Article
Materials Science, Multidisciplinary
Bo Yin, Jin Huang, Wei Xie, Jiale Wang, Shanshan Xu, Zhenhua Li
Summary: The addition of CaF2 during WAAM enhances the microstructure of titanium alloys, resulting in a high strength-ductility combination and improved mechanical properties.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Engineering, Manufacturing
Dylan Agius, Chris Wallbrink, Kyriakos Kourousis
Summary: The design freedom provided by Additive Manufacture (AM) technologies is driving innovation in new directions, but also creating challenges in material characterisation. This paper proposes a model that combines anisotropic yield function with nonlinear multicomponent kinematic hardening rule to accurately simulate the anisotropic behavior of materials like Ti-6Al-4V alloy. The model's performance was evaluated through simulations and showed good agreement with experimental data, demonstrating its efficiency in modeling cyclic stress-strain evolution in different build orientations.
ADDITIVE MANUFACTURING
(2021)
Article
Materials Science, Multidisciplinary
Yifei Luo, Yuehuang Xie, Zhen Zhang, Jiamiao Liang, Deliang Zhang
Summary: A Ti-6Al-4V alloy with a dual harmonic structure was successfully fabricated by controlling grain sizes and element contents. This structure helps reduce mechanical mismatch and enhances strength and ductility.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Mechanics
Xue Yang, Chenlin Liu, Yi Ding, Haodong Li, Yazhou Guo, Yulong Li
Summary: The paper investigates the dynamic plastic behavior of Ti-6Al-4V titanium alloy under complex loading conditions at high strain rates. By proposing a dynamic asymmetry yield criterion and loading surface, considering the coupling effects of strain rate and stress state, the reliability and accuracy of these models are validated. The study also reveals the non-uniformity in the initial yield surface and the expansion of loading surfaces under different stress states at high strain rates.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2023)
Article
Engineering, Chemical
Lei Pan, Menglin Wang, Jingling Hu, Pengbo Xue, Huaxin Guo, Lang Zhong, Xiaosa Yuan, Hanqiao Shi
Summary: The adhesive performance between Ti-6Al-4V alloy plates and PEEK can be improved by using sulfonated poly-ether-ether-ketone (SPEEK) as a modifier and pre-treatments such as anodizing and sandblasting. The successful loading of SPEEK on TC4 plates leads to a significant enhancement in interlaminar shear strength, and bonding mechanisms such as mechanical interlocking, molecular entanglement, hydrogen bonding, and enhanced van der Waals forces can be observed.
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
(2022)
Article
Nanoscience & Nanotechnology
Jeong-Rim Lee, Min-Su Lee, Si Mo Yeon, Dongseok Kang, Tea-Sung Jun
Summary: The study reveals that heat treatment increases ductility and decreases yield strength in AM Ti-6Al-4V ELI material, while samples loaded along the perpendicular direction exhibit higher ductility and strain hardening rate.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Automation & Control Systems
Xuming Zha, Zhi Yuan, Hao Qin, Linqing Xi, Bicheng Guo, Tao Zhang, Feng Jiang
Summary: The ultrasonic impact-strengthening technology effectively improves the fatigue resistance of key components in aerospace manufacturing, such as titanium alloys, by combining static and dynamic impact loads. A test platform was developed to investigate the influence mechanisms of static and cyclic dynamic loads in the ultrasonic impact-strengthening process. The results show a coupling effect in the force values, with the force increasing by more than 55% compared to the sum of static and dynamic loads. The deformation strain rate of Ti-6Al-4V during the process and the material surface hardening mechanism were also analyzed.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Materials Science, Coatings & Films
Yichen Meng, Matteo Villa, Kristian Dahl, Bo Wang, Michel Drouet, Jean-Baptiste Dubois, Marcel A. J. Somers, Thomas L. Christiansen
Summary: This study investigated the surface hardening and heat treatment response of Ti-6Al-4V grades G5 and G23 under different temperature and gaseous conditions. Various surface treatments were applied, resulting in different hardness values and structure formations. The diversity of treatments in this work represents the potential of gaseous and plasma-based thermochemical methods for surface engineering of titanium alloys.
