Article
Chemistry, Physical
Tian Hong Zhou, Hui-Dong Qian, Jung Tae Lim, Han-Kuk Jeon, Chul-Jin Choi, Young-Rae Cho, Jihoon Park
Summary: We have successfully fabricated high-purity high-density Sm(Fe0.8Co0.2)(12-2x)TixVx (0.6 ≤ x ≤ 1.0) bulk magnets through the bulking of amorphous powder and subsequent annealing process. The addition of Cu-Ga additive enhanced the grain boundary structure and improved the magnetic properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Y. . L. Huang, Q. Rao, Q. Feng, Z. J. Wu, Y. F. Yao, Y. H. Hou, W. Li, J. M. Luo
Summary: Grain boundary diffusion (GBD) is used to improve the coercivity of Nd-Fe-B magnets without reducing the remanence and maximum magnetic energy product. Dy30Cu70 alloy is used as the diffusion source to enhance the coercivity. The diffusion of Dy and Cu leads to the formation of (Nd, Dy)2Fe14B shell in the matrix phase, inhibiting the nucleation of reversed magnetic domain and increasing the magnetic isolation effect between matrix phases. The optimization of the intergranular phase and the formation of (Dy, Nd)2Fe14B shell contribute to the significant improvement of coercivity. Additionally, the diffusion of DyCu alloy improves thermal stability and corrosion resistance.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
V. V. Palacheva, A. G. Mochugovskiy, D. G. Chubov, A. N. Koshmin, V. V. Cheverikin, J. Cifre
Summary: The current research focuses on the microstructural analysis, damping, and magnetostrictive behavior of Fe-12Al and Fe-21Al alloys doped with Tb after various mechanical and heat treatments. It was found that thermomechanical treatment enhances magnetostriction in both alloys, with the maximum observed after hot rolling followed by annealing at 900 degrees C and air cooling. Tb addition also increases the low temperature IF background and magnetostriction of Fe-21Al-Tb alloy.
Article
Chemistry, Physical
Yongsheng Liu, Jiaying Jin, Xinhua Wang, Mi Yan
Summary: Through the methods of grain boundary restructuring and grain boundary diffusion process, the introduction of (Pr, Nd)H-x into La-Ce-40 sintered magnet successfully increased the coercivity of the magnet. The grain boundary diffusion process can maintain a higher remanence compared to grain boundary restructuring.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Rongrong Ma, Rui Wang, Mei Ge, Zhiwen Guo, Guohui Yang, Junfeng Zhang
Summary: This paper investigates the influence of grain boundaries on the thermodynamic stabilities, electronic, and magnetic properties of 2D magnetic material CrI3. It is found that most zigzag type grain boundaries are more stable and exhibit lower formation energy compared to armchair ones. Additionally, grain boundaries can increase magnetic moments and Curie temperatures simultaneously. Based on the stable grain boundary structure, more stable CrI3-CrI2 lateral heterostructure and graphdiyne-like hybrid system are proposed, which show tunable electronic and magnetic properties for potential applications.
APPLIED SURFACE SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Yang Zhao, Haibo Feng, Anhua Li, Wei Li
Summary: By using TbHx powders for grain boundary diffusion processing, it is possible to improve the coercivity and remanence of N50 sintered Nd-Fe-B magnets. The study investigates the effects of processing temperature and time on the microstructure and magnetic properties of the magnets, highlighting the increase in coercivity and remanence achieved at specific conditions.
Article
Materials Science, Multidisciplinary
Qingzheng Jiang, Guo Yang, Chuanjia Zhao, Qingfang Huang, Weiguo Wei, Huixia Li, Qiang Ma, Zhenchen Zhong
Summary: By using grain boundary diffusion method with PrCuGa as the diffusion source, the magnetic properties of commercial Nd-La-Y-Fe-B magnets were successfully improved. After annealing treatment, the Hcj and (BH)max of the magnets increased significantly. This improvement is mainly attributed to the partial replacement of La by Pr, forming (Pr,Nd,La, Y)2Fe14B with higher intrinsic properties.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Leonie Gomell, Moritz Roscher, Hanna Bishara, Eric A. Jaegle, Christina Scheu, Baptiste Gault
Summary: Laser surface remelting of Fe2VAl results in the growth of elongated grains nearly epitaxially within the melt pool, with low-angle grain boundaries exhibiting segregation of vanadium, carbon, and nitrogen. The study suggests that grain boundary engineering can potentially be used to manipulate thermoelectric properties, as indicated by a smaller increase in electrical resistivity at low-angle grain boundaries compared to high-angle grain boundaries in cast samples.
