Article
Chemistry, Physical
Qinghai Pan, Xinbao Zhao, Yuan Cheng, Quanzhao Yue, Yuefeng Gu, Hongbin Bei, Ze Zhang
Summary: In this study, the microstructure evolution of the fourth-generation nickel-based single crystal superalloys with different Co additions is investigated at three thermal exposure temperatures. The effects of Co content and aging temperatures on the coarsening rate of the gamma ' phase are analyzed based on LSW theory and TIDC theory. The results reveal that the diffusion coefficient of solute is accelerated, but the gamma/gamma ' interfacial energy decreases with the addition of Co, thus changing the coarsening rate. The alleviation of thermodynamic equilibrium solubility difference and element segregation at the gamma/gamma ' interface with Co increase suppresses the TCP phase after long-time thermal exposure, providing guidance for the economical design of nickel-based single crystal superalloys.
Article
Nanoscience & Nanotechnology
Shunyong Zhang, Jianfeng Zhao, Yanxiang Liang, Jicheng Li, Xicheng Huang
Summary: The effect of phase coarsening on crack propagation characteristics and fracture toughness in Ni-based superalloys is investigated. It is found that the fracture toughness of the alloys is considerably degraded with phase coarsening and exhibits anisotropic characteristics.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2024)
Article
Chemistry, Physical
Rasim Eris, M. Vedat Akdeniz, Amdulla O. Mekhrabov
Summary: The atomic size of alloying elements is the primary factor affecting the strengthening of Ni-based superalloys. This study investigates the influence of Hf element addition and its co-additions with Mo(W) elements on the microstructural and mechanical properties of model Ni80Al15Hf5 and Ni80Al15Hf2.5Mo(W)2.5 superalloys. It is concluded that replacing a portion of Hf addition with Mo(W) can reduce the participation tendency of Hf and Mo(W) elements, and the co-addition of Hf and W leads to better mechanical strength.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Wenchao Yang, Huajing Zong, Chen Yang, Pengfei Qu, Haijun Su, Yin Dong, Jun Zhang, Lin Liu
Summary: The effect of Fe addition on y' precipitates in Ni-20Co-xFe-12Cr-7.5Al-7.5Ti-1.5 W single crystal superalloys was systematically studied. The results showed that higher Fe content resulted in a lower volume fraction and changed morphology of y' precipitates. Additionally, the alloy with Fe addition exhibited a higher coarsening rate of y' precipitates during thermal exposure.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
Yinfei Ju, Huiyu Wang, Peng Sang, Zan Zhang, Kaiyue Li, Hongli Long, Yongsheng Li
Summary: In this study, the evolution kinetics of y'-Ni3Al phase in Ni-15Al-2Mo alloy under creep stress was investigated using phase-field modeling method, which revealed the directional diffusion of elements between y/y' phases. It was found that the increase of Al concentration and the decrease of Mo concentration both promoted the directional connection of y' phase. The difference of chemical potential and elastic potential between y phase and y' phase drove the elements directional diffusion between y/y' phases, with Mo playing a leading role.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Cuiping Wang, Jianping Le, Keying Chen, Chen Yang, Jinxin Yu, Yihui Guo, Haojun Zhuo, Jinbin Zhang, Jiajia Han, Xingjun Liu
Summary: This paper presents an innovative investigation on gamma/gamma'-strengthened multi-component Co-Ni-Ti-V-based superalloys, which has led to the successful development of high-strength Co-Ni-Ti-based superalloys. The study provides valuable insights and support for the advancement of Co-Ti-based superalloys, offering improved high-temperature performance with high gamma' solvus temperature, low density, and low lattice mismatch.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Yuan Cheng, Xinbao Zhao, Wanshun Xia, Quanzhao Yue, Yuefeng Gu, Xiao Wei, Hongbin Bei, Yingying Dang, Ze Zhang
Summary: The microstructural stability of Ni-based single crystal superalloys with various Mo content during thermal exposure at 900 degrees C was investigated. The coarsening of y' precipitates and the formation of TCP phases were discussed. The study found that increasing Mo content enhanced the partitioning behavior of alloying elements, increased lattice misfit and interfacial stress, and slowed down the diffusion process. However, Mo addition significantly promoted the precipitation of TCP phases, consuming solution strengthener elements and limiting creep life.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Nanoscience & Nanotechnology
