Article
Materials Science, Ceramics
Katy S. Gerace, Michael T. Lanagan, John C. Mauro
Summary: Understanding the mechanisms contributing to dielectric properties of glasses is critical for designing new compositions for microwave frequency applications. In this work, dielectric permittivity was measured for a series of niobiosilicate glasses with varying compositions. The calculations of polarizability and experimental results reveal that SiO2 polarizability depends on the chemistry and connectivity of the glass, which has important implications for designing glass compositions for microwave frequency applications.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Crystallography
Boyang Chen, Qingyu Zhang, Dongke Sun, Zhijun Wang
Summary: The growth of columnar dendrites during rapid directional solidification of IN718 alloy in the presence of shear flows is simulated using a CA-LB model. The study reveals that the shear flow rate and cooling rate have significant effects on the evolution of primary dendrite arm spacing (PDAS).
JOURNAL OF CRYSTAL GROWTH
(2022)
Article
Materials Science, Multidisciplinary
Fuqiang Zhang, Yi Song, Xianfei Ding, Jianping He, Yongfeng Liang, Junpin Lin
Summary: A novel phenomenon called dendrite splitting was observed in as-cast TiAl alloys, showing microstructural and crystallographic characteristics similar to twinned dendrites. The formation of this phenomenon is related to the attachment behavior of atoms at the liquid-solid interface. This study provides new details on the solidification process of TiAl alloys.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
Anderson Thadeu Nunes, Guilherme Lisboa de Gouveia, Jose Eduardo Spinelli
Summary: This study investigates the influence of cooling rates on the phase morphology and tensile properties of ternary Al-Mg-Sc alloys. It was found that higher amounts of Mg result in higher solidification rates and the formation of a variety of microstructures. Among the alloys studied, the Al-5 wt% Mg-Sc alloy exhibited superior tensile strength due to the predominance of cells and thinner primary dendrites trunks forming its microstructure.
MATERIALS CHARACTERIZATION
(2023)
Article
Chemistry, Physical
Zhuoxin Li, Lingshan Ou, Yipeng Wang, Hong Li, Mariusz Bober, Jacek Senkara, Yu Zhang
Summary: Aluminum alloy 7075 was welded using a digital welding machine with different arc modes. The results showed that CMT-based welding had lower solidification cracking susceptibility, slower cooling rate, and reduced micro-segregation of alpha-Al dendrites compared to MIG welding. The T-(f(Al))(1/2) curve analysis demonstrated that CMT welding enhanced the bridging of adjacent dendrites, decreasing the tendency for solidification cracking.
Article
Chemistry, Physical
Piotr Mikolajczak
Summary: Natural convection exists in all liquid alloys, while forced convection can be used to improve material properties. By studying the solidification in simple cylindrical samples using a rotating magnetic field with a low cooling rate and low temperature gradient, the effect of forced convection was investigated. The research focused on the composition of Al-Si-Fe alloys and the resulting modifications in structure and phases. The findings suggested that stirring led to the formation of rosette structures, altering dendrite spacing and specific surface area, and modifying certain phases. Additionally, the melt flow caused a modification in iron-rich phases and their redistribution within the alloy sample.
Article
Nanoscience & Nanotechnology
Guilherme Lisboa de Gouveia, Amauri Garcia, Jose Eduardo Spinelli
Summary: Magnesium-silicon alloys were studied for their microstructural characteristics and tensile properties, with variations in solidification cooling rate and silicon content. The increase in silicon content led to a reduction in strength and ductility, likely due to the increase in Mg2Si particles.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Green & Sustainable Science & Technology
Cassio Silva, Andre Barros, Adilson Vitor Rodrigues, Rafael Kakitani, Thiago Soares, Amauri Garcia, Noe Cheung
Summary: The addition of V into Al-based alloys can reduce the fraction of beta-AlFeSi particles, leading to improved tensile properties under faster cooling conditions during solidification. However, for moderate and slow cooling regimes, the V-containing alloy exhibits less favorable mechanical behavior due to the formation of larger beta-AlFeSi particles. Quantitative relationships for predicting tensile properties from microstructural parameters using multiple linear regression analysis are proposed.
Article
Electrochemistry
F. Layachi, M. Y. Debili
Summary: The addition of ternary elements to the binary alloy Al-40 wt.% Nb can enhance its corrosion resistance. The heat-treated alloy #3 and as-cast binary alloy #4 exhibit excellent electrochemical performance.
