Article
Chemistry, Physical
Nengbin Hua, Wenjie Wang, Qianting Wang, Youxiong Ye, Sihan Lin, Lei Zhang, Qiaohang Guo, Jamieson Brechtl, Peter K. Liaw
Summary: The study on TixZrNbTaMo high entropy alloys revealed excellent properties in hardness, corrosion resistance, and wear resistance, with improvement in wear resistance in phosphate buffer saline solution as the titanium content decreases. The Ti0.5ZrNbTaMo alloy showed the highest corrosive wear resistance among the four HEAs due to its superior mechanical properties and chemical stability.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Ceramics
Yichen Wang, Duo Yu, Jie Yin, Buhao Zhang, Hangfeng Zhang, Xuejian Liu, Yulong An, Michael J. Reece, Zhengren Huang
Summary: The ablation behavior of HEC-0 and the effect of SiC content on ablation resistance were investigated. The results showed that the complex oxide layer played a positive role in reducing the linear ablation rate of HEC-0. The addition of SiC significantly improved the ablation resistance of the composites.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Dalibor Preisler, Tomas Krajanak, Milos Janecek, Jiri Kozlik, Josef Strasky, Michal Brazda, Jan Dzugan
Summary: Bulk Nb-Ta-Ti-Zr refractory complex concentrated alloy (RCCA) was prepared using the additive manufacturing method of directed energy deposition (DED) from an equiatomic mixture of elemental powders. Scanning velocity was varied to investigate the effect of different heat inputs, and it was found that decreasing scanning velocity effectively reduced the number of undissolved Nb/Ta particles in the microstructure. Preheating the platform to 500 degrees C during deposition resulted in the best microstructure homogeneity. Homogenization annealing at 1400 degrees C/24 h was performed, but complete Ta particles dissolution was not achieved. Optimization of deposition parameters is crucial for achieving reasonable microstructure homogeneity in RCCA produced from elemental powders, as homogenization annealing cannot eliminate heterogeneities at the scale of powder particles size.
Article
Materials Science, Multidisciplinary
Yuuka Iijima, Takeshi Nagase, Aira Matsugaki, Pan Wang, Kei Ameyama, Takayoshi Nakano
Summary: By applying empirical alloy parameters and thermodynamic calculations, new noble nonequiatomic Ti-Zr-Hf-Nb-Ta-Mo high-entropy alloys for metallic biomaterials were designed. The Mo equivalent and valence electron concentration parameters were found to be useful for alloy design, including BCC structure formation in bio medium-entropy alloys and BioHEAs.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Ceramics
Yang Liu, Wei-Ming Guo, Liang Xu, Shi-Kuan Sun, Hua-Tay Lin
Summary: The high sintering temperature can damage the morphology and properties of SiCw in HEC-SiCw composites, which affects the toughening mechanisms. This study aims to maximize the toughening effects of SiCw by preparing (Ti, Zr, Nb, Ta, Mo)C-SiCw composites with cobalt as additives at low temperature (1600 degrees C). Results showed that the fracture toughness of the (Ti, Zr, Nb, Ta, Mo)C bulk reinforced with 20 vol% SiCw and 5 vol% Co was 7.2 MPa·m1/2, higher than that of (Ti, Zr, Nb, Ta, Mo)C bulk sintered with only 5 vol% Co (3.4 MPa·m1/2) and HEC-20 vol% SiCw composite sintered at 2000 degrees C (4.3 MPa·m1/2). Introduction of damage-free SiCw significantly increased the fracture toughness of HEC-SiCw composites.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2023)
Article
Chemistry, Physical
V. A. Aranda, I. A. Figueroa, V Amigo, R. Gonzalez-Ojeda, O. Lozada, A. L. Vidilli, L. B. Otani, G. Gonzalez
Summary: In this work, the mechanical properties of a Ti-Nb-Ta-Zr alloy were improved by adjusting the composition with phase equilibria simulation and adding Mo. X-ray spectroscopy characterization showed that Ta and Nb segregated in the BCC1 phase, while Zr and Ti segregated in the BCC2 phase. The mechanical properties were related to the chemical differences between the BCC1 and BCC2 lattice parameters induced by the Mo addition.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Ceramics
Zanlin Cheng, Wenyu Lu, Lei Chen, Meng Li, Xuxu Han, Mei Li, Yujin Wang, Chengyu Zhang
Summary: The compressive creep properties of (Ti-Zr-Nb-Ta-Mo)C high-entropy ceramics were studied and found to exhibit higher creep resistance and steady-state creep rates compared to TaC. The creep mechanisms of the HEC involve dislocation motion, grain boundary sliding, and atom diffusion. Additionally, the atom diffusion is less active in (Ti-Zr-Nb-Ta-Mo)C due to sluggish lattice diffusion.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Metallurgy & Metallurgical Engineering
A. A. Korenev, A. G. Illarionov
Summary: The elastic properties of quenched biocompatible titanium-based alloys were calculated and compared with literature and experimental data. The study showed that an increase in the molybdenum equivalent led to an increase in the shear and Young moduli and a decrease in the Poisson coefficient, indicating the stability of the solid alloy beta-solution.
