Article
Chemistry, Physical
Aditya Kamath, Fei Long, Segun Aiyeru, Malcolm Griffiths, Artur Tamm, Mark R. Daymond, Laurent Karim Beland
Summary: Zirconium alloys, specifically Zr-2.5Nb, are widely used in nuclear energy applications as pressure tube material in reactors. By analyzing the crystal structure of Zr((Zr,) Nb,Fe)2 NPs using TEM, DFT calculations, and FEA, we uncover a mixed c14 and c15 Laves phase structure within the NPs and provide an explanation through the syncroshear mechanism. Through thermodynamic analysis, we evaluate the contributions to the free energy of the NPs and find that the c15 structure is energetically favored at lower temperatures, while the c14 structure prevails at higher temperatures. Additionally, our study reveals that the NP/a-Zr interface is likely to be incoherent due to significant stresses involved.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
S. S. Acharya, V. R. R. Medicherla, Komal Bapna, Khadiza Ali, Deepnarayan Biswas, Rajeev Rawat, Kalobaran Maiti
Summary: The study investigates the ground state properties of Invar alloys by examining the electronic structure of Fe1-xNix alloys. Anomalous behavior and emergence of distinct features in core levels at low temperatures suggest the existence of mixed phase in the ground state of Invar alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Thermodynamics
M. R. Tolosa, G. Aurelio, D. Arias, R. Gonzalez, N. Nieva
Summary: The Fe-rich corner of the Fe-Nb-Zr phase diagram was investigated at 1000 degrees C using SXPD technique and EPMA. The structures of MgCu2 (C15) and MgZn2 (C14), corresponding to Fe2Zr and Fe2Nb Laves phases, were observed. However, the MgNi2 (C36) structure, corresponding to Fe-2(Zr1-xNbx) Laves phase, was not found at this temperature. The present work proposes the existence of two three-phase fields and five two-phase fields.
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Wenjie Li, Kun Lin, Yu Yan, Chengyi Yu, Yili Cao, Xin Chen, Chin-Wei Wang, Kenichi Kato, Yan Chen, Ke An, Qinghua Zhang, Lin Gu, Qiang Li, Jinxia Deng, Xianran Xing
Summary: A high-performance alloy, Zr0.8Ta0.2Fe1.7Co0.3, with isotropic zero thermal expansion (ZTE) behavior, high corrosion resistance, and excellent thermal and structural stability, is reported. The multiple stabilities are attributed to the alloy's cubic symmetry, controllable magnetic order, and the formation of a passive film with Ta and Zr chemical modifications. The alloy has the potential for robust applications in marine services and other fields.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Huang Liu, Jingxi Zhang, Chengshang Zhou, Pei Sun, Yong Liu, Zhigang Zak Fang
Summary: This paper investigates the effect of Nb alloying on the microstructure and hydrogen storage properties of Ti-Fe-Zr-Mn-Nbx alloys. The addition of 2% Nb enables a good combination of the hydrogen capacity and activation property, while Zr-rich phases play a critical role in the activation behavior. However, high Nb addition (> 4%) leads to the reduction of Zr-rich phases and deteriorates the activation kinetics. Nb addition also promotes the formation of the TiFe main phase and increases capacities at ambient temperature. The correlations between microstructure and hydrogen storage performance provide insights into tailoring hydrogen storage properties by alloying TiFe with multi-elements.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Wei Jiang, Yi Peng, Yuchen Mao, Hui Wang, Liuzhang Ouyang, Runze Yu, Changqing Jin, Min Zhu
Summary: In this study, high pressure solidification was successfully used to obtain a metastable Y0.7Zr0.24Ti0.06Fe2 alloy with supersaturated Ti in the YFe2 based C15 Laves phase. The segregation of Ti, Y, Zr and multi-phase formation were suppressed, and the resulting HPS alloy consisted of primary C15 phase (C15-1) and secondary C15 phase (C15-2) with 77.1% and 22.9% of the total content, respectively. Additionally, the hydrogen absorption and desorption capacities were substantially increased. This study demonstrates that the combination of high-pressure solidification and alloying is an effective method for exploring new hydrogen storage materials with metastable structure and high performance.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Wei Jiang, Yi Peng, Yuchen Mao, Hui Wang, Liuzhang Ouyang, Runze Yu, Changqing Jin, Min Zhu
Summary: In this study, a metastable hydrogen storage alloy was successfully synthesized using high pressure solidification, which exhibited improved hydrogen absorption and desorption capacities. The findings demonstrate that the combination of high pressure solidification and alloying is an effective method for exploring new high-performance hydrogen storage materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Fabio Martins Cardoso, Cristina Bormio-Nunes
Summary: The study successfully prepared a FeCoNi(GaNb)(0.20) multicomponent alloy with low magnetostriction and high permeability values, suitable for use in electric machines and magnetic devices in the subkilohertz frequency range.
