Article
Materials Science, Multidisciplinary
Y. H. Meng, S. Y. Zhang, W. H. Zhou, J. H. Yao, S. N. Liu, S. Lan, Y. Li
Summary: Structural relaxation and subsequent rejuvenation through thermal treatment can improve the plasticity and fracture toughness of metallic glasses. The recovery of loosely packed regions in the atomic structure during annealing contributes to the observed rejuvenation. Tailoring the mechanical properties of metallic glasses can be achieved by controlling the annealing and thermal treatment conditions.
Article
Multidisciplinary Sciences
Valerio Di Lisio, Isabella Gallino, Sascha Sebastian Riegler, Maximilian Frey, Nico Neuber, Golden Kumar, Jan Schroers, Ralf Busch, Daniele Cangialosi
Summary: The glass transition temperature of metallic glasses can be depressed by up to 40 K by reducing the sample size to below 10 & mu;m, allowing the attainment of glasses with low energy states. The properties of bulk metallic glasses are profoundly affected by reducing the sample size. By systematically reducing the length scale of gold and platinum-based metallic glasses, the vitrification behavior and atomic mobility were studied, revealing size-dependent vitrification kinetics in micrometer-sized glasses.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Tianding Xu, Xiao-Dong Wang, Eric M. Dufresne, Yang Ren, Qingping Cao, Dongxian Zhang, Jian-Zhong Jiang
Summary: The shape memory effect (SME) is found in annealed metallic glasses (MGs), where atoms can return to low-energy configurations through heating, extending the potential applications of MGs as functional materials.
Article
Materials Science, Ceramics
Qi Qiao, Zhengqing Cai, Ji Wang, Zijing Li, Shidong Feng, Zhen-Qiang Song, Li-Min Wang
Summary: The effects of adding niobium (Nb) on the glass-forming ability and mechanical properties of (Zr40Ti40Ni20)72Be28 bulk metallic glasses (BMGs) alloy system were studied. The addition of appropriate amounts of Nb weakens, then enhances the glass-forming ability of the alloy system and improves its thermal stability. Mechanical tests show that the addition of Nb enhances the room-temperature plasticity of the alloys, with a significant increase in compression deformation.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2023)
Article
Materials Science, Ceramics
A. S. Makarov, G. Afonin, R. A. Konchakov, J. C. Qiao, A. S. Aronin, N. P. Kobelev, V. A. Khonik
Summary: This study conducted parallel measurements of enthalpy and high-frequency shear modulus changes during structural relaxation of five bulk metallic glasses. The analysis revealed a one-to-one correlation between the change in molar enthalpy and the alteration in the calculated number of defects based on Interstitialcy theory. The defect formation enthalpy derived from this correlation aligns well with the accepted quantity in the Interstitialcy theory.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Chemistry, Physical
M. N. Liu, Q. Hao, J. Dong, B. A. Sun, S. D. Feng, D. Crespo, J. C. Qiao
Summary: It was found that the beta relaxation becomes more pronounced with the increase of copper in binary metallic glasses. However, the beta relaxation of CuZr or CuTi binary metallic glasses is much more modest compared to other metallic glasses.
Article
Chemistry, Physical
Xiaoqian Lu, Shidong Feng, Lin Li, Li-Min Wang, Riping Liu
Summary: This study tackles the challenge of identifying defects in metallic glasses by using atomic vibrational entropy from a thermodynamic perspective. The study reveals the critical role of vibrational entropy in bridging dynamics, thermodynamics, and structure in metallic glasses. The local vibrational entropy obtained by coarse-graining the atomic vibrational entropy in space effectively distinguishes between liquid-like and solid-like atoms and establishes a correlation with the structure of metallic glasses, offering a route to predict plastic events.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Review
Materials Science, Multidisciplinary
Baran Sarac, Juergen Eckert
Summary: This review provides an overview of the potential of bulk metallic glasses (BMGs) as net-shaping materials, their thermal processing capability, micro-/nano-structure, deformation behavior, and flow kinetics. It also discusses the variation of properties in the supercooled liquid region, high temperature deformation modeling, and applications of thermally-formed BMGs in various fields.
PROGRESS IN MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
S. F. Wei, X. D. Wang, K. K. Qiu, T. D. Xu, Q. P. Cao, S. Q. Ding, D. X. Zhang, J. Z. Jiang
Summary: In this study, the origins of pronounced and unpronounced beta-relaxation behaviors in Y60Ni16Al24 and Y60Fe16Al24 metallic glasses were elucidated using experimental and theoretical approaches. The results indicate that the atomic dynamics of mobile atoms are not only related to their local geometry, but also to their chemical compositions.