Yu Li, Zhenjun Hong, Binggang Liu, Xiaoshuai Jia
Summary: The microstructure evolution and mechanical properties were investigated in a multi-precipitation Ni-Co base superalloy system with different chemical compositions. The interaction of multi-precipitates and its influence on the creep behavior were studied, showing that the 2# Ni-Co alloy exhibits significantly higher creep strain rate and an advanced accelerating creep stage compared to the 1# Ni-Co alloy during creep process.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Satyapriya Gupta, Curt A. Bronkhorst
Summary: A dislocation density based crystal plasticity model is developed to capture the micromechanical behavior of gamma' strengthening nickel-based superalloys. The model incorporates multiple strengthening mechanisms and models the interaction between gamma and gamma' phases. The model also considers back stress induced by dislocation interactions and APB shearing as dominant deformation mechanisms.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Materials Science, Multidisciplinary
Sigeng Zhou, Naicheng Sheng, Shijie Sun, Shigang Fan, Jinjiang Yu, Guichen Hou, Jinguo Li, Yizhou Zhou, Xiaofeng Sun
Summary: The evolution of gamma' phase and gamma/gamma' eutectic during short-time heat treatment of the Ni-based superalloy with high W content, K416B are investigated. High temperature Differential Scanning Calorimetry (DSC) is employed to design the heat treatment experiments and the precipitate temperature of secondary gamma' is found in the cooling curve. A standard coarsening model is used to determine the coarsening rate constant of gamma' precipitate. Based on this, a novel method is proposed to predict the globularization time of gamma phase in gamma/gamma' eutectic during heat treatment.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Hao Yu, Zhaotian Wang, Yongquan Ning, Shuo Huang, Qiaomu Liu
Summary: Columnar evolution and DRX mechanisms of a Ni-Co-W type superalloy with typical columnar grains during hot deformation were investigated. It was found that new dynamic recrystallization (DRX) grains gradually replaced the columnar grains and nucleation occurred at the original columnar boundaries or folding positions. Different DRX mechanisms were identified, including discontinuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX), depending on the deformation temperature and strain level. The findings provide insights into the microstructure evolution of Ni-based superalloys and are beneficial for optimizing their properties for turbine disc manufacturing.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Xianjue Ye, Dingmao Zhou, Biaobiao Yang, Fenglin Wang, Jiantao Liu, Yunping Li
Summary: The influence of Co on the coarsening behavior of the gamma' phase in Ni-base superalloy was investigated. It was found that the coarsening rates of the gamma' phase decreased gradually with increasing Co content, which was attributed to the lower interfacial energy between gamma and gamma' in high Co content alloy. Additionally, the morphology of the gamma' phase after thermal exposure showed a cubic shape in low Co content alloy and a spherical shape in high Co content alloy. The evolution of the gamma' phase morphology during thermal exposure was found to be highly related to the gamma/gamma' misfit.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
K. G. Wang
Summary: The kinetics of phase coarsening in a dense binary, two-phase system were theoretically studied and existing relations were recovered and generalized. Equations for particle size distribution and coarsening were rigorously derived. An interesting finding is that the scaling exponent, m, for the kinetics of phase coarsening at ultra high volume fractions takes values in the range 2 < m < 3, depending on the precise volume fraction of the dispersed phase, when varied over the narrow range 0.9 < V-V < 1. The particle size distributions derived in this study depend on volume fractions, which is different from Wagner's particle size distribution for interface-reaction-controlled phase coarsening. The current work substantiates that the kinetics of phase coarsening at ultra high volume fractions exhibits a blend of both interface-reaction-controlled and volume diffusion-controlled phase coarsening.
