Review
Materials Science, Multidisciplinary
Kai Xu, Chengcheng Zhan, Ming Lou, Xuelian Xiao, Ruonan Zhou, Fangming Wang, Xiaofei Hu, Yuan Yuan, Keke Chang
Summary: Rare-earth elements, also known as industrial vitamins, are widely used in modern lives, especially in high-tech applications. Despite their close chemical similarities, these elements have different characteristics. The microalloying effect of rare-earth elements is crucial for improving the properties of materials, and the study of phase diagrams related to rare-earth elements is essential for the design and optimization of materials. However, the knowledge in this area is relatively scarce compared to commonly-used elements.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Yikun Zhang, Weixiang Hao, Chenglong Hu, Xing Wang, Xuefeng Zhang, Lingwei Li
Summary: Magnetic refrigeration technology based on the magnetocaloric effect is considered as a prominent, energy-efficient, and environmentally friendly cooling method. A rare-earth-free magnetocaloric material family has been identified, which exhibits room-temperature refrigeration performance and can be fabricated from low-cost, abundant, and non-toxic elements, providing new choices for practical magnetic refrigeration applications.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
L. L. Bao, H. Yibole, J. Y. Xu, Z. Q. Ou, O. Haschuluu, O. Tegus, N. H. van Dijk, E. Bruck, F. Guillou
Summary: (English Summary:)
This study explores the structural and magnetic phase diagrams of (Fe,Co)(2)(P,Si) compounds, with a focus on the observation range of the hexagonal Fe2P-type structure. It is found that under certain conditions of Si content and Fe substitution for Co, the samples undergo structural distortion and exhibit different crystal structures. Additionally, simultaneous Co substitution for Fe and Si substitution for P helps to observe the hexagonal structure. This study provides guidance for future investigations in determining the desired range of properties for permanent magnetic applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Multidisciplinary
Heng-An Zhou, Jiahao Liu, Zidong Wang, Qihan Zhang, Teng Xu, Yiqing Dong, Le Zhao, Soong-Geun Je, Mi-Young Im, Kun Xu, Jing Zhu, Wanjun Jiang
Summary: This report presents a new class of spintronics materials, demonstrating the stabilization of skyrmions and skyrmionium-like spin textures in Pt/SmCo5/Ta and Pt/SmCo5/Ir multilayers through interface engineering. Micromagnetic simulations confirm the presence of chiral spin textures in this new material family, suggesting rare earth permanent magnets as a potential platform for studying interfacial chiral spintronics.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
A. M. Gabay, Chaoya Han, Chaoying Ni, G. C. Hadjipanayis
Summary: Recently, the lack of knowledge about the high-temperature phase equilibria in the Sm-Fe-Ti system has been brought to attention due to new attempts in developing high-performance rare-earth-lean permanent magnets based on the Sm(Fe,Ti)12 compound. Experimental investigation has revealed inaccuracies in the currently accepted phase relations, leading to a revision of the Fe-rich corner of the Sm-Fe-Ti phase diagram. The study also found extended Ti ranges for the Sm(Fe,Ti)12 and Sm3(Fe,Ti)29 phases, and identified the equilibrium between the Sm2(Fe,Ti)17 and TiFe2 phases. The revised phase diagram is essential for the manufacturing of Sm (Fe,Ti)12-based permanent magnets via liquid-phase sintering.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
A. M. Gabay, Chaoya Han, Chaoying Ni, G. C. Hadjipanayis
Summary: Iron-rich corners of Sm-Fe-Ti phase diagram and quasi-ternary Sm-Fe0.8Co0.2-Ti phase diagrams are constructed based on experimental investigation. The existence of a high-temperature Th2Ni17-type phase is confirmed. The composition, equilibria, and magnetic anisotropy of cobalt-substituted phases are established.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Zhen Li, Xiao-Bao Li, Mark E. Light, Anna E. Carrillo, Ana Arauzo, Manuel Valvidares, Claudio Roscini, Francesc Teixidor, Clara Vinas, Felipe Gandara, Elena Bartolome, Jose Giner Planas
Summary: This work demonstrates the successful synthesis of a multi-metallic MTV RE MOF incorporating two, four, six, or eight different RE ions without any compositional segregation. The incorporation of all RE cations is characterized via compositional and structural characterization. The more complex MTV MOF, including all eight RE ions, is characterized using optical, thermal, and magnetic techniques.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Shulan Zuo, Kaiming Qiao, Ying Zhang, Tongyun Zhao, Chengbao Jiang, Baogen Shen
Summary: In a centrosymmetric rhombohedral Nd2Co17 magnet, spontaneous biskyrmions are observed, which evolve into enclosed in-plane domains with nanometric size due to the enhancement of planar magnetic anisotropy. The generation of biskyrmion lattice and its evolution demonstrate the crucial role of intrinsic bi-anisotropy and demagnetization effects.