Article
Materials Science, Multidisciplinary
L. T. Zhang, Yun-Jiang Wang, Y. Yang, J. C. Qiao
Summary: In this study, the rejuvenation of metallic glasses through the training of the beta relaxation process is demonstrated. The transition from structural relaxation to rejuvenation is observed with increasing training frequency. Surprisingly, rejuvenation can be achieved at a relatively small cyclic strain of 0.2%. Rejuvenation increases relaxation enthalpy and promotes decoupling of the beta relaxation process and relaxation process. A cluster of beta relaxation time curves is formulated to describe energetic states between ultrastable and ultimately rejuvenated metallic glasses. Additionally, rejuvenation expands the distribution of the beta relaxation process, anelastic, and viscoplastic components during deformation.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Changjiu Chen, Zheng Yang, Bangjie Yin, Akihisa Inoue, Jinyong Zhang, Weiming Yang, Ze Sun, Qiaowen Luo, Zheng Chen, Yezeng He, Baolong Shen
Summary: The relaxation behavior and thermal stability of GdxNi20Al80-x (x = 50, 60, 65, 70 at%) metallic glasses were studied. The Gd70Ni20Al10 alloy exhibited the most significant relaxation phenomenon.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Nanoscience & Nanotechnology
X. Yuan, D. Sopu, F. Spieckermann, K. K. Song, S. Ketov, K. G. Prashanth, J. Eckert
Summary: Rejuvenation is the reverse process of relaxation in metallic glasses, which increases their free volume and brings them to a higher energy state. This study explores the controllable rejuvenation degree through a dilution procedure and identifies the maximum rejuvenation threshold. The activation of structural relaxation and the dynamic balance between free volume creation and annihilation determine the rejuvenation ability of metallic glasses. The highest degree of rejuvenation is related to the flow strain of the materials and exhibits a structure similar to shear bands.
SCRIPTA MATERIALIA
(2022)
Article
Physics, Multidisciplinary
Hui Wang, Wojciech Dmowski, Yang Tong, Zengquan Wang, Yoshihiko Yokoyama, Jittisa Ketkaew, Jan Schroers, Takeshi Egami
Summary: This study suggests that the plasticity of metallic glasses is related to the local atomic rearrangements under stress, rather than their atomic structure directly. By conducting experiments on various bulk metallic glasses, researchers found that the extent of local deviation from affine deformation within the elastic regime is strongly correlated with the plastic behavior of metallic glasses beyond yield.
PHYSICAL REVIEW LETTERS
(2022)
Article
Polymer Science
Ahmed Abdeldaym, Ralf Bruning
Summary: We investigated the changes of atactic polystyrene (a-PS) during annealing below the glass transition. Our measurements showed that upon relaxation, there was an increase in the diffuse diffraction peak and a decrease in the polymerization peak. These changes were proportional to the enthalpy changes and corresponded to a change in the fictive temperature. The relaxation signal exhibited a zero crossing at low scattering angles.
JOURNAL OF APPLIED POLYMER SCIENCE
(2022)
Article
Chemistry, Physical
Valerio Di Lisio, Vasiliki-Maria Stavropoulou, Daniele Cangialosi
Summary: The kinetics of physical aging in small molecules interacting via van der Waals forces was studied over a wide temperature range. The a relaxation was found to be generally adequate in describing aging at temperatures close to the glass transition, but failed to capture the time-dependent evolution of the glass thermodynamic state at low aging temperatures. The results suggest that different molecular mechanisms are involved in the equilibration of glass under a wide range of aging conditions.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Y. J. Duan, J. C. Qiao, D. Crespo, E. V. Goncharova, A. S. Makarov, G. V. Afonin, V. A. Khonik
JOURNAL OF ALLOYS AND COMPOUNDS
(2020)
Article
Physics, Multidisciplinary
Qi Hao, Ji-Chao Qiao, E. Goncharova, G. Afonin, Min-Na Liu, Yi-Ting Cheng, V. A. Khonik
Article
Materials Science, Multidisciplinary
Andrei Makarov, Gennadii Afonin, Yurii Mitrofanov, Nikolai Kobelev, Vitaly Khonik
Article
Physics, Multidisciplinary
A. S. Makarov, E. V. Goncharova, G. V. Afonin, J. C. Qiao, N. P. Kobelev, V. A. Khonik
Article
Chemistry, Physical
V. A. Khonik
Summary: Professor A.V. Granato is a key scientist known for his contributions to understanding dislocation relaxations in crystals. He also proposed the Interstitialcy theory (IT) which offers new insights on melting, equilibrium/supercooled liquids and glasses in relation to the maternal crystalline state. This theory's origins, basic results, and recent developments are briefly discussed in the article.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Multidisciplinary
R. A. Konchakov, A. S. Makarov, A. S. Aronin, N. P. Kobelev, V. A. Khonik
Summary: Molecular dynamics simulations of aluminum near its melting point show a significant increase in vibrational entropy of interstitial defects with dumbbell configuration. By estimating the density of these defects in the melt through three independent methods, the configurational entropy of the system with defects is determined. Approximately 70% of the total entropy of melting can be attributed to the generation of interstitial dumbbells at T = T-m.