SURFACE & COATINGS TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Miguel Ruiz de Sotto, Veronique Doquet, Patrice Longere, Jessica Papasidero
Summary: In this study, an extensive experimental campaign and numerical simulations were conducted to investigate the ductile fracture behavior of Ti-6Al-4V titanium alloy. The results showed that ductility of the material exhibited anisotropic characteristics depending on the stress state and strain rate, with different behavior observed in tension and compression. The fracture strain was found to decrease with increasing absolute value of the triaxiality, reaching a maximum close to zero, while no clear correlation with the Lode parameter was identified.
INTERNATIONAL JOURNAL OF DAMAGE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Jonathan Cappola, Jean-Charles Stinville, Marie-Agathe Charpagne, Patrick G. Callahan, McLean P. Echlin, Tresa M. Pollock, Adam Pilchak, Matthew Kasemer
Summary: The equiaxed microstructure of Ti-6Al-4V alloy contains alpha-phase grains of varying orientations. The presence of microtextured regions can adversely affect the mechanical properties of the alloy, particularly quasi-static and fatigue properties. Studies have shown that orientation spread within microtextured regions facilitates strain localization, and the intensity of microtexture in neighboring regions further influences the extent of strain localization.
Article
Materials Science, Multidisciplinary
Vladimir V. Skripnyak, Vladimir A. Skripnyak
Summary: By conducting tensile tests and Digital Image Correlation analysis, the mechanical behavior of the Ti-6Al-4V alloy at different strain rates was studied. It was found that at high strain rates, the alloy exhibited localized shear bands and the ultimate strain to fracture in the strain localization zone tended to increase with the strain rate, while showing a tendency towards embrittlement at high stress triaxialities.
Article
Chemistry, Physical
Xuefeng Zhou, Yulin Li, Ziru Han, Zilin Liu, Kaiwen Liu, Yiyou Tu, Feng Fang, Jianqing Jiang
Summary: A novel pathway for improving the work hardening capacity of Ti-6Al-4V alloy via simple solution in the virgin lower alpha + beta regime is proposed. Elemental partitioning and depletion of beta-stabilizers occur between alpha and beta phases as the solution temperature rises, resulting in the creation of metastable beta phases that transform into alpha '' martensite during mechanical straining. The stress-induced beta(m) -> alpha'' martensite transformation induces three-staged strain hardening and the desired transformation-induced plasticity effect, providing the alloy with a high strain hardening rate and good combinations of strength and ductility.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Metallurgy & Metallurgical Engineering
Peng Lin, Xian-zheng Xi, Wen-kai Zhao, Rui-hong Yang, Fei Lin, Xiao-lei Cui, Gang Liu
Summary: Ti-6Al-4V and Ti-22Al-25Nb were diffusion bonded at 950 degrees C and 15 MPa, forming a complex microstructure at the interface. The tensile strength of the joint is similar to that of the base alloy, and the fracture surfaces consist of two main regions with different shapes of defects.
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
(2021)
Article
Engineering, Mechanical
Jianfeng Zhao, Xinlei Pan, Jian Li, Zhiyong Huang, Qianhua Kan, Guozheng Kang, Liucheng Zhou, Xu Zhang
Summary: Systematic characterization of microstructure, mechanical testing and constitutive modeling were conducted to investigate the effects of laser shock peening (LSP) treatment on the tensile properties of Ti-6Al-4 V alloy. The study revealed that LSP treatment resulted in grain refinement and introduction of compressive residual stress, leading to changes in the material's elastic-plastic behavior. The established deformation mechanism-based model showed that surface grain refinement enhanced initial yielding and strain hardening, while residual stress had a weakening effect on initial yielding but little influence on strain hardening behavior.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Mechanical
Hao Li, Si-Rui Xie, Shi-Hong Zhang, Shuai-Feng Chen, Hong-Wu Song, Yong Xu, Artur I. Pokrovsky, Boris B. Khina
Summary: By utilizing Impact Hydro-bending (IHB), the spring-back of Ti-6Al-4V sheet at room temperature can be significantly reduced. However, existing analytical models for spring-back prediction fail to accurately account for the complex space-time deformation history, making it difficult to predict the spring-back behavior under IHB. This paper proposes a theoretical model that considers both the effects of space-time deformation history and strain rate, allowing for a more accurate prediction and understanding of the spring-back reduction mechanism.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Baoqi Guo, Wenqi Mao, Yan Chong, Akinobu Shibata, Stefanus Harjo, Wu Gong, Huicong Chen, John J. Jonas, Nobuhiro Tsuji
Summary: The dynamic transformation from alpha to beta phase in a zirconium alloy during hot compression was revealed by in-situ neutron diffraction. The transformation was accompanied by diffusion of Sn from beta to alpha phase, resulting in changes in lattice parameters and the microstructure of alpha grains. The occurrence of the dynamic transformation was attributed to an increase in the Gibbs free energy of the alpha phase relative to the beta phase, making the alpha phase thermodynamically more unstable than the beta phase.