SCRIPTA MATERIALIA
(2021)
Article
Materials Science, Multidisciplinary
Di Qiu, Pengyang Zhao, Yunzhi Wang
Summary: This study presents a phase-field simulation framework to accurately predict the characteristics of defect structures, such as stresses and energies. By simulating the stress field and structure prediction of defects, the framework avoids stress singularities and reveals the energy minimization process and interactions between crystalline defects.
MATERIALS & DESIGN
(2021)
Review
Materials Science, Multidisciplinary
Gregory S. Rohrer, Ian Chesser, Amanda R. Krause, S. Kiana Naghibzadeh, Zipeng Xu, Kaushik Dayal, Elizabeth A. Holm
Summary: Grain boundaries in polycrystalline materials migrate to reduce excess energy. Previous studies found that the migration rates of boundaries in bicrystals are insufficient to explain boundary migration in polycrystals. In this review, we discuss the atomistic mechanisms of grain boundary migration based on simulations and microscopy observations. We also explore the continuum scale understanding of grain boundary migration through simulations and observations. It is concluded that detailed comparisons between experiments and atomistic simulations in polycrystals are necessary to better understand the migration mechanisms, and that current simulations of grain growth are inadequate in reproducing experimental observations.
ANNUAL REVIEW OF MATERIALS RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Wenfeng Zhang, Yang Meng, Jianfeng Wang, Shaokang Guan, Tao Zhang
Summary: This paper investigates a new heat treatment method to inhibit the brittleness caused by annealing in Fe-based amorphous alloys. By using a self-designed continuous rapid annealing equipment, the amorphous precursors were rapidly annealed at 773K for 0.3 s, resulting in the formation of a-Fe phase with a size of 2 to 5 nm. The ribbon sample exhibits high saturation magnetization and low coercivity, as well as good bending ductility.
Article
Materials Science, Ceramics
F. A. Huaman-Mamani, C. Jimenez-Holgado, M. Jimenez-Melendo
Summary: Three-phase alumina/YAG/YSZ composites were fabricated by a solid-state reaction route, resulting in dense bulk composites with fine equiaxed grains. Compressive mechanical tests at high temperatures showed a transition from brittle to ductile behavior, with grain boundary sliding as the main deformation mechanism in the ductile regime.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Nanoscience & Nanotechnology
Xiang Liu, Mei Wu, Ke Qu, Peng Gao, Wenbo Mi
Summary: In this study, artificial grain boundaries were introduced in Fe3O4 films to manipulate the magnetic and transport properties of materials. It was found that the in-plane rotation of Fe3O4 lattice on bicrystal substrates altered the magnetization processes, with Fe3O4 bicrystal films with larger tilt angles exhibiting strong in-plane magnetic anisotropy.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Hao Chen, Weiqiang Liu, Zizhen Guo, Tianyuan Yang, Yuan Qin, Yuqing Li, Hongguo Zhang, Ming Yue
Summary: In this study, Pr-Fe-B was used to prepare LaCe-based MMP sintered magnets, which achieved improved magnetic properties by increasing the anisotropy field and optimizing the composition and structure of the grain boundary phase.
Article
Chemistry, Physical
Tengfei Wu, Shuai Cao, Mingpeng Kou, Yuheng Xie, Guangfei Ding, Shuai Guo, Bo Zheng, Renjie Chen, Minglong Zhong, Aru Yan
Summary: This study investigated the influence of rare earths and non-rare earth metallic elements on the diffusion effect of low Tb content alloy diffusion sources in commercial NdFeB sintered magnets. The results showed that the coercivity of the magnets significantly increased with moderate amounts of metallic elements, but deteriorated when the total amounts of metallic elements reached a certain level. Microstructure analyses revealed that the excellent diffusion effects contributed to the coercivity enhancements, with deeper Tb diffusion depths and distinguishable core-shell structures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