ADVANCED ENGINEERING MATERIALS
(2021)
Article
Chemistry, Physical
Bing Tu, Hui Wang, Yin Wang, Rui Li, Liuzhang Ouyang, Renheng Tang
Summary: In this work, Ti-Zr-Cr-based AB(2)-type Ti-based alloys with progressive Mn, Ni, and V substitutions were developed for reversible hydrogen storage under ambient conditions. The optimized alloy (Ti0.8Zr0.2)(1.1)Mn1.2Cr0.55Ni0.2V0.05 exhibited good hydrogen storage performance, making it suitable for use in hybrid hydrogen tank of fuel cell bicycles.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Wenjie Wang, Kaihuai Yang, Qianting Wang, Pinqiang Dai, Hui Fang, Fangjuan Wu, Qiaohang Guo, Peter K. Liaw, Nengbin Hua
Summary: In this study, TiZrHfNbFex refractory high-entropy alloys (HEAs) were developed and their microstructure, mechanical properties, corrosion resistance, and wear resistance were investigated. The TiZrHfNbFe0.5 alloy exhibited excellent overall mechanical properties and superior corrosion resistance. Additionally, the wear resistance of the alloy increased with the increase in Fe content.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
George Kim, Qing Gu, Philip Nash, Wei Chen
Summary: The properties of ternary Laves phases depend on the wide solubility ranges and site preferences of alloying elements, influencing performance significantly.
Article
Engineering, Biomedical
Gabriela Strnad, Laszlo Jakab-Farkas, Federico Simone Gobber, Ildiko Peter
Summary: Nanoporous/nanotubular complex oxide layers were successfully developed on high-fraction beta phase quaternary Ti-Nb-Zr-Ta and Ti-Nb-Zr-Fe promising biomedical alloys with a low elasticity modulus through electrochemical anodization. The morphology of the nanostructures exhibited inner diameters of 15-100 nm. The oxide layers were characterized using SEM, EDS, XRD, and current evolution analyses. Optimized process parameters of electrochemical anodization resulted in the synthesis of complex oxide layers with pore/tube openings of 18-92 nm on Ti-10Nb-10Zr-5Ta, 19-89 nm on Ti-20Nb-20Zr-4Ta, and 17-72 nm on Ti-29.3Nb-13.6Zr-1.9Fe alloys using specific electrolytes.
JOURNAL OF FUNCTIONAL BIOMATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Camilo A. F. Salvador, Mariana R. Dal Bo, Dalton D. Lima, Caetano R. Miranda, Rubens Caram
Summary: Among the investigated beta-metastable alloys in the Ti-Nb-Fe-Zr system for biomedical applications, the addition of Fe as a minor alloying element has been explored to improve mechanical properties. The results show that Ti-23Nb-2.0Fe-10Zr alloy stands out with the best combination of mechanical strength and elastic modulus after aging, indicating great potential for biomedical applications.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
De-chuan Yu, Chong-wei Zheng, Qiong Qin, Chun-xin Li, Xue-hong Li, Di Wu, Yang Qi, Hai-feng Zhang, Yong Wang, Yue Yu
Summary: The effects of Nb microalloying on the glass forming ability, thermal properties, and mechanical properties of the alloys were investigated. It was found that the addition of Nb could enhance the glass forming ability and improve the plastic strain at room temperature.