JOURNAL OF APPLIED ELECTROCHEMISTRY
(2022)
Article
Nanoscience & Nanotechnology
Ming-Xue Zhang, Hong Ning, Cheng Wang, Kai Guan, Xuan Wang, Zhi-Gang Li, Hui-Yuan Wang
Summary: This study investigates the addition of 0.08 wt% Zr to Al-1.0Mg-1.2Si (6022) alloy and its effects on the solidification process of twin-roll casting (TRC). The addition of Zr promotes the transition from columnar to equiaxed structure and refines the solidification microstructure of the alloy. It also mitigates the macro-segregation during the solidification process of the TRC strip. The incorporation of Zr leads to the formation of (Al, Si)3Zr phases, which act as heterogeneous nucleation sites for α-Al dendrites and π-AlFeMgSi phase. The refinement of the microstructure reduces the secondary dendrite arm spacing and increases the partition coefficients of Mg and Si elements, resulting in the alleviation of central macrosegregation. The mechanical properties of the alloy strips, including fracture elongation and yield strength, are optimized with Zr addition. This work provides a strategy for effectively controlling macro-segregation and producing high-performance alloy strips through the TRC process.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Jiacheng Niu, Zhiqiang Fu, Weiping Chen, Liangyan Hao, Wei Xiong, Tiwen Lu, Haiming Wen
Summary: This study investigates the effect of minor elements Co and Ti on Al-Cr-Fe-Ni high-entropy alloys. It is found that the combination of Co and Ti has a synergistic effect on the alloys, enhancing both yield strength and ultimate tensile strength. However, the addition of Ti renders the alloy brittle.
MATERIALS CHARACTERIZATION
(2023)
Review
Materials Science, Multidisciplinary
D. J. M. King, A. J. Knowles, D. Bowden, M. R. Wenman, S. Capp, M. Gorley, J. Shimwell, L. Packer, M. R. Gilbert, A. Harte
Summary: This review discusses the potential of current Zr alloys and advanced Zr alloys to meet the requirements of structural materials in fusion reactors. While current commercial Zr alloys can be used in water-cooled breeder blanket designs, they fail to meet the high temperature strength and thermal creep requirements for breeder blankets operating at higher temperatures. Higher order Zr alloys show promise in achieving the necessary high temperature strength, ductility, and low thermal neutron cross-section, but there is limited data and uncertainty regarding their structural performance and microstructural stability at these temperatures.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
Jaskaran Singh Saini, John P. Miska, Fuqiong Lei, Nicholas AuYeung, Donghua Xu
Summary: Metallic glasses, especially Hafnium based MGs, have superior properties to conventional crystalline metals/alloys, with HBMGs having the additional advantage of high density. However, their glass-forming ability is limited. Our discovery of two HBMGs with a critical casting diameter significantly higher than the current record allows for the production of bigger products and easier manufacturing/processing.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Manufacturing
Sumit Bahl, Alex Plotkowski, Thomas R. Watkins, Richard A. Michi, Benjamin Stump, Donovan N. Leonard, Jonathan D. Poplawsky, Ryan Dehoff, Amit Shyam
Summary: Additive manufacturing (AM) allows for the printing of structures with site-specific properties. In this study, a simple approach utilizing eutectic solidification characteristics is demonstrated to achieve site-specific properties in an Al-Cu-Ce-Zr alloy using laser powder bed fusion AM. The yield strength of the alloy can be tuned by adjusting the laser scan speed and hatch spacing, with faster speeds resulting in finer eutectic spacing and higher strength. The relationship between scan speed, eutectic spacing, and strength is successfully applied to print a complex pattern of site-specific hardness in the alloy, showcasing the potential of using AM for creating site-specific properties and anisotropy in alloys.
