Achieving strength-ductility synergy in a non-equiatomic Cr_(10)Co_(30)Fe_(30)Ni_(30)high-entropy alloy with heterogeneous grain structures  

作　　者：Chen-Liang Chu Wei-Ping Chen Jun-Chen Liu Qiang Chen Zhi-Qiang Fu 

机构地区：[1]Guangdong Key Laboratory for Advanced Metallic Materials Processing,South China University of Technology,Guangzhou,510641,China [2]Southwest Technology and Engineering Research Institute,Chongqing,400039,China

出　　处：《Rare Metals》2022年第8期2864-2876,共13页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (No.52103360);the Basic and Applied Basic Research Foundation of GuangdongProvince (No.2020A1515111104);the Key-Area Research and Development Program of Guangdong Province (No. 2018B090905002)

摘　　要：Cold rolling and post-deformation annealing(PDA)heat treatments were used to produce heterogeneous grain structures(HGS)in a single-phase face-centered cubic(fcc)Cr_(10)Co_(30)Fe_(30)Ni_(30)high-entropy alloy(HEA).The microstructural evolution and microstructure-property relationship of the HEA were systematically studied under different states.HGS could be achieved in PDA-treated samples at 875℃for 20 s and at 900℃for 20 s(PDA-900-20 s).PDA-900-20 s sample exhibits the most excellent combination of strength and ductility,showing a tensile yield strength of~590 MPa,an ultimate strength of~706 MPa and a total elongation of~23.9%.Additionally,compared with the homogenized counterpart exhibiting homogenous grains,PDA-900-20 s sample displays a notable increment of~413%in yield strength and simultaneously maintains a good ductility.The dominated strengthening mechanisms in PDA-900-20 s sample are grain-boundary strengthening and heterogeneous deformation-induced(HDI)strengthening,whereas the good ductility is mainly resulted from the HDI ductility.Accordingly,the present study provides an effective and simple pathway to overcome the strength-ductility tradeoff of typical fcc HEAs through heterogeneous microstructure.

关 键 词：High-entropy alloy Heterogeneous grain structures Hetero-deformation-induced hardening Mechanical properties Strengthening mechanism 

分 类 号：TG139[一般工业技术—材料科学与工程]