Article
Materials Science, Multidisciplinary
Reza Gholizadeh, Shuhei Yoshida, Yu Bai, Shu Kurokawa, Akinobu Shibata, Nobuhiro Tsuji
Summary: In this study, the deformation behavior of the CoCrFeMnNi alloy under ultra-high strains at various temperatures was investigated. It was found that deformation twinning was extensively activated at moderate to high strains and at elevated temperatures above 600 degrees C. The alloy showed excellent deformability at low temperatures, but embrittlement occurred at intermediate temperatures. This research provides insights into the microstructure evolution and mechanical response of the Cantor alloy under shear deformation at a wide range of strains and temperatures.
Article
Materials Science, Multidisciplinary
Wu Gong, Stefanus Harjo, Yo Tomota, Satoshi Morooka, Takuro Kawasaki, Akinobu Shibata, Nobuhiro Tsuji
Summary: The martensitic transformation is accompanied by the generation of internal stresses at both microscale and macroscale during cooling. Previous studies using X-ray or neutron diffraction have reported inconsistent results due to the influence of factors such as solute elements and crystal defects on the measured lattice parameter.
Article
Nanoscience & Nanotechnology
Avala Lavakumar, Myeong-heom Park, Reza Gholizadeh, Ranjit Kumar Ray, Mitsuhiro Murayama, Nobuhiro Tsuji
Summary: Low-carbon multi-phased steels with transformation induced plasticity (TRIP) effect have attracted significant attention for automotive applications due to their superior mechanical balance between strength and ductility. However, the complex microstructural evolutions during thermo-mechanical processing and the influence of constituent phases on mechanical properties have not been fully understood. In this study, the formation process of multi-phased microstructures in a low alloy steel during intercritical annealing and subsequent partitioning heat-treatment were systematically investigated. The phase fractions of ferrite, martensite, and retained austenite were found to change significantly with increasing holding time at lower temperature. Newly formed ferrite was observed to transform from austenite through massive or bainitic transformation, resulting in different types of ferrite in the final microstructures. The presence of retained austenite was attributed to interstitial carbon diffusion, leading to improved tensile elongation and TRIP effect during deformation. The best strength-ductility balance was achieved with the shortest heat-treatment at lower temperature.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
Avala Lavakumar, Myeong-heom Park, Sukyoung Hwang, Hiroki Adachi, Masugu Sato, Ranjit Kumar, Mitsuhiro Murayama, Nobuhiro Tsuji
Summary: Deformation-induced martensitic transformation is a crucial phenomenon for achieving both high strength and large ductility in low alloy multi-phase steels. The transformation induced plasticity (TRIP) effect, which involves the phase transformation from austenite to martensite during deformation, can significantly enhance the strain hardening ability. The mechanical stability of austenite against martensitic transformation is influenced by the surrounding phases, but the details are still unclear.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Yan Chong, Jangho Yi, Guanyu Deng, Nobuhiro Tsuji
Summary: The aging behavior of Ti-1.0 wt pct Fe alloy was studied in this research, focusing on microstructural modifications within the beta grains. At lower aging temperatures, omega(ath) precipitates gradually decreased and were replaced by alpha(s) precipitates. At higher aging temperatures, alpha(s) precipitates increased in size while their volume fraction decreased, indicating a partial alpha to beta reverse phase transformation. The presence of omega(ath) promoted a homogeneous precipitation behavior of alpha(s) precipitates, leading to the formation of plate-shaped alpha(s) precipitates with multiple crystallographic variants.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Wu Gong, Takuro Kawasaki, Ruixiao Zheng, Tsuyoshi Mayama, Binxuan Sun, Kazuya Aizawa, Stefanus Harjo, Nobuhiro Tsuji
Summary: The deformation behavior of a commercial AZ31 magnesium alloy was studied during uniaxial compression at 21 K and 298 K using in-situ neutron diffraction. Decreasing the deformation temperature led to a slight increase in yield stress, but a remarkable enhancement in both the fracture stress and fracture strain. The low temperature sensitivity of the {10 (1) over bar2} extension twinning resulted in the slight increase in yield stress. At 21K, basal slip was suppressed, while extension twinning was promoted, leading to a higher twin volume fraction. The suppression of {10 (1) over bar1}-{10 (1) over bar2} double twinning in the late stage of deformation was considered to be the reason for the delayed fracture at 21 K.
