Abnormal chemical composition fluctuations in multi-principal-element alloys induced by simple cyclic deformation  

作　　者：Mengyuan He Nan Jia Xiaochun Liu Yongfeng Shen Liang Zuo 

机构地区：[1]Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education),School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China [2]Institute of Metals,College of Materials Science and Engineering,Changsha University Of Science and Technology,Changsha 410114,China

出　　处：《Journal of Materials Science & Technology》2022年第18期287-295,共9页材料科学技术（英文版）

基　　金：supported by the Natural Science Foundation of China (NSFC)(No. 51922026);the Fundamental Research Funds for the Central Universities (Nos. N2102005 and N2002005)

摘　　要：High entropy alloys exhibit excellent combination of mechanical properties because of the unique com-position fluctuations,termed as‘concentration wave’.The concentration wave was closely related to mul-tiple aspects,including the fluctuation of local strain energy,local atomic environment,electronegativity,etc.Here we report for the first time that the amplitude of the concentration wave can be mechani-cally tailored under cyclic deformation in a well-known Cantor alloy.Atomic-scale energy-dispersive X-ray spectroscopy(EDS)mapping reveals that cyclic deformation may dynamically induce the clustering of solute atoms with a size of 1-3 nm,thus resulting in a higher concentration wave amplitude.The con-centration wave promotes strong interactions between dislocations and local solute clusters.Aside from the typical Taylor strengthening contribution due to the presence of isolated dislocations,the strength enhancement from the mechanically induced composition fluctuations was quantified to be as high as∼70 MPa,about one-third of the yield strength of the alloy without pre-deformation.This opens up a novel strategy of designing high strength alloys by tailoring solute configurations.

关 键 词：Cantor alloy Cyclic deformation Concentration wave EDS maps 

分 类 号：TG139[一般工业技术—材料科学与工程]