The dislocation structure of slip bands in deformed high entropy alloy nanopillars  

作　　者：Qun Yang Yang Hu Jian-Min Zuo 

机构地区：[1]Department of Materials Science and Engineering,University of Illinois at Urbana-Champaign,Urbana,IL 61801,United States [2]School of Physical Science and Technology,Shanghai Tech University,Shanghai 201210,China [3]Frederick Seitz Materials Research Laboratory,University of Illinois at Urbana-Champaign,Urbana,Illinois 61801,United States

出　　处：《Journal of Materials Science & Technology》2021年第36期136-144,共9页材料科学技术（英文版）

基　　金：supported by the U.S.National Science Foundation(No.DMR-1410596 to J.M.Z);supported by the centre for High-resolution Electron Microscopy(ChEM)of SPST at Shanghai Tech University(No.EM02161943)。

摘　　要：Remarkable diversity is observed in dislocation interactions that are responsible for intermittent and sudden crystal slips.While large crystal slips can be easily observed on the surface of deformed crystals,unraveling the underlying dislocation interaction mechanisms,however,has been a longstanding challenge in the study of single-crystal plasticity.A recent study demonstrated that the sluggish dislocation dynamics in the high entropy alloy(HEA)of Al_(0.1)CoCrFeNi enables the observation of slip bands for a direct link to dislocation avalanches in a nanopillar.Here,we further examined the dislocation structure of slip bands in the HEA nanopillars oriented for single slip.Experimental evidence was provided on the dislocation organization in a slip band based on groups of primary dislocations,secondary dislocations,and dislocation pileups.The results were compared with the previously proposed slip band models.The unique aspects of the HEA that enable such observations were also investigated through an examination of the dislocation microstructure and its response to applied forces in the HEA nanopillars.

关 键 词：Crystal plasticity Dislocation structure NANOPILLARS High entropy alloy Slip band Transmission electron microscopy 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TG139[金属学及工艺—合金]