Bulk metallic glasses(BMGs)are thermodynamically metastable.As such,crystallization occurs when a BMG is thermally annealed at a temperature above the glass transition temperature.While extensive studies have been performed on the crystallization kinetics of BMGs,most of them have focused on the amorphous-to-crystalline structural ordering,and little attention has been paid to chemical distribution and its relationship with the structural ordering during the crystallization process.In this paper,a new approach,with simultaneous differential scanning calorimetry(DSC)and small angle neutron scatter-ing(SANS)measurements,was applied to study in situ the crystallization of a Zr45.5Cu45.5Al9 BMG upon isothermal annealing at a temperature in the supercooled liquid region.Quantitative analysis of the DSC and SANS data showed that the structural evolution during isothermal annealing could be classified into three stages:(1)incubation;(Ⅱ)amorphous-to-crystalline structural ordering;(Ⅲ)continuous chemical redistribution.This finding was validated by composition analysis with atom probe tomography(APT),which further identified a transition region formed by expelling Al into the matrix.The transition re-gion,with a composition of(Cu,Al)50Zr50,served as an intermediate step facilitating the formation of a thermodynamically stable crystalline phase with a composition of(Cu,Al)i0Zr7.

Xuelian Wu;Si Lan;Xiyang Li;Ming Yang;Zhenduo Wu;Xiaoya Wei;Haiyan He;Muhammad Naeem;Jie Zhou;Zhaoping Lu;Elliot Paul Gilbert;Dong Ma;Xun-Li Wang

Department of Physics,City University of Hong Kong,Hong Kong,China;Herbert Gleiter Institute of Nanoscience,School of Materials Science and Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;Quantum Matter Institute,University of British Columbia,Vancouver,British Columbia V6T 1Z4,Canada;Neutron Sciences Platform,Songshan Lake Materials Laboratory,Dongguan 523808,China;Center for Neutron Scattering and Applied Physics,City University of Hong Kong Dongguan Research Institute,Dongguan 523000,China;State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,China;Australian Centre for Neutron Scattering,Australian Nuclear Science and Technology Organisation,Lucas Heights,New South Wales 2234,Australia;City University of Hong Kong Shenzhen Research Institute,Shenzhen 518057,China

材料科学技术（英文版）

[1]Xuelian Wu;Si Lan;Xiyang Li;Ming Yang;Zhenduo Wu;Xiaoya Wei;Haiyan He;Muhammad Naeem;Jie Zhou;Zhaoping Lu;Elliot Paul Gilbert;Dong Ma;Xun-Li Wang-.Continuous chemical redistribution following amorphous-to-crystalline structural ordering in a Zr-Cu-Al bulk metallic glass)[J].材料科学技术（英文版）,2022(06):285-293

BMGs,Zr45,5Cu45,5Al9,expelling,50Zr50,i0Zr7

Continuous,chemical,redistribution,following,amorphous,crystalline,structural,ordering,bulk,metallic,Bulk,glasses,are,thermodynamically,metastable,such,crystallization,occurs,when,thermally,annealed,temperature,above,transition,While,extensive,studies,have,been,performed,kinetics,most,them,focused,little,attention,paid,its,relationship,during,process,In,this,paper,new,approach,simultaneous,differential,scanning,calorimetry,DSC,small,angle,neutron,scatter,SANS,measurements,was,applied,study,situ,upon,isothermal,annealing,supercooled,liquid,region,Quantitative,analysis,data,showed,that,evolution,could,classified,into,three,stages,incubation,continuous,This,finding,validated,by,composition,atom,probe,tomography,APT,which,further,identified,matrix,served,intermediate,step,facilitating,formation,phase

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