Dual-phase synergistic deformation characteristics and strengthening mechanism of AlCoCrFeNi_(2.1) eutectic high entropy alloy fabricated by laser powder bed fusion  

作　　者：Xu Tang Hao Zhang Zhengwang Zhu Peng Xue Lihui Wu Fengchao Liu Dingrui Ni Bolv Xiao Zongyi Ma 

机构地区：[1]Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China [2]School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China [3]Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China

出　　处：《Journal of Materials Science & Technology》2023年第19期75-85,共11页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.U21A2043);the Youth Innovation Promotion Association,CAS (No.2022191);the Bintech-IMR R&D Program (No.GYY-JSBU-2022-010).

摘　　要：Eutectic high entropy alloy(EHEA)possesses promising prospects for industrial application due to its controllable and near-equilibrium dual-phase structure.Due to the advantages of high material utiliza-tion,efficient production,and design freedom,the laser powder bed fusion(LPBF)technique provides a new path to prepare EHEA components with complex structure and excellent performance.In this study,near fully dense AlCoCrFeNi_(2.1) samples were obtained by adjusting the process parameters of LPBF.Con-sidering the balling phenomenon and powder splashing during the LPBF process,laser remelting was selected as an optimized scanning strategy to further improve the forming quality of AlCoCrFeNi21.The microstructure of remelted AlCoCrFeNi_(2.1) sample exhibited regular eutectic lamellae consisting of nano-scale face-centered-cubic(FCC)and B2 phases,in which the FCC phase accounted for a higher proportion.By investigating the tensile behavior and deformation mechanism,it was revealed that the ultrafine eu-tectic lamellae could induce a strong dual-phase synergistic strengthening,thereby significantly improv-ing the strength of the sample.Compared with the vacuum induction melted(VIM)sample,the remelted sample showed a 54%increase in ultimate tensile strength(UTS-1518 MPa)and a 130%increase in yield strength(YS-1235 MPa)with reasonable plasticity.This study indicates that by combining the design and manufacturing freedom of LPBF with the EHEA,it is expected to fabricate high-property 3D EHEA parts,expanding the application field of EHEA.

关 键 词：Laser powder bed fusion REMELTING Eutectic high entropy alloy Microstructure Deformation mechanism 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TG665[金属学及工艺—合金]