MATERIALS RESEARCH EXPRESS
(2022)
Article
Nanoscience & Nanotechnology
Vidur Tuli, Antoine Claisse, Patrick A. Burr
Summary: A fast and accurate method for predicting hydrogen solubility and trapping in alloys is presented, which is much faster than conventional approaches. The method is validated by studying hydrogen redistribution in nuclear fuel cladding. The results show that hydrogen solubility and redistribution are influenced by alloy composition and irradiation.
SCRIPTA MATERIALIA
(2022)
Article
Crystallography
Lukas Kyvala, Maxim Tchaplianka, Alexander B. Shick, Sergii Khmelevskyi, Dominik Legut
Article
Physics, Condensed Matter
Arsenii Gerasimov, Lars Nordstrom, Sergii Khmelevskyi, Vladimir V. Mazurenko, Yaroslav O. Kvashnin
Summary: This study investigates the magnetic moments of iron and cobalt in their B2-ordered alloy using a combination of density functional theory and dynamical mean-field theory. The results suggest that the Co magnetic moment strongly depends on the directions of surrounding magnetic moments, indicating a Stoner-type mechanism of magnetism. The study highlights the essential role of local correlations in stabilizing the local moment on Co in the absence of magnetic order at high temperatures.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Materials Science, Multidisciplinary
Radu Abrudan, Martin Hennecke, Florin Radu, Torsten Kachel, Karsten Holldack, Rolf Mitzner, Andreas Donges, Sergii Khmelevskyi, Andras Deak, Laszlo Szunyogh, Ulrich Nowak, Stefan Eisebitt, Ilie Radu
Summary: Experimental and theoretical evidence demonstrates the existence of element-specific magnetic damping parameters in the ultrafast magnetization response of a high-anisotropy ferrimagnetic DyCo5 alloy to femtosecond laser excitation. The significantly different demagnetization and remagnetization dynamics of Dy and Co magnetic moments are linked to their element-specific spin-orbit coupling strengths. These findings can be utilized for tuning the speed and magnitude of laser-driven magnetic processes in multicomponent magnetic materials.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
Leonid Pourovskii, Sergii Khmelevskyi
Summary: This passage discusses the nature of order in low-temperature phases of certain materials and the hidden orders that may spark research interest. By studying neptunium dioxide NpO2, it is found that the ground-state order and magnetic excitations can be fully described by a low-energy Hamiltonian, revealing the multipolar exchange mechanism behind the anomalous volume contraction of the NpO2 HO phase.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Physics, Multidisciplinary
Yili Cao, Kun Lin, Sergii Khmelevskyi, Maxim Avdeev, Keith M. Taddei, Qiang Zhang, Qingzhen Huang, Qiang Li, Kenichi Kato, Chiu Chung Tang, Alexandra Gibbs, Chin-Wei Wang, Jinxia Deng, Jun Chen, Hongjie Zhang, Xianran Xing
Summary: By adjusting the Fe-Co content, researchers have optimized the thermal expansion behavior in a family of R-2(Fe, Co)(17) materials, achieving a record-wide SIV range with good cyclic stability. This breakthrough paves the way for exploiting thermal-expansion-control engineering and related functional materials.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Applied
M. Parzer, F. Garmroudi, A. Riss, S. Khmelevskyi, T. Mori, E. Bauer
Summary: This paper explores the aluminum-rich region in the Fe-V-Al material system and proposes a promising approach to improve the thermoelectric properties of p-type Heusler alloys. Experimental results show that Fe2VAlx alloys with high Al solubility exhibit significantly increased thermopower and reduced thermal conductivity. The analysis suggests that the enhancement is likely attributed to the formation of a resonant state at the valence band edge, which is supported by density-functional-theory calculations. This work paves the way for the development of p-type full-Heusler materials with enhanced thermoelectric performance.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Bence Bernath, Khrystyna Kutko, Steffen Wiedmann, Olga Young, Hans Engelkamp, Peter C. M. Christianen, Sergii Poperezhai, Leonid Pourovskii, Sergii Khmelevskyi, Dmytro Kamenskyi
