Hierarchical microstructure enables high strength and good ductility in as-cast Fe_(27)Ni_(35)Cr_(18.25)Al_(13.75)Co_(2)Ti_(2)Mo_(2) high-entropy alloy  

作　　者：Jiacheng Niu Zhiqiang Fu Weiping Chen Tiwen Lu Liangyan Hao Wei Xiong Haiming Wen 

机构地区：[1]Guangdong Key Laboratory for Advanced Metallic Materials Processing,South China University of Technology,Guangzhou 510640,China [2]National Engineering Research Center of Near-net-shape Forming for Metallic Materials,South China University of Technology,Guangzhou 510640,China [3]Key Laboratory of Pressure Systems and Safety,Ministry of Education,East China University of Science and Technology,Shanghai 200237,China [4]Physical Metallurgy and Materials Design Laboratory,Department of Mechanical Engineering and Materials Science,University of Pittsburgh,Pittsburgh,PA,15261,United States of America [5]Department of Materials Science and Engineering,Missouri University of Science and Technology,Rolla,Missouri 65409,United States of America

出　　处：《Journal of Materials Science & Technology》2024年第12期9-21,共13页材料科学技术（英文版）

基　　金：J.C.Niu and Z.Q.Fu acknowledge the financial support from the National Natural Science Foundation of China(No.52103360);from the Pearl River Talent Program(No.2021QN02C766);from the Basic and Applied Basic Research Foundation of Guangdong Province(No.2020A1515111104);W.P.Chen thanks the financial support from the Key-Area Research and Development Program of Guangdong Province(No.2018B090905002)。

摘　　要：As-cast alloys often require complex thermomechanical processing to obtain a hierarchical structure to achieve a good combination of strength and ductility.Here in this work,a novel hierarchical Fe_(27)Ni_(35)Cr_(18.25)Al_(13.75)Co_(2)Ti_(2)Mo_(2) high-entropy alloy(HEA)with ultra-high tensile strength and excellent ductility was fabricated by direct casting.The as-cast alloy exhibits hierarchical structure with an ul-trafine lamellar microstructure(ULM),ultrafine rhombus microstructure(URM),ultrafine vermicular mi-crostructure(UVM),nanosized precipitates and spinodal decomposition(SP)that develops during casting and cooling.The incompatibility of face-centered cubic(FCC)and body-centered cubic(BCC)phases in the deformation process leads to heterogeneous deformation-induced(HDI)hardening,which brings the alloy a tensile yield strength(YS)of~1056 MPa,an ultimate tensile strength(UTS)of~1526 MPa and a total elongation(El)of~15.6%.Additionally,the numerous interfaces generated by the hierarchical structure absorb the energy during deformation,effectively retarding the dislocation motion and causing strong work-hardening.

关 键 词：Direct casting High-entropy alloy Hierarchical microstructure Mechanical properties 

分 类 号：TG146.21[一般工业技术—材料科学与工程]