Achieving a High-Strength CoCrFeNiCu High-Entropy Alloy with an Ultrafine-Grained Structure via Friction Stir Processing

作     者：Ning Li Cun-Lei Jia Zhi-Wei Wang Li-Hui Wu Ding-Rui Ni Zheng-Kun Li Hua-Meng Fu Peng Xue Bo-Lv Xiao Zong-Yi Ma Yi Shao Yun-Long Chang Ning Li;Cun-Lei Jia;Zhi-Wei Wang;Li-Hui Wu;Ding-Rui Ni;Zheng-Kun Li;Hua-Meng Fu;Peng Xue;Bo-Lv Xiao;Zong-Yi Ma;Yi Shao;Yun-Long Chang

作者机构：School of Material Science and EngineeringShenyang University of TechnologyShenyang 110870China Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2020年第33卷第7期

页      面：947-956页

核心收录：

学科分类：0817[工学-化学工程与技术] 0806[工学-冶金工程] 08[工学] 0807[工学-动力工程及工程热物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0802[工学-机械工程] 0703[理学-化学] 0811[工学-控制科学与工程] 

基　　金：supported by the National Natural Science Foundation of China under Grant Nos. 51601194, 51975553, 51575362 the IMR SYNL-T.S. Kê Research Fellowship 

主　　题：grain microstructure deformation 

摘      要：High-entropy alloys(HEAs) are a new class of materials with a potential engineering application,but how to obtain ultrafine or nano-sized crystal structures of HEAs has been a ***,we first presented an equiatomic CoCrFeNiCu HEA with excellent mechanical properties obtained via friction stir processing(FSP).After FSP,the Cu element segregation in the cast CoCrFeNiCu HEA was almost eliminated,and the cast coarse two-phase structure(several micrometers) was changed into an ultrafine-grained single-phase structure(150 nm) with a large fraction of high-angle grain boundaries and nanoscale deformation *** unique microstructure was mainly attributed to the severe plastic deformation during FSP,and the sluggish diffusion effect in dynamics and the lattice distortion effect in crystallography for ***,FSP largely improved the hardness and yield strength of the CoCrFeNiCu HEA with a value of 380 HV and more than 1150 MPa,respectively,which were 1.5 times higher than those of the base *** great strengthening after FSP was mainly attributed to the significant grain refinement with large lattice distortion and *** study provides a new method to largely refine the microstructure and improve the strength of cast CoCrFeNiCu HEAs.