Summary: The magnetostriction phenomenon is widely present in magnetically ordered materials and has broad application potential in high-tech fields such as precision machinery and robotics. This study reports a remarkable magnetostrictive response in the insulator paramagnet KEr(MoO4)(2), demonstrating that the anomaly is driven by a single-ion effect through a strong coupling between Er3+ ions and the crystal lattice. The microscopic mechanism behind the massive magnetostrictive response is revealed through a combination of low-temperature magnetization measurements, dilatometry, and ab initio calculations.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Multidisciplinary Sciences
Fabian Garmroudi, Michael Parzer, Alexander Riss, Andrei V. Ruban, Sergii Khmelevskyi, Michele Reticcioli, Matthias Knopf, Herwig Michor, Andrej Pustogow, Takao Mori, Ernst Bauer
Summary: Researchers have discovered a rare and unique molecular structure that can be manipulated by changing temperature and pressure, offering new possibilities for the manufacture of novel materials.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Sergii Khmelevskyi, Peter Mohn
Summary: The magnetism of Co2FeSi alloy is studied using first-principles calculations. Fe and Co in Co2FeSi exhibit different magnetic behaviors, with Fe moments being localized and Co moments being itinerant. The inter-atomic exchange interactions between Fe and Co are strongly renormalized by magnetic disorder.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Fabian Garmroudi, Michael Parzer, Alexander Riss, Simon Beyer, Sergii Khmelevskyi, Takao Mori, Michele Reticcioli, Ernst Bauer
Summary: This study demonstrates a method to significantly increase the thermoelectric power of semimetallic Heusler alloys by transferring electronic states from within the pseudogap to higher energies. Experimental measurements on co-substituted systems show exceptionally large thermoelectric power factors.
MATERIALS TODAY PHYSICS
(2022)
Article
Multidisciplinary Sciences
Fabian Garmroudi, Michael Parzer, Alexander Riss, Cedric Bourges, Sergii Khmelevskyi, Takao Mori, Ernst Bauer, Andrej Pustogow
Summary: Unprecedented thermoelectric performance was discovered in NixAu1-x alloys, which challenges the common belief that good metals are not suitable for thermoelectric materials and provides a new approach for high thermoelectric performance.
Article
Materials Science, Multidisciplinary
S. Khmelevskyi, L. Pourovskii, E. A. Tereshina-Chitrova
Summary: The recently discovered UTe2 superconductor is a heavy-fermion mixed-valence system with peculiar properties. It shows no magnetic order but has strong anisotropy of magnetic susceptibility and superconducting critical field. By using dynamical mean-field theory calculations, it is found that the crystal-field splitting of the 5 f 2 ionic configuration derived from first principles agrees with experimental observations. The normal paramagnetic state of UTe2 is analogous to that of URu2Si2 in the Kondo arrest scenario.
Article
Materials Science, Multidisciplinary
Dario Fiore Mosca, Leonid Pourovskii, Beom Hyun Kim, Peitao Liu, Samuele Sanna, Federico Boscherini, Sergii Khmelevskyi, Cesare Franchini
Summary: In this work, the complex entanglement between spin interactions, electron correlation, and Janh-Teller structural instabilities in the 5d(1) J(eff) = 3/2 spin-orbit coupled double perovskite Ba2NaOsO6 is studied using first principles approaches. The origin of the observed quadrupolar canted antifferomagnetic is elucidated by combining noncollinear magnetic calculations with multipolar pseudospin Hamiltonian analysis and many-body techniques. It is found that the transition between different magnetic orders can be controlled by the strength of electronic correlation and the degree of Jahn-Teller distortions.
Article
Materials Science, Multidisciplinary
F. Garmroudi, A. Riss, M. Parzer, N. Reumann, H. Mueller, E. Bauer, S. Khmelevskyi, R. Podloucky, T. Mori, K. Tobita, Y. Katsura, K. Kimura
Summary: This study quantitatively analyzed the thermoelectric properties of Fe2V1-xTaxAl1-ySiy compounds, revealing an increase in band gap and Seebeck coefficient with Ta substitution, leading to an enhanced power factor with the highest value reported near room temperature. Additionally, the dominant scattering mechanisms of electrons were found to be fundamentally different between p-type and n-type materials.
Article
Materials Science, Multidisciplinary
J. Kudrnovsky, V Drchal, F. Maca, I Turek, S. Khmelevskyi