PHYSICS OF METALS AND METALLOGRAPHY
(2022)
Article
Chemistry, Physical
Ka-Kin Wong, Hsueh-Chuan Hsu, Shih-Ching Wu, Wen-Fu Ho
Summary: Three nonequiatomic Ti-rich Ti-Zr-Nb-Mo medium-entropy alloys were developed for biomedical applications, exhibiting high yield strength, low elastic moduli, and excellent resilience. The distortion effect caused by alloying atomic radius difference contributed to the superior yield strengths of the alloys. Increasing Ti content can prevent segregation issues and reduce the elastic modulus.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Ceramics
Annamaria Naughton-Duszova, David Medved, Lenka Dakova, Alexandra Kovalcikova, Peter Svec, Peter Tatarko, Hakan Unsal, Pavol Hvizdos, Pavol Sajgalik, Jan Dusza
Summary: The wear characteristics of a fine-grained dual-phase high-entropy (Ti0.14Zr0.2Nb0.2Hf0.2Ta0.26)C + (Ti0.38Zr0.18Nb0.22Hf0.115Ta0.105)B-2 were studied using the ball-on-flat technique in air. The material had high density, small grain size, and high hardness. The friction coefficient increased with sliding distance, and the specific wear rate decreased with increasing sliding distance. The dominant wear mechanisms were oxidation-driven tribo-chemical reaction and tribo-layer formation in boride grains, as well as mechanical wear in carbide grains.
ADVANCES IN APPLIED CERAMICS
(2023)
Article
Materials Science, Multidisciplinary
Weijie Weng, Arne Biesiekierski, Jixing Lin, Sertan Ozan, Yuncang Li, Cuie Wen
Summary: This study investigated the newly designed beta-type Ti-Nb-Zr-Mo (TNZM) alloys for orthopedic applications, and found that TNZM1, TNZM2, and TNZM3 exhibited higher elastic admissible strain, high hardness, good ductility, and cytocompatibility.
APPLIED MATERIALS TODAY
(2021)
Article
Biochemistry & Molecular Biology
Yuliya Y. Khrunyk, Sabrina Ehnert, Stella Grib, Anatoly G. Illarionov, Stepan Stepanov, Artemiy A. Popov, Maxim A. Ryzhkov, Sergey Belikov, Zeqian Xu, Frank Rupp, Andreas K. Nuessler
Summary: A novel low elastic modulus Ti-based alloy was synthesized and analyzed, showing lower elastic modulus and good in vitro biocompatibility compared to Ti-6Al-4V. O-2 plasma treatment significantly increased the hydrophilicity and in vitro biocompatibility of the alloy, while not inducing inflammatory responses. These results suggest that the TNZTS alloy may be a potential alternative to Ti-6Al-4V.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Minhyung Ahn, Yongmo Park, Seung Hwan Lee, Sieun Chae, Jihang Lee, John T. Heron, Emmanouil Kioupakis, Wei D. Lu, Jamie D. Phillips
Summary: High-entropy-oxide-based memristors composed of Zr, Hf, Nb, Ta, Mo, and W oxides demonstrate uniform distribution of vacancies and low stochastic behavior in resistive switching, showing promise for neuromorphic applications. These memristors exhibit forming-free operation, low device and cycle variability, gradual conductance modulation, 6-bit operation, and long retention.