Article
Materials Science, Multidisciplinary
M. Cottura, B. Appolaire, A. Finel, Y. Le Bouar
Summary: Microstructure evolutions in Ni-base superalloys under [110] creep loading were investigated using 3D and 2D phase field simulations. It was found that minor misorientations of the tensile axis lead to rafting, while loading along a perfectly aligned [110] direction results in a microstructure composed of rod-like precipitates. The direction of the mechanical load significantly affects the evolution of microstructure and macroscopic creep behavior.
Article
Nanoscience & Nanotechnology
Jiudong Sun, Jinlin Li, Hongyao Yu, Zhenhua Wang, Qing Wang, Chuang Dong
Summary: The present work focuses on the design of low-cost Ni-base superalloys with a high volume fraction of gamma' precipitates. The study finds that certain alloys exhibit high microstructural stability and slow coarsening rate, and a moderate lattice misfit contributes to the stability of the microstructure. Additionally, these alloys demonstrate excellent mechanical properties, with high yield strength and good microstructural stability.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
A. Cervellon, S. Hemery, P. Kuernsteiner, B. Gault, P. Kontis, J. Cormier
Article
Nanoscience & Nanotechnology
Satoshi Utada, Jeremy Rame, Sarah Hamadi, Joel Delautre, Patrick Villechaise, Jonathan Cormier
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2020)
Editorial Material
Materials Science, Multidisciplinary
Tresa M. Pollock, Antoine Allanore, Amy J. Clarke, Jonathan Cormier, Matthias Militzer, Jian-Feng Nie, Sridhar Seetharaman, Il Sohn
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2020)
Article
Engineering, Mechanical
Alice Cervellon, Luciana Maria Bortoluci Ormastroni, Zeline Hervier, Tresa M. Pollock, Fernando Pedraza, Jonathan Cormier
Summary: The study showed that a recrystallized layer thicker than the size of larger casting pores drastically reduces the fatigue life of the Ni-based single-crystal superalloy CMSX-4 at 1000 degrees C. Additionally, the recrystallized layer and roughness introduced by grit-blasting degrade the environmental resistance of the alloy and its resultant fatigue life. Moreover, the fatigue life of the coated specimens is greatly reduced by damage accumulation in the interdiffusion zone caused by grain boundary cracking, oxidation, and internal nitridation.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Nanoscience & Nanotechnology
Sean P. Murray, Alice Cervellon, Jonathan Cormier, Tresa M. Pollock
Summary: Research shows that fatigue crack initiation is mainly influenced by oxidation-assisted surface cracking in air, while the fatigue performance improves under vacuum due to the presence of internal casting pores. Additionally, recrystallized regions on the fracture surfaces of both alloys in the vacuum test condition have been identified, which was not previously reported for single crystal Ni-base alloys.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Lucille Despres, Sophie Costil, Jonathan Cormier, Patrick Villechaise, Romain Cariou
Summary: Surface laser texturing is used to enhance mechanical anchoring and adhesion between interfaces of thermal barrier coating systems. This study analyzed microstructural evolutions in different Ni-based single crystal superalloys during infrared nanosecond laser ablation, and compared thermal-affected volumes for different alloys. The research found that all studied single crystal superalloys behaved similarly during nanosecond laser ablation, suggesting possible non-uniform ablation kinetics between different phases of Ni-based alloys.
Article
Materials Science, Multidisciplinary
Satoshi Utada, Lucille Despres, Jonathan Cormier
Summary: The study found that the creep strength of nickel-based single crystal superalloys at high temperatures is mainly controlled by the remaining γ' volume fraction, with other factors playing a lesser role. The creep exponent for most alloys studied falls within the range of 6-9, indicating that dislocation glide and climb are the rate limiting deformation mechanisms. Damage mechanisms in extreme conditions include necking and recrystallization.
