊:Acta Metallurgica Sinica2020年第8期
论文作者:Ren Li Jing Ren Guo-Jia Zhang Jun-Yang He Yi-Ping Lu Tong-Min Wang Ting-Ju Li
文章页码:1046 - 1056
摘 要:The emergence of eutectic high-entropy alloys(EHEAs) offers new insights into the design of next generation structural alloys,which is due to their stable dual-phase microstructure and outstanding mechanical properties from room to elevated temperatures.In this work,a series of(CoFe2 NiV0.5Mo0.2)100-xNbx(0≤x≤12) EHEAs were designed and prepared via vacuum arc-melting.Typical eutectic microstructure composing lamellar face-centered cubic solid solution phase and C14 Laves phase appears in the as-cast EHEA when x=9.The microstructure turns to hypoeutectic or hypereutectic when x is below or beyond that critical value accordingly.The volume fraction of the hard Laves phase is proportional to the Nb addition,leading to the strength increment yet at the expense of ductility at room temperature.In particular,the EHEA having4 at% Nb shows a compressive strength of 2.1 GPa with an elongation to fracture of 45%,while EHEAs containing 9 and10 at% Nb exhibit ultrahigh yield strengths of over 1.4 GPa.The effect of Nb addition on the corrosion resistance of this Crfree EHEA system was also studied.The EHEA containing 9 at% Nb has the best anti-corrosion performance in the 3.5 wt%NaCl solution at 298±1 K,indicating a good combination of mechanical and corrosion properties.
Ren Li1,Jing Ren1,Guo-Jia Zhang1,Jun-Yang He2,Yi-Ping Lu1,Tong-Min Wang1,Ting-Ju Li1
1. Key Laboratory of Solidifi cation Control and Digital Preparation Technology (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology2. Max-Planck-Institut für Eisenforschung GmbH
摘 要:The emergence of eutectic high-entropy alloys(EHEAs) offers new insights into the design of next generation structural alloys,which is due to their stable dual-phase microstructure and outstanding mechanical properties from room to elevated temperatures.In this work,a series of(CoFe2 NiV0.5Mo0.2)100-xNbx(0≤x≤12) EHEAs were designed and prepared via vacuum arc-melting.Typical eutectic microstructure composing lamellar face-centered cubic solid solution phase and C14 Laves phase appears in the as-cast EHEA when x=9.The microstructure turns to hypoeutectic or hypereutectic when x is below or beyond that critical value accordingly.The volume fraction of the hard Laves phase is proportional to the Nb addition,leading to the strength increment yet at the expense of ductility at room temperature.In particular,the EHEA having4 at% Nb shows a compressive strength of 2.1 GPa with an elongation to fracture of 45%,while EHEAs containing 9 and10 at% Nb exhibit ultrahigh yield strengths of over 1.4 GPa.The effect of Nb addition on the corrosion resistance of this Crfree EHEA system was also studied.The EHEA containing 9 at% Nb has the best anti-corrosion performance in the 3.5 wt%NaCl solution at 298±1 K,indicating a good combination of mechanical and corrosion properties.
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