ADVANCED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Inorganic & Nuclear
Pavlina Solcova, Matej Niznansky, Jiri Schulz, Petr Brazda, Petra Ecorchard, Monika Vilemova, Vaclav Tyrpekl
Summary: High-entropy ceramics, represented by metal carbides of Ti, Zr, Hf, Ta, and Nb, are materials with great potential and wide applications. A chemical route to synthesize high-entropy carbide powder at a lower temperature has been developed, allowing for ideal mixing of precursors on a molecular level without the need for milling and blending steps. The resulting phase-pure high-entropy carbide was characterized through solid-state analysis.
INORGANIC CHEMISTRY
(2021)
Article
Materials Science, Ceramics
Si-Chun Luo, Wei-Ming Guo, Kevin Plucknett, Hua-Tay Lin
Summary: This study successfully prepared (Ti,Zr,Nb,Ta,Mo)C ceramics with high hardness and high toughness using a liquid-phase sintering process combined with a Co-based liquid-phase extrusion strategy. The densification temperature was significantly reduced to 1350 degrees C, and part of the Co-based liquid-phase was removed during the sintering, resulting in a lower Co content in the ceramic.
JOURNAL OF ADVANCED CERAMICS
(2022)
Article
Chemistry, Multidisciplinary
H. W. Chang, H. Y. Wang, Y. Lee, Y. M. Guo, W. C. Chang, C. C. Shaw
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2020)
Article
Nanoscience & Nanotechnology
H. W. Chang, Y. H. Chien, F. T. Yuan, Y. R. Lai, C. R. Wang, Lance Horng, W. C. Chang
Article
Chemistry, Analytical
Yeong-Maw Hwang, Cheng-Tang Pan, Ying-Xu Lu, Sheng-Rui Jian, Huang-Wei Chang, Jenh-Yih Juang
Article
Chemistry, Physical
H. W. Chang, Y. M. Guo, S. H. Liao, W. C. Chang, C. C. Shaw
JOURNAL OF ALLOYS AND COMPOUNDS
(2020)
Article
Engineering, Multidisciplinary
H. C. Fan, Fu-Te Yuan, H. W. Chang, Chi-Yang Shen
Summary: An optical method has been proposed to monitor the order transformation of FePt thin films in real-time, with the onset temperature determined accurately by measuring surface reflection amplitude. The experimentally measured kinetic ordering temperatures for different compositions of FePt thin films are in good agreement with published DSC data, confirming the effectiveness of the optical method in tracking order transformation.
JOURNAL OF THE CHINESE INSTITUTE OF ENGINEERS
(2021)
Article
Nanoscience & Nanotechnology
H. W. Chang, G. T. Lin, Y. J. Wong, W. M. Huang, W. C. Chang
Summary: Significant enhancement in coercivity for hot deformed NdFeB magnets is achieved by doping R80Al20 (R= La, Ce, Dy, Tb) alloy powders. Microstructure analysis shows that Ce or La tends to distribute at grain boundary, while Dy or Tb and Al are located at grain boundary and surface. Magnetic isolation due to R-rich phase containing Nd, Ce or La, Al at the grain boundary contributes to coercivity enhancement, while strengthening magnetic anisotropy field of 2:14:1 phase due to Tb or Dy, and slight Al substitutions gives rise to significant coercivity enhancement.
Article
Nanoscience & Nanotechnology
Y. J. Wong, W. C. Hsu, H. W. Chang, Y. Lee, W. C. Chang, C. H. Chiu, C. C. Mo
Summary: Enhancement of coercivity in sintered NdFeB magnets through grain boundary diffusion (GBD) with Tb70Cu30 powders prepared by different milling methods was compared. Results showed that powders prepared by low-energy ball milling (LEBM) provided a wider contact area, leading to higher diffusion efficiency and coercivity increment.
Article
Chemistry, Multidisciplinary
Da-Hua Wei, Tei-Kai Lin, Yuan-Chang Liang, Huang-Wei Chang
Summary: Monodispersed FePt core and FePt-Au core-shell nanoparticles were chemically synthesized with controllable surface-functional properties. The size of the nanoparticles could be tuned by the initial concentration of gold acetate, and FePt-Au NPs showed a red shift in surface plasmon resonance compared to pure Au NPs. Surface modification using mercaptoacetic acid gave the NPs hydrophilic properties and potential applications in biomedical engineering research.