Article
Materials Science, Ceramics
A. S. Makarov, G. Afonin, R. A. Konchakov, J. C. Qiao, A. S. Aronin, N. P. Kobelev, V. A. Khonik
Summary: This study conducted parallel measurements of enthalpy and high-frequency shear modulus changes during structural relaxation of five bulk metallic glasses. The analysis revealed a one-to-one correlation between the change in molar enthalpy and the alteration in the calculated number of defects based on Interstitialcy theory. The defect formation enthalpy derived from this correlation aligns well with the accepted quantity in the Interstitialcy theory.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Physics, Condensed Matter
A. S. Makarov, J. C. Qiao, N. P. Kobelev, A. S. Aronin, V. A. Khonik
Summary: This study focuses on the fragility of supercooled liquids, demonstrating the relationship between fragility and high-frequency shear modulus. The heat capacity jump is also found to be related to fragility and shear modulus relaxation. The results suggest that the evolution of interstitial-type defects frozen-in during glass production mediates the connection between fragility, heat capacity jump, and high-frequency shear modulus in the supercooled liquid state.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Physical
N. P. Kobelev, J. C. Qiao, A. S. Makarov, A. M. Glezer, V. A. Khonik
Summary: The study reports measurements of internal friction and shear modulus of glassy Cu49Hf42Al9 at different frequencies and temperatures. It is found that the relaxation of internal friction and shear modulus decreases with increasing frequency in the investigated range. A new method for determining the Gibbs activation energy of relaxation is derived, and the underlying activation energy spectrum is found to smoothly increase with accessible activation energies in the experiment.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Condensed Matter
A. S. Makarov, G. Afonin, J. C. Qiao, A. M. Glezer, N. P. Kobelev, V. A. Khonik
Summary: By performing calorimetric and shear modulus measurements on bulk metallic glasses, this study demonstrates the consistency between the calorimetric determination and calculation of excess thermodynamic potentials, with a focus on the physical origin of these potentials being related to a system of interstitial-type defects frozen-in from the liquid state. The estimates of defect formation enthalpy and entropy indicate that the enthalpy scales with the shear modulus while the entropy is significantly large, aligning with the basic assumptions of the interstitialcy theory.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Physics, Condensed Matter
A. S. Makarov, G. Afonin, A. S. Aronin, N. P. Kobelev, V. A. Khonik
Summary: A novel approach is presented in this paper to understand the heat effects caused by structural relaxation of metallic glasses. By applying a general thermodynamic equation, the entropy change in glass relaxation can be determined, and the kinetics of the heat effects controlled by defect-induced structural relaxation can be calculated. The experimental results show a good agreement with the calculated results.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Materials Science, Multidisciplinary
Andrei Makarov, Marina Kretova, Gennadii Afonin, Nikolai Kobelev, Vitaly Khonik
Summary: This study conducted high-precision measurements of the temperature dependences of the shear modulus G in bulk metallic glass. It found that plastic deformation significantly affects the anharmonic, electronic, and relaxation components of G, with the relaxation contribution increasing, anharmonic component increasing, and electronic component decreasing.
Article
Nanoscience & Nanotechnology
A. S. Makarov, G. V. Afonin, R. A. Konchakov, V. A. Khonik, J. C. Qiao, A. N. Vasiliev, N. P. Kobelev
Summary: By introducing a dimensionless order parameter 4, the structural order of glass can be estimated, and this parameter shows a strong correlation with the glass-forming ability.
SCRIPTA MATERIALIA
(2024)
Article
Chemistry, Physical
A. S. Makarov, R. A. Konchakov, J. C. Qiao, A. N. Vasiliev, N. P. Kobelev, V. A. Khonik
Summary: This study investigates the relationship between defect concentration and the structure factor of glasses based on shear modulus measurements and molecular dynamics simulation. The results show that defect-induced disordering is independent of glass thermal prehistory above the glass transition temperature, while significant differences exist between initial and relaxed samples below the transition temperature.
Article
Physics, Multidisciplinary
M. A. Kretova, R. A. Konchakov, N. P. Kobelev, V. A. Khonik