SCRIPTA MATERIALIA
(2023)
Article
Nanoscience & Nanotechnology
Yan Chong, Reza Gholizadeh, Kaichi Yamamoto, Nobuhiro Tsuji
Summary: The coarse lamellar microstructure of as-cast alpha+beta titanium alloys can be effectively refined by boron additions, which has mainly been attributed to the precipitation of TiB whiskers that pin the growth of prior beta grains. We report an alternative mechanism of colony refinement in Ti-6Al-4V alloy containing trace amounts of boron solutes (0.02 wt.%). Using atom probe tomography, it is discovered for the first time that boron solutes segregate at the alpha/beta phase boundaries, due to its negligible solubilities in both alpha and beta phases. These segregated boron solutes at the alpha/beta phase boundaries restrict an easy growth of grain boundary alpha, and in turn promote the nucleation of more grain boundary alpha variants that serve as nucleation sites of alpha colonies. Hence, the colony size can be substantially refined without the formation of TiB whiskers that could be harmful to the ductility of the material.
SCRIPTA MATERIALIA
(2023)
Article
Nanoscience & Nanotechnology
Avala Lavakumar, Shuhei Yoshida, Jesada Punyafu, Shiro Ihara, Yan Chong, Hikaru Saito, Nobuhiro Tsuji, Mitsuhiro Murayama
Summary: The study focuses on the influence of grain size and temperature on the mechanical properties of equiatomic FeCoNi alloy. Different grain sizes ranging from ultra-fine to coarse were achieved by high-pressure torsion and annealing. The results show that the tensile yield strength is affected by temperature and grain size, and the grain boundary strength remains constant while the friction stress increases at lower temperature. At cryogenic temperature, the presence of nano twinning contributes to the enhancement of strength and ductility in addition to dislocation slip.
SCRIPTA MATERIALIA
(2023)
Article
Nanoscience & Nanotechnology
Elis Sjogren-Levin, Wolfgang Pantleon, Aylin Ahadi, Zoltan Hegedus, Ulrich Lienert, Nobuhiro Tsuji, Kei Ameyama, Dmytro Orlov
Summary: In situ X-ray diffraction was used to study the tensile deformation behavior of HS nickel, which consists of a continuous network of fine grains and islands of coarse grains. A separation algorithm was developed to analyze the X-ray diffraction signals from coarse and fine grains separately. Line profile analysis was used to examine the evolution of local stresses and microstrains in different grain fractions. The study identified several stages during yielding and the onset of plastic deformation in HS nickel, and found that the plastic deformation of coarse grains is constrained by the network of fine grains.
SCRIPTA MATERIALIA
(2023)
Article
Materials Science, Ceramics
Kejia Kang, Bo Yu, Guanyu Deng, Pei Wang, Jian Yin, Hongbo Zhang, Guoqiang Luo, Hao Song
Summary: This study fabricated a copper impregnated carbon/carbon composite for a novel sliding collector material, and investigated the effects of counterpart materials on friction and wear behaviors, comparing the results with carbon contact strip used in high-speed railway. The study found that the Cu-C/C composite exhibited superior mechanical strength, electrical conductivity, wear resistance, and friction performance compared to the pure carbon strip.