ADDITIVE MANUFACTURING
(2023)
Article
Nanoscience & Nanotechnology
Sheng Zeng, Guoqiang You, Fanjin Yao, Jingchuan Luo, Xin Tong
Summary: Research on the diffusion bonding of similar joints of zirconium (Zr) alloys is limited compared to that on dissimilar joints. This study demonstrated successful vacuum diffusion bonding of Zr-2.5Nb (Zr705) alloy with a Cu interlayer and analyzed the microstructure and mechanical properties of the joints. The tensile strength of the joints increased with bonding temperature, reaching a maximum of 603 MPa at 960 degrees C, while the elongation first increased and then decreased with increasing temperature, reaching 54% at 940 degrees C.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Huijun Yang, Yaqin Tan, Junwei Qiao, Jeffrey A. Hawk, Yong Zhang, Michael Gao, Peter K. Liaw
Summary: The phase stability, microstructural evolution, and mechanical properties of Al0.6CoCrFeNi high-entropy alloy (HEA) under different thermo-mechanical treatments were systematically investigated. The study observed the presence of face center cubic (FCC) matrix, B2 and minor Body Center Cubic (BCC) phases in the as-cast state, and noted the evolution of B2 precipitate morphology from needle-like to droplet-shaped after annealing at different temperatures. The research successfully analyzed the resulting yield stress of this FCC/B2 duplex-phase HEA, attributing it to contributions from solid solution strengthening, precipitate strengthening, grain boundary hardening, and dislocation hardening.
Article
Materials Science, Multidisciplinary
Fangfei Liu, Peter K. Liaw, Yong Zhang
Summary: This paper systematically reviews the mechanical behaviors and properties of BCC-structured HEAs, analyzes the effect of alloying on their mechanical properties, discusses the effects of HEA preparation and compositional regulation on corrosion resistance, and explores the application of high-throughput techniques in the field of HEAs.
Article
Materials Science, Multidisciplinary
Weiran Zhang, Yasong Li, Peter K. Liaw, Yong Zhang
Summary: This study utilizes empirical parameters to design depleted uranium high-entropy alloys (DUHEAs). The empirical criteria have been proven to be an effective means in development. UNb0.5Zr0.5Mo0.5 and UNb0.5Zr0.5Ti0.2Mo0.2 HEAs with outstanding mechanical properties have been successfully created.
Article
Materials Science, Multidisciplinary
Rongbin Li, Tian Huang, Jing Zhang, Chunxia Jiang, Yong Zhang, Peter K. Liaw
Summary: An experimental method for preparing high-entropy thin films with gradient changes of alloying elements by magnetron sputtering co-deposition was proposed in this study to evaluate the effect of alloying element composition changes on the properties of non-equal molar ratio high-entropy alloys. The (TiVCr)x-(TaW)1-x binary system thin films were deposited and their surface morphology, element composition, roughness, and phase structure were studied. The results showed that the films with x = 0.51 exhibited the best mechanical properties, hardness, and wear resistance, as well as improved radiation resistance.
Article
Materials Science, Multidisciplinary
Yasong Li, Peter K. Liaw, Yong Zhang
Summary: This study investigates the influence of Cr, Mo, and Si elements on the phase structures and properties of low-density Al-Zr-Ti-Nb high-entropy alloys, providing theoretical and scientific support for the development of advanced low-density alloys.
Article
Materials Science, Multidisciplinary
Tingting Li, Sizhe Diao, Pingping Liu, Yong Zhang, Qian Zhan
Summary: An equiatomic low-activated FeCrV ternary alloy with excellent strength-ductility synergy properties was prepared by mechanical alloying and spark plasma sintering. The alloy exhibited high temperature resistance and showed remarkable irradiation tolerance compared with pure Fe.
PROGRESS IN NATURAL SCIENCE-MATERIALS INTERNATIONAL
(2022)
Article
Nanoscience & Nanotechnology
Lin Deng, Jin-ru Luo, Jian Tu, Rong Hu, Ning Guo, Wen-yu Zeng, Chang-hao Wang, Pei He, Yong Zhang
Summary: As a candidate material for fuel cladding in fission reactors, the mechanical properties of ODS-F/M steel were improved by incorporating ultra-high number density of Y2O3 oxide nanoparticles through the addition of Y2O3 during HIP and optimizing microstructure and properties through hot rolling deformation. The addition of Y2O3 resulted in a bimodal ferrite structure and reticular M23C6 carbides distribution. Following hot rolling, grain size and M23C6 carbides were refined significantly while Y2O3 particle size remained unchanged. This resulted in an excellent combination of strength (1474 MPa) and ductility (13%) in ODS steel prepared by HIP with Y2O3 addition and hot rolling.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
Shichao Zhou, Chunduo Dai, Huaxing Hou, Yiping Lu, Peter K. Liaw, Yong Zhang
Summary: A bionic bamboo fiber heterogeneous microstructure was created in an ultrafine-grained eutectic high-entropy alloy, AlCoCrFeNi2.1, through multi-pass cold-drawing and subsequent annealing. The bionic microstructure consists of a hard-B2 fiber embedded in a soft-face-centered-cubic (FCC) matrix, resulting in excellent strength and ductility synergy.