Article
Materials Science, Multidisciplinary
Wenrui An, Satoshi Utada, Xiaotong Guo, Stoichko Antonov, Weiwei Zheng, Jonathan Cormier, Qiang Feng
Summary: This study investigates the effects of overheating and thermal cycling on the creep properties and microstructural evolution of a directionally solidified superalloy. The results show that thermal cycling significantly reduces the creep life and leads to severe microstructural degradation.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Applied
E. Barraud, T. de Resseguier, J. Baillargeat, S. Hemery, J. Cormier
Summary: In this study, the dynamic behavior of a nickel-based superalloy under shock loading was investigated using laser-launched flyers. It was found that different microstructures and heat treatment conditions significantly influence the dynamic failure mechanisms.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Jean Charles Stinville, Lorena Mataveli Suave, Florent Mauget, Lionel Marcin, Patrick Villechaise, Tresa M. Pollock, Jonathan Cormier
Summary: The low and high temperature transverse creep behavior of a directionally solidified Ni-based superalloy DS200 is investigated in this study. In-situ creep tests with strain measurements are conducted to capture the creep strain evolution in individual crystallographic grains. The microstructure configurations promoting damage nucleation are also identified as a function of the loading condition, with high angle grain boundaries being the preferred sites for crack nucleation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Chemistry, Physical
Wenrui An, Satoshi Utada, Stoichko Antonov, Song Lu, Silang He, Fan Lu, Weiwei Zheng, Longfei Li, Jonathan Cormier, Qiang Feng
Summary: Thermal cycling creep tests were conducted on the directionally solidified superalloy DZ125 to simulate overheating conditions. The microstructural evolution and creep mechanism at different stages were characterized. Results showed three creep stages and the harmful effects of decreased gamma' volume fraction and deteriorated grain boundary. The coupled effect of overheating and thermal cycling damage accelerated creep deformation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
M. Huguet, G. Boissonnet, G. Lotte, J. Cormier, P. Villechaise, G. Bonnet, F. Pedraza
Summary: This paper investigates the initial oxidation stages of additive manufactured Rene 65 Ni-based superalloy between 700 and 900 degrees C in air and argon for 48 h, with different building directions and heat treatments. The only factor that impacts the oxidation behavior is the oxidizing atmosphere. The resulting oxide scales are composed of NiCr2O4 and Cr2O3 at 700 degrees C, while at 800 and 900 degrees C, an external Cr2O3 layer forms on top of an internal layer of alpha-Al2O3 due to lower oxygen partial pressure underneath the chromia layer.
Article
Engineering, Mechanical
Cesar-Moises Sanchez-Camargo, Yves Nadot, Jonathan Cormier, Fabien Lefebvre, Wen Hao Kan, Louis Ngai Sum Chiu, Chen Li, Aijun Huang
Summary: A study was conducted on Laser Powder Bed Fusion Inconel 718 to investigate the influence of defects and microstructure on high-cycle fatigue life. It was found that printing orientation had minimal effect on fatigue life, with most failures attributed to lack of fusion defects. The influence of defects was greater at 20 degrees C compared with 650 degrees C. Hot isostatic pressure treatment improved fatigue resistance. Natural cracks propagated in a similar manner to long cracks.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Yawei Li, Dong Wang, Yufeng He, Luciana Maria Bortoluci Ormastroni, Li Wang, Jonathan Cormier, Jian Zhang
Summary: The VHCF behavior of a Ni-based single crystal superalloy treated by different processes was studied. HRS and LMC samples showed cracks initiating from casting pores surrounded by a rough zone. The rotation of γ' within the rough zone was related to the operation of {1 1 1}(110) and {111}(11 2) slip systems. HRS+HIP specimens exhibited the best VHCF property with failure mainly occurring on the surface, while LMC process increased VHCF durability similar to HIP treatment, especially under low loading conditions.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Multidisciplinary
J. Cormier, P. Gadaud, M. Czaplicki, R. Y. Zhang, H. B. Dong, T. M. Smith, F. Zhang, J. S. Tiley, S. L. Semiatin
Summary: Two in-situ test techniques were used to study the isothermal precipitation kinetics in superalloy 718. The observations suggested sequential periods of rapid volume fraction increase followed by a gradually-decreasing rate of change. Avrami exponents decreased with increasing temperature, and numerical simulations highlighted the competition between nucleation and growth in determining transformation kinetics.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
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)