CERAMICS INTERNATIONAL
(2023)
Article
Nanoscience & Nanotechnology
Qian He, Shuhei Yoshida, Nobuhiro Tsuji
Summary: This study reports the characteristic strengthening mechanisms of HfNbTaTi, HfNbTiZr, HfNbTi, HfTaTi, and NbTiZr equi-atomic refractory medium entropy alloys (RMEAs). The alloys were processed to obtain microstructures with varying grain sizes and their mechanical properties were evaluated. The low elastic modulus of the RMEAs was found to be the reason for their small slopes of the Hall-Petch relationships and weak grain refinement strengthening. Moreover, the high friction stresses of the RMEAs were attributed to the interaction between severe lattice distortion and elastic field of edge dislocations.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
J. Zamora, T. Bautista, N. S. Portillo-Velez, A. Reyes-Montero, H. Pfeiffer, F. Sanchez-Ochoa, H. A. Lara-Garcia
Summary: Experimental and DFT studies were conducted on the structural, magnetic, and optical properties of RFeO3 perovskites. The perovskites exhibited an orthorhombic crystal structure and weak ferromagnetic behavior. They were confirmed to be semiconductors with a bandgap of approximately 2.1 eV.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xianxiang Lv, Jing Jin, Weiguang Yang
Summary: By depositing TiN and TiO2 surface layers on AlSi films, the electrochemical performance of silicon-based anodes can be significantly improved, suppressing volume expansion and promoting the formation of a stable SEI layer.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Sharafat Ali, Haider Ali, Syedul Hasnain Bakhtiar, Sajjad Ali, Muhammad Zahid, Ahmed Ismail, Pir Muhammad Ismail, Amir Zada, Imran Khan, Huahai Shen, Rizwan Ullah, Habib Khan, Mohamed Bououdina, Xiaoqiang Wu, Fazal Raziq, Liang Qiao
Summary: The construction and optimization of redox-heterojunctions using a bifunctional phosphate as an electron-bridge demonstrated significant improvements in photo catalytic activity, including enhanced dispersion, reduced interfacial migration resistance, and increased abundance of active-sites.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ren-Ni Luan, Na Xu, Chao-Ran Li, Zhi-Jie Zhang, Yu-Sheng Zhang, Jun Nan, Shu-Tao Wang, Yong-Ming Chai, Bin Dong
Summary: Extensive research has revealed that oxygen evolution reaction (OER) in alkaline conditions involves dynamic surface restructuring. The development and design of sulfide/oxide pre-catalysts can reasonably adjust the composition and structure after surface reconstruction, which is crucial for OER. This study utilized a simple two-step hydrothermal method to achieve in situ S leaching and doping, inducing the composition change and structure reconstruction of CoFe oxides. The transformed FeOOH and CoOOH exhibited excellent OER activity and could be easily mass-produced using low-cost iron based materials and simple methods.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jun'an Lai, Daofu Wu, Peng He, Kang An, Yijia Wang, Peng Feng, WeiWei Chen, Zixian Wang, Linfeng Guo, Xiaosheng Tang
Summary: Zero-dimensional organic-inorganic metal halides (OMHs) are gaining attention in the fabrication of light-emitting diodes due to their broad emission band and high photoluminescence quantum yield. This work synthesized a zero-dimensional organic tetraphenylphosphonium bismuth chloride (TBC) that showed efficient blue light emission, with the emission mechanism attributed to the transition of Bi3+ ions. White light-emitting diodes (WLEDs) were fabricated using TBC, along with green-emitting and red-emitting single crystals, achieving single-component white emissions. These findings demonstrate the different emission mechanism of ns2 ions-based OMHs and highlight the potential of bismuth-based OMHs in WLEDs applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xuewei Liang, Yunhai Su, Taisen Yang, Zhiyong Dai, Yingdi Wang, Xingping Yong
Summary: The revolutionary design concept of high-entropy alloys has brought new opportunities and challenges to the development of advanced metal materials. In this work, AlCrCuFe2NiTix high-entropy flux cored wires were prepared by combining the design idea of a high-entropy alloy with the characteristics of flux cored wire. AlCr-CuFe2NiTix high-entropy surfacing alloys were prepared using gas metal arc welding technology. The wear properties of the alloys were analyzed, and the phase composition, microstructure, strengthening mechanism, and wear mechanism were discussed. The results show that the alloys exhibit a dendritic microstructure with BCC/B2 + FCC phases. Increasing Ti content leads to the precipitation of Laves phase. The alloys show improved microhardness and wear resistance due to the precipitation of coherent B2 and Laves phases. However, excessive Ti addition results in the increase of Laves phase and reduced wear resistance of the alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
M. Vadivel, M. Senthil Pandian, P. Ramasamy, Qiang Jing, Bo Liu