FRONTIERS IN CHEMISTRY
(2021)
Article
Materials Science, Multidisciplinary
Ting-Kai Lin, Huang-Wei Chang, Wan-Chi Chou, Chang-Ren Wang, Da-Hua Wei, Chi-Shun Tu, Pin-Yi Chen
Summary: In this work, we used pulsed laser deposition (PLD) with a Nd:YAG laser to fabricate Bi1-xGdxFeO3 (BGFO) films on glass substrates. The study found that with increasing Gd content, there is a gradual decrease in crystallite size and surface roughness in the BGFO films, and the magnetic properties are significantly enhanced due to Gd substitution.
Article
Physics, Applied
H. W. Chang, F. T. Yuan, D. Y. Lin, D. H. Tseng, W. C. Chang, Y. S. Chen, J. G. Lin
Summary: Large in-plane magnetic uniaxial anisotropy was achieved in Fe60Co20B20 thin films prepared by rotational sputtering, exhibiting outstanding thermal stability up to 350°C. These stress-induced anisotropy films were used as free layers in synthetic spin valves, showing a linear resistance change against external field and reduced coercivity, providing a simple synthesis route to induce magnetic anisotropy for spintronic device design.
APPLIED PHYSICS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Y. J. Wong, H. W. Chang, Y. Lee, W. C. Chang, C. H. Chiu, C. C. Mo
Summary: This study demonstrates the modification of magnetic properties and enhancement of coercivity of NdFeB sintered magnets using dual-alloy (DA) sintering and grain boundary diffusion (GBD) treatment. Addition of CeAl powders increases the coercivity, while incorporating TbCu powders through GBD further enhances the coercivity and achieves different levels of NdFeB magnets.
IEEE TRANSACTIONS ON MAGNETICS
(2022)
Article
Chemistry, Physical
H. W. Chang, S. U. Jen, Y. Y. Shen, D. H. Tseng
Summary: The saturation magnetostriction of sputter-prepared Fe71Co10Ga19 films on Si(100) substrates is mainly influenced by the amount of m-D0(3) phase and can be controlled by adjusting sputtering parameters. The thickness dependence of magnetostriction shows an increase in lambda s as thickness decreases in the range of 200 nm to 50 nm, while a decrease is observed in the range of 50 nm to 30 nm.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
H. W. Chang, S. U. Jen, Y. H. Liao, D. H. Tseng, H. Y. Hsieh, W. C. Chang, C. H. Chiu, J. Cifre, D. G. Chubov, I. S. Golovin
Summary: Enhancement of magneto-mechanical properties in Fe80Al20 alloys by doping Tb has been demonstrated, showing improved magnetostriction and sensitivity. The increased magnetostriction with Tb content is related to the degree of (110) texture. However, higher Tb content may lead to degradation of magneto-mechanical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
H. W. Chang, Y. M. Guo, Y. H. Fang, W. C. Chang, C. C. Shaw
Summary: The magnetic properties of melt spun LaCo5-based ribbons can be significantly improved by modifying the phases and refining the grains, resulting in reduced coercivity and enhanced squareness of the demagnetization curve. Substitution of elements M (M = Ti, Zr, Hf) for Co and R (R = Ce, Pr, Nd, Sm, Y) for La in the compositions also contributes to the enhancement of magnetic properties.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Materials Science, Coatings & Films
T. K. Lin, H. W. Chang, C. R. Wang, D. H. Wei, C. S. Tu, P. Y. Chen
Summary: This study investigated the phase constitutions, ferroelectric, magnetic, and nanomechanical characteristics of BiFeO3 films with Dy substitution. The results showed that the BDFO films exhibited desired ferroelectric and ferromagnetic properties, and the hardness of the films was controlled mainly by the impeded propagation of dislocation by grain boundary. The findings suggest that the radius and magnetic moment of the Dy3+ ions play a critical role in the structural evolution and enhanced properties of the BDFO films.
SURFACE & COATINGS TECHNOLOGY
(2022)