A comprehensive review of a novel promising framework for the understanding of non-crystalline metallic materials, i.e., interstitialcy theory of condensed matter states（ITCM）, is presented. The background of the IT...A comprehensive review of a novel promising framework for the understanding of non-crystalline metallic materials, i.e., interstitialcy theory of condensed matter states（ITCM）, is presented. The background of the ITCM and its basic results for equilibrium/supercooled liquids and glasses are given. It is emphasized that the ITCM provides a new consistent, clear, and testable approach, which uncovers the generic relationship between the properties of the maternal crystal,equilibrium/supercooled liquid and glass obtained by melt quenching.展开更多
A relationship between thermal effects and relaxation of the high-frequency shear modulus upon heat treatment of bulk Zr48(Cu5/6Ag1/6)44Al8 metallic glass is found.This relationship is attributed to the relaxation of ...A relationship between thermal effects and relaxation of the high-frequency shear modulus upon heat treatment of bulk Zr48(Cu5/6Ag1/6)44Al8 metallic glass is found.This relationship is attributed to the relaxation of a interstitial-type defect system frozen-in from the melt upon glass production.Calorimetric data show that thermal effects occurring on heating include heat release below the glass transition temperature,heat absorption above it and heat release caused by crystallization.The equation derived within the Interstitialcy theory can be used to calculate the shear modulus relaxation using the calorimetric data.The obtained results are used to trace the defect concentration as functions of temperature and thermal prehistory.展开更多
Pd_(40)Ni_(40)P_(20)(at.%)samples with different enthalpy states were fabricated through high-pressure torsion or sub-Tg annealing of the as-cast material.Subsequently,the underlying structural relaxation was studied ...Pd_(40)Ni_(40)P_(20)(at.%)samples with different enthalpy states were fabricated through high-pressure torsion or sub-Tg annealing of the as-cast material.Subsequently,the underlying structural relaxation was studied by in-situ shear modulus measurements and modulated differential scanning calorimetry.The results show that high-pressure torsion leads to shear modulus softening and an increase of the nonreversible exothermic enthalpy,indicating a significant structural rejuvenation,while sub-Tg annealing causes shear modulus hardening and a decrease of the nonreversible exothermic enthalpy.The reversible endothermic effect which can reflect the fractional change of supercooled liquid with temperature was found to be almost identical for all samples,and independent of deformation or thermal history.The total heat flow can be well correlated with the shear modulus within the framework of interstitialcy theory.Furthermore,we demonstrate that the structural relaxation below Tg decouples into internal stress relaxation andβ-relaxation.In addition,this work indicates that the processes ofα-relaxation andβ-relaxation in the metallic glass are of similar structural origin but occur on different spatial scales.展开更多
基金supported by the Ministry of Education and Science of the Russian Federation(Grant No.3.114.2014/K)
文摘A comprehensive review of a novel promising framework for the understanding of non-crystalline metallic materials, i.e., interstitialcy theory of condensed matter states（ITCM）, is presented. The background of the ITCM and its basic results for equilibrium/supercooled liquids and glasses are given. It is emphasized that the ITCM provides a new consistent, clear, and testable approach, which uncovers the generic relationship between the properties of the maternal crystal,equilibrium/supercooled liquid and glass obtained by melt quenching.
基金the National Natural Science Foundation of China(Grant No.51971178)the Astronautics Supporting Technology Foundation of China(Grant No.2019-HT-XG)+2 种基金the Natural Science Foundation of Shaanxi Province,China(Grant No.2019JM-344)the Russian Science Foundation(Grant No.20-62-46003)the Fundamental Research Funds for the Central Universities,China(Grant Nos.3102019ghxm007 and 3102017JC01003).
文摘A relationship between thermal effects and relaxation of the high-frequency shear modulus upon heat treatment of bulk Zr48(Cu5/6Ag1/6)44Al8 metallic glass is found.This relationship is attributed to the relaxation of a interstitial-type defect system frozen-in from the melt upon glass production.Calorimetric data show that thermal effects occurring on heating include heat release below the glass transition temperature,heat absorption above it and heat release caused by crystallization.The equation derived within the Interstitialcy theory can be used to calculate the shear modulus relaxation using the calorimetric data.The obtained results are used to trace the defect concentration as functions of temperature and thermal prehistory.
基金financial support by German Research Foundation under the grant No.W11899/29-1the China Scholarship Council for its financial supportthe financial support from Russian Science Foundation under the grant No.20-62-46003(measurements of the shear modulus and discussion on the results)。
文摘Pd_(40)Ni_(40)P_(20)(at.%)samples with different enthalpy states were fabricated through high-pressure torsion or sub-Tg annealing of the as-cast material.Subsequently,the underlying structural relaxation was studied by in-situ shear modulus measurements and modulated differential scanning calorimetry.The results show that high-pressure torsion leads to shear modulus softening and an increase of the nonreversible exothermic enthalpy,indicating a significant structural rejuvenation,while sub-Tg annealing causes shear modulus hardening and a decrease of the nonreversible exothermic enthalpy.The reversible endothermic effect which can reflect the fractional change of supercooled liquid with temperature was found to be almost identical for all samples,and independent of deformation or thermal history.The total heat flow can be well correlated with the shear modulus within the framework of interstitialcy theory.Furthermore,we demonstrate that the structural relaxation below Tg decouples into internal stress relaxation andβ-relaxation.In addition,this work indicates that the processes ofα-relaxation andβ-relaxation in the metallic glass are of similar structural origin but occur on different spatial scales.