Article
Chemistry, Physical
Munzali Musa, Xianglong Zhou, Xin Song, Tao Yuan, Wentao Jia, Jingdong Wang, Tianyu Ma
Summary: This study investigates the influence of increasing iron content on the microstructure of high temperature permanent magnets Sm-Co-Fe-Cu-Zr, showing that higher iron content leads to increased 2:17R ordering degree and decreased stacking faults density, resulting in larger nanocell sizes.
Article
Chemistry, Physical
Guangzong Xing, Takahiro Ishikawa, Yoshio Miura, Takashi Miyake, Terumasa Tadano
Summary: This study investigates the thermodynamic stability of binary R1-xFex compounds using first-principles calculations based on density functional theory at finite temperature. The findings show that entropy contributions, including electronic and vibrational free energies, are essential for accurately predicting the stability of these alloys. The results indicate that vibrational entropy plays a key role in stabilizing various R1-xFex compounds with increasing temperature, suggesting the possibility of synthesizing these compounds at high temperatures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Biochemistry & Molecular Biology
Boris P. Sobolev, Elena A. Sulyanova
Summary: The formation of materials with negative thermal expansion based on a phase transition-type mechanism in RF3-R'F-3 systems is predicted. Adjusting the reaction parameters can result in two-component materials with negative thermal expansion, which have better performance than known materials.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Alena Vishina, Daniel Hedlund, Vitalii Shtender, Erna K. Delczeg-Czirjak, Simon R. Larsen, Olga Yu Vekilova, Shuo Huang, Levente Vitos, Peter Svedlindh, Martin Sahlberg, Olle Eriksson, Heike C. Herper
Summary: A new class of rare-earth-free permanent magnets based on Co3Mn2Ge has been proposed, demonstrating promising magnetic properties and potential applications. The discovery was a result of combining first principles theory with experimental synthesis and characterisation, showing the critical role of disorder in Co and Ge atoms for improving magnetism.
Article
Chemistry, Physical
Satoru Enomoto, Sonju Kou, Taichi Abe, Yoshihiro Gohda
Summary: Computational examination of the phase equilibria in the Sm-Fe-Cu ternary system reveals the possibility of liquid-phase sintering producing nonmagnetic grain-boundary subphases in SmFe12-based magnets. The B2 Sm-Cu-Fe is identified as a potential nonmagnetic subphase, with attractive Cu-Fe interaction observed within the B2 sublattice. The equilibrium between the liquid phase of Sm-Cu and SmFe12 is also verified. The findings provide insights into the electron theory and suggest a feasible approach for liquid-phase sintering of SmFe12-based magnets.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Zhipeng Hou, Lingwei Li, Chen Liu, Xingsen Gao, Zhipan Ma, Guofu Zhou, Yong Peng, Mi Yan, Xi-xiang Zhang, Junming Liu
Summary: Skyrmionic spin configurations, including skyrmions and skyrmionic bubbles, have been studied in RE-based intermetallics compounds REMn2Ge2, which can host skyrmionic bubbles in a wide temperature range. Micromagnetic simulations show that the rotation of easy-magnetized axis plays a dominant role in the magnetic domain evolutions induced by temperature and magnetic field. This research has important implications for practical applications of skyrmionic spin configurations.
MATERIALS TODAY PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Quanzheng Tao, Justinas Palisaitis, Youbing Li, Qing Huang, Per O. A. Persson, Johanna Rosen
Summary: This paper investigates the incorporation of magnetic rare earth elements into the chemically ordered transition metal borides structure. The results show that Mo4/3RE2/3AlB2 materials can potentially be used as a versatile platform for new magnetic materials.
MATERIALS RESEARCH LETTERS
(2022)
Article
Metallurgy & Metallurgical Engineering
A. Ya. Travyanov, P. V. Petrovsky, V. V. Cheverikin, A. O. Lagutin, M. G. Khomutov, V. V. Luk'yanov
Summary: Joints of VT6 and VT20L titanium alloys were prepared by diffusion welding and hot isostatic pressing methods. Ti6Al4V alloy components were prepared using rolling and selective laser melting methods. Defects were found in the microstructure of specimens prepared by diffusion welding, while no defects were found in specimens prepared by hot isostatic pressing. The welded specimens exhibited high strength properties comparable to the VT20L base alloy material level.