SCRIPTA MATERIALIA
(2023)
Review
Materials Science, Multidisciplinary
Kaixuan Cui, Yong Zhang
Summary: This paper discusses the preparation process, microstructure, hardness, wear resistance, and corrosion resistance of high-entropy alloy films, and analyzes the influence of factors such as nitridation, sputtering power, substrate temperature, and substrate bias on the phase structure of alloy films. High-entropy alloy films can be prepared using various processes. They tend to form a solid solution and amorphous state, and their hardness is much higher than that of traditional films. Some high-entropy alloy films have better corrosion resistance than stainless steel due to the corrosion-resistant elements and amorphous structure. High-entropy alloy films have promising development prospects in wear-resistant coatings, corrosion protection, diffusion barriers, and photothermal conversion coatings.
Article
Materials Science, Multidisciplinary
Kuan Gao, Yuexin Chu, Weihua Zhou, Yong Tian, Yong Zhang, Yi Li
Summary: This study systematically investigates the phase inversion phenomenon in a high-Al-content B2 refractory high-entropy alloy (RHEA) through thermo-mechanical treatment. The grains of the single B2 phase transform inversely to the BCC+B2 microstructure with a dispersion of spherical B2 precipitates in the BCC grains. The phase inversion process enhances the tensile ductility of the RHEA while maintaining its high specific strength.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Yangyong Zhao, Yuanyuan Bai, Tie Li, Yong Zhang, Eiichi Sato
Summary: Cu-Sn shape-memory microwires were fabricated by a glass-coated melt spinning method. The effects of Sn content on the microstructure and mechanical properties of microwires were investigated. It was found that a high cooling rate in the method greatly improved the mechanical properties and superelasticity of the microwires.
Article
Materials Science, Multidisciplinary
Ruixuan Li, Guihong Geng, Yong Zhang
Summary: High-entropy alloys (HEAs) have gained significant attention for their unique composition design and excellent properties, and the concept of entropy regulation has been widely used to develop performance-oriented alloys. Lightweight high-entropy alloys (LHEAs) are important lightweight materials that exhibit special properties due to high alloying elements and high mixing entropy, including high specific strength, high specific hardness, and excellent corrosion resistance. However, there are still unresolved questions regarding phase formation rules and comprehensive performance in specific service environments. This paper reviews the composition design, phase formation rules, mechanical properties, physical properties, and chemical properties of typical LHEAs, highlighting the challenges and future development directions.
MRS COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Dan Liu, Xi Jin, Huijun Yang, Junwei Qiao, Yong Zhang
Summary: The temperature sensitivity of cobalt-free high-entropy alloys Fe45Mn15Cr15Ni25 and Fe35Mn15Cr15Ni25Al10 was investigated. The addition of aluminum improves the mechanical properties and thermal stability of the alloys, but exacerbates the serration behavior.
Article
Materials Science, Multidisciplinary
Ruixuan Li, Baixue Bian, Gerhard Wilde, Yong Zhang, Sergiy V. Divinski
Summary: The tracer self-diffusion of Co in a compositionally complex AlCoCrFeNiTi0.2 alloy was measured using the radiotracer technique. The analysis of the complex multi-phase microstructure allowed for the determination of volume diffusion coefficients and grain boundary diffusion coefficients.
Review
Materials Science, Multidisciplinary
Xuehui Yan, Yu Zou, Yong Zhang
Summary: High-entropy alloys (HEAs) are emerging materials that can be designed with different structures and physical characteristics through chemical disorder. Over the past two decades, significant efforts have been made to explore the unique and useful properties of HEAs, such as overcoming the strength-ductility trade-off, outstanding thermal stability, and excellent low temperature plasticity. This article reviews the key research topics of HEAs, including performance advantages, composition design, and fabrication processes. Methods for synthesizing, fabricating, and processing HEAs are also discussed, along with current challenges and future opportunities for performance breakthroughs.