Summary: This work presents the enhanced photocatalytic and electrochemical performance of g-C3N4 assisted PAA on CoFe2O4 ternary nanocomposites. The incorporation of PAA and g-C3N4 improves the separation efficiency of photogenerated charge carriers, resulting in superior photocatalytic degradation and high specific capacitance values.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Vibhu T. Sivanandan, Ramany Revathy, Arun S. Prasad
Summary: In this study, pure and doped cobalt ferrite nanoparticles were prepared using the sol-gel auto-combustion method with the aid of lemon juice as eco-fuel. The crystal structure, lattice parameter, crystallite size, microstrain, optical parameters, and room temperature magnetic properties of the samples were analyzed. The effect of doping on the magnetic properties was also investigated.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qing Guo, Bowen Zhang, Benzhe Sun, Yang Qi
Summary: This study prepared ZnO films with various nonpolar preferred orientations using conventional chemical bath deposition method and characterized their growth process and mechanism. It was found that the type and concentration of nitrate could control the preferred orientation and surface roughness of ZnO films. Additionally, ZnO films with different preferred orientations exhibited different optical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Chong Zhang, Yan Liu, Zhaoyan Wang, Hang Yang
Summary: In this study, six bimetallic FeCo particles were synthesized via the hydrothermal method at different Fe:Co ratios. The Fe:Co ratio not only modulates the composition of the particles but also influences their structure and magnetic properties. The FeCo alloys showed a transformation from an Fe-based structure to a Co-based structure with increasing Co content. The Fe:Co ratio of 1:1 and 3:1 resulted in particles with the highest and lowest saturation magnetization, respectively.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jianning Zhang, Jing Li, Yiren Wang, Xiaodong Mao, Yong Jiang
Summary: We conducted a study on the formation of ultra-fine Y-Ti-Ta-O nano-oxides in Ta+B micro-alloyed 13CrWTi-ODS alloys using electron microscopy and first-principles calculations. The Y-Ti-Ta-O nano-oxides were found to be mainly Y2(Ti,Ta)2O7, with an average size of 7 nm and a number density of 6.8 x 1023 m-3. Excess boron was found to enhance the adhesion of some low-sigma grain boundaries but weaken the Fe/Y2Ti2O7 interface, while excess tantalum enhanced the Fe/Y2Ti2O7 interface but caused serious degradation of grain boundaries.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Yirong Fang, Pei Cheng, Hang Yuan, Hao Zhao, Lishu Zhang
Summary: A new composite system of nitrogen-doped reduced graphene oxide and black phosphorus quantum dots has been developed for tumor therapy, showing improved electrochemical properties and stability. The system generates hydrogen peroxide and hydroxyl radical to effectively kill tumor cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xiufang Qin, Yuanli Ma, Hui Zhang, Ting Zhang, Fang Wang, Xiaohong Xu
Summary: The structure and magnetism of cobalt ferrites after Mn2+-Tb3+ co-doping were studied. Co-doped samples exhibited cubic spinel structure and spherical shape of ferrite nanoparticles. The redistribution of Co2+ and Fe3+ ions between octahedral and tetrahedral sites was observed due to Mn2+-Tb3+ co-doping. The coercivity and magnetization saturation of co-doped samples were significantly improved, leading to a maximum energy product that is 190% higher than that of the un-doped sample.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ho Yeon Lee, Wonjong Yu, Yoon Ho Lee
Summary: Recently, there has been an increasing interest in developing ultra-fine nanostructured electrodes with extensive reaction areas to enhance the performance and low-temperature operation of solid oxide fuel cells. The use of a refined approach involving co-sputtering metal alloys and oxide targets has demonstrated the feasibility of nano-columnar structures in perovskite-based electrodes, expanding the temperature range of thin film electrodes. This study systematically examines the effects of chamber pressure control in the co-sputtering process and identifies the intricate relationship between sputtering pressure and film structure. By fine-tuning the columnar growth in the electrode, significant improvements in performance and thermo-mechanical properties were achieved, resulting in high-performance all-sputtered solid oxide fuel cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qianyun Bai, Xiaoxiao Yan, Da Liu, Kang Xiang, Xin Tu, Yanhui Guo, Renbing Wu
Summary: This study proposes a simple method to develop a non-precious transition metal-based electrocatalyst with high catalytic activity and robustness for the hydrogen evolution reaction. The as-synthesized electrode exhibits a low overpotential and high current density, indicating its potential in energy conversion.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)