Article
Thermodynamics
Alexandra Khvan, Alan Thomas Dinsdale, Qing Chen
Summary: This study discusses methods to define the Einstein temperature for metastable phases of elements and validates these methods using the Pb-Sn system.
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY
(2022)
Article
Chemistry, Physical
I. Fartushna, I. Bajenova, J. Shakirova, A. Khvan, V. Cheverikin, E. Zanaeva, A. Kondratiev
Summary: The phase equilibria in the Sm-Co, Sm-Fe, and Co-Fe-Sm systems were investigated, and the corresponding phase diagrams were constructed. The Sm-rich region in the Sm-Fe system was discovered, and the stability domains of intermetallic phases were defined. Three continuous solid solutions were found in the Co-Fe-Sm system. The phase diagram of the Sm-Co system was revised, revealing wide homogeneity regions for the SmCo5 and Sm2Co7 phases and alternative four-phase equilibria. The magnetic properties of samples containing the Sm-2(Co,Fe)(12) phase were measured and compared to literature values.
Article
Chemistry, Physical
A. K. Mohamed, V. V. Palacheva, V. V. Cheverikin, T. N. Vershinina, A. M. Balagurov, G. M. Muralikrishna, N. Esakkiraja, S. V. Divinski, G. Wilde, I. S. Golovin
Summary: This study has detected and discussed the significant differences between the properties of Fe-Ga alloys in their metastable and equilibrium states, as well as the discrepancies between existing Fe-Ga phase diagrams and the transition rates from the metastable to equilibrium state. The accurate knowledge of the equilibrium phase diagram, metastable phases, and the transition rates between different phase states towards equilibrium are necessary for both fundamental understanding and technological importance of these alloys, and further clarification is required. By utilizing a coherent set of complementary methods, including diffraction methods, scanning electron microscopy, and electron backscatter diffraction, the influence of alloy composition, annealing temperature, and annealing time on the metastable-to-equilibrium phase transitions in binary Fe-Ga has been studied. Several important changes to the low-temperature part of the binary Fe-Ga diagram near the Fe-rich corner and a new method based on interdiffusion couples for varying the structure and phase states of Fe-Ga alloys have been proposed.
Article
Chemistry, Physical
M. G. Mahmoud, Ahmed O. Mosleh, Andrey V. Pozdniakov, Waleed Khalifa, Mamdouh S. Mohamed
Summary: The present study investigates the effects of Samarium (Sm) addition on the performance of 6063 Aluminum alloy. The addition of Sm improves the solidification behavior, microstructure, and mechanical properties of the alloy. The addition of 0.1 wt% Sm significantly enhances the hardness and yield strength of the alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Ceramics
Irina A. Bajenova, Anton Guskov, Pavel G. Gagarin, Alexandra Khvan, Konstantin S. Gavrichev
Summary: In this study, the enthalpies of formation of compounds with pyrochlore structure of RE2Hf2O7 type were measured using high-temperature oxide melt solution calorimetry. The results were compared with literature data, and the relationship between the enthalpies of formation and the ionic radius of rare-earth element was analyzed. It was found that the enthalpy of formation becomes more positive with the increase in ionic radius, similar to what was observed for titanates and zirconates.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Ali Akbarpour, M. S. Parkhomenko, A. M. Khalil, V. V. Cheverikin, N. Yu. Tabachkova, E. N. Zanaeva, A. I. Bazlov
Summary: This work investigates the impact of thermomechanical treatment on the mechanical properties, structure, and crystallization of Zr65.5Ni16Cu8.5Al10 metallic glass alloy. The study reveals that thermomechanical treatment significantly alters the alloy's mechanical properties while preserving its amorphous structure through the development of chemically inhomogeneous regions within the amorphous matrix. Additionally, the alloy's initial crystallization is influenced by shear deformation, leading to a transition from one-stage to two-stage crystallization with increasing strain.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Ahmed O. Mosleh, Elena G. Kotova, Anton D. Kotov, Iosif S. Gershman, Alexander E. Mironov
Summary: Due to the engine's start/stop system and a sudden increase in speed or load, developing alloys with excellent tribological properties and high mechanical properties is crucial for engine bearings. This study introduces a novel approach using an artificial neural network (ANN) to accurately model and predict the mechanical properties of aluminum-based bearing alloys, optimizing their chemical composition for high mechanical properties. The study also highlights the impact of soft and more solid phases on the mechanical properties of these alloys.
