Chang, Hye Jung Oh, Hyun Seok Lee, Je In Park, Eun Soo 2024-01-19T23:33:08Z 2024-01-19T23:33:08Z 2021-09-03 2018-01 0264-1275 https://pubs.kist.re.kr/handle/201004/121805 In the present study, we report structural signature and size-dependent mechanical response of frozen-in icosahedral phase (I-phase) embedded in Zr-(Ti, Nb, Al)-(Cu, Ni) bulkmetallic glass (BMG)-forming alloys, which exhibit a narrowcomposition range overlapping between glass and I-phase forming region. Thus, the different sizes of the I-phase from tens of nanoscale precipitates to enhanced icosahedral short-range order in MG matrix can be obtained by controlling cooling history. I-phase particles with tens of nanoscale in BMGs do not contribute to extrinsic ductility due to limited blocking of the propagation of shear band. The shear band passes through the particle, splitting it into two pieces. On the other hand, BMGs with enhanced icosahedral short-range order, which can be evaluated by EXAFS analysis as well as calorimetric signal during isothermal annealing, exhibit enhanced ductility without strength reduction. Indeed, we examine the cut-off size of strain bursts and deformation dynamics of shear-avalanches through the statistical analysis of serration behavior. Icosahedral short-range order (ISRO)-embedded MGs exhibit weakened jammed state of the self-organized deformed zones, which results in the formation of numerous catastrophic deformed zones under relatively chaotic dynamics, and consequently multiple shear bands. These results would help deepen our understanding of the underlying mechanism that determines intrinsic ductility in BMGs via frozen-in ISRO, and ultimately give us a guideline for the design of promising BMGs with improved intrinsic ductility by manipulating local structural instability. (C) 2017 Elsevier Ltd. All rights reserved. English Elsevier BV Structural signature and size-dependent mechanical response of frozen-in icosahedral phase in bulk metallic glasses Article 10.1016/j.matdes.2017.10.049 1 Materials & Design, v.138, pp.129 - 139 Materials & Design 138 129 139 N scie scopus 000415114500013 2-s2.0-85032585119 Materials Science, Multidisciplinary Materials Science Article QUASI-CRYSTALLINE PHASE SHORT-RANGE ORDER NI-AL ALLOYS BEHAVIOR LIQUIDS PLASTICITY PD NUCLEATION DISORDER Metallic glass Icosahedral phase Structural instability Mechanical response Deformation dynamics