Article
Thermodynamics
I. A. Bajenova, A. S. Ivanov, N. M. Konstantinova, I. A. Uspenskaya, A. V. Khvan, A. T. Dinsdale, A. Kondratiev
Summary: Third-generation Calphad models are used to study the thermodynamic properties of pure crystalline and liquid/amorphous silicon. A new approach is proposed to evaluate the parameters for the two-state liquid model for pure silicon. This new model representation allows for a better description of the experimental data for the isobaric heat capacity of the liquid phase.
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY
(2023)
Article
Physics, Multidisciplinary
Mikhail I. Razumovsky, Boris S. Bokstein, Alexey O. Rodin, Alexandra V. Khvan
Summary: The interdiffusion of elements in a diffusion pair of Ti and an equiatomic HEA TiZrHfNbTaMo was investigated in the temperature range of 1473-1673 K. The phase stability of the alloy was determined using the phase diagram obtained from Thermo-Calc 2021-B software. Ti-HEA diffusion pairs were obtained through low-temperature welding followed by diffusion annealing at temperatures of 1473, 1573, and 1673 K for different durations. The interdiffusion zone was analyzed using EPMA, and the diffusion parameters of HEA elements were obtained using Hall's method. Experimental results are discussed.
Article
Materials Science, Ceramics
Anatoly S. Arkhipin, Alexander Pisch, Georgii M. Zhomin, Semen V. Kuzovchikov, Alexandra V. Khvan, Natalia N. Smirnova, Alexey V. Markin, Nikita A. Kovalenko, Irina A. Uspenskaya
Summary: This study investigated the thermodynamic properties of a Ca12Al14O33 (C12A7) binary glass and the effects of titania additions (+5 and 7 wt%). Three different calorimetric techniques were used: low-temperature adiabatic, high-temperature drop solution, and transposed temperature drop calorimetry. The enthalpy of formation from oxides at 298.15 K and the enthalpy of dissolution of TiO2 (rut) at 1073.15 K were determined. The results showed that TiO2 additions had no influence on the heat capacity of C12A7, but caused a negative deviation of the enthalpy of formation from oxides.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2023)
Article
Materials Science, Multidisciplinary
Aleksandr Khovailo, Aidar Murtazin, Evgeniy Kolesnikov, Efim Argunov, Dmitry Karpenkov, Aleksandr Shubin, Irina Bazhenova, Aleksandra Khvan, Aleksei Bogach, E. M. Elsehly
Summary: It has been suggested that single-phase half-Heusler compounds can be obtained by introducing defects to adjust the valence electrons count to 18 in structurally unstable alloys with 19 valence electrons. This approach has now been extended to Fe-V-Al and Fe-Ti-Sn full-Heusler alloys. It was found that the non-stoichiometric Fe-V-Al exists as a single-phase compound, while the non-stoichiometric Fe-Ti-Sn is a multiphase compound. The crystal structure of the studied Fe-V-Al was found to be cubic, with a slightly larger lattice parameter compared to the stoichiometric Fe2VAl full-Heusler alloy. This finding opens up new possibilities for the design of previously unknown thermoelectric Heusler alloys.
Article
Chemistry, Physical
I. Bajenova, E. Gvozdeva, A. Khvan, V. Cheverikin
Summary: The phase stabilities of intermetallic phases and phase equilibria in the Cu-Sm system were evaluated using DTA, SEM/EPMA and XRD methods. Cu6Sm and Cu5Sm were found to have certain homogeneity ranges, and it was confirmed that CuSm forms through a peritectic reaction. The updated phase equilibria data led to a new version of the Cu-Sm phase diagram. The hardness of the Cu6Sm phase was measured to be 335 ± 29 HV.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Yury V. Gamin, Alexander V. Skugorev, Mukhamed M. Karashaev, Tatiana Y. Kin, Sergei P. Galkin, Abdullah Mahmoud Alhaj Ali, Vladimir V. Cheverikin
Summary: The article analyzes the microstructure evolution of Co-Cr-Mo alloy during isothermal forging. Isothermal forging can produce a high-quality microstructure for subsequent deformation processing. The required modes of ingot homogenization are determined through analysis and calculations. Isothermal forging in specific temperature and strain rate conditions allows obtaining a defect-free microstructure for further metal forming methods.
