Article
Materials Science, Multidisciplinary
Hengcheng Liao, Yuna Wu, Hao Chen, Longjie Qian
Summary: Complete divorced eutectic solidification can be achieved in hypereutectic Al-Si alloys through specific solidification conditions, resulting in significant refinement and nodularization of the Si phase. Two prerequisites for divorced eutectic solidification in hypereutectic Al-Si alloys are observed: abundant crystals of the Si phase present in liquid before the eutectic reaction, and a sufficiently slow cooling rate of the melt as it enters the temperature range of the eutectic reaction.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Reza Haghayeghi, Giulio Timelli
Summary: The experimental results indicate that stacking fault and kinks, in addition to twinning, contribute to primary Si refinement in A390 hypereutectic Al alloy. The type of alloying element determines the major contributing mechanism in primary Si evolution. Furthermore, the kink formation and its effect on primary Si refinement has yet been reported elsewhere.
Article
Chemistry, Physical
Wanwu Ding, Lumin Gou, Liwen Hu, Haixia Zhang, Wenjun Zhao, Jinyuan Ma, Jisen Qiao, Xiaochun Li
Summary: This paper investigates the effects of a novel Al-3Ti-4.35La master alloy on the morphology of eutectic Si and mechanical properties of hypoeutectic Al-7Si alloy, and reveals its modification mechanism. The results show that the addition of Al-3Ti-4.35La master alloy can transform the eutectic Si phase into a fine fiber and partial granular structure, significantly enhancing the ultimate tensile strength and elongation of the alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Xiangzhen Zhu, Shihao Wang, Xixi Dong, Xiangfa Liu, Shouxun Ji
Summary: In this study, the morphologies of AlP crystals were comprehensively studied, revealing two categories of AlP crystals and their morphological templated nucleation of primary Si phase. This process increased the percentage of primary Si twin crystals in the alloy and eliminated dendritic growth and hopper structures inside primary Si, maintaining faceted solid crystals through layer-by-layer growth mechanism. The insight into morphologically templated nucleation provides a new perspective on the mechanism of heterogeneous nucleation of primary Si phase on AlP nuclei.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
T. T. Saravanan, M. Kamaraj, S. C. Sharma, S. Anoop, Sushant K. Manwatkar, K. Ravikanth, A. Venugopal, S. Kumaran
Summary: The spark plasma sintered hypereutectic Al-Si alloy exhibited superior mechanical properties and corrosion resistance compared to conventional cast microstructure, showing higher failure strain and enhanced corrosion resistance in a 3.5 wt% NaCl corrosive medium due to the absence of coarse primary Si and acicular eutectic Si in the SPSed microstructure.
Article
Microscopy
Mengyu Li, Tong Gao, Chunxiao Li, Yue Sun, Yuying Wu, Xiangfa Liu
Summary: An Al-15 Al2O3 alloy was added to the Al-12Si melt to study the effect of Al2O3 nanoparticles on eutectic Si crystals. It was observed that Al2O3 clusters were either partly engulfed by eutectic Si or distributed around them. This resulted in a transformation of flake-like eutectic Si to granular or worm-like structures, influenced by Al2O3 nanoparticles on the growth behavior of eutectic Si crystals. The orientation relationship between Si and Al2O3 was identified, and the possible mechanisms for modification were discussed.
Article
Chemistry, Physical
Qirong Wei, Hongxuan Wang, Jiabin Li, Xiang Quan, Weipo Li, Bin Wang
Summary: This study systematically investigated the microstructure, heat resistance, and creep resistance of Al-11Ce-xSi (x = 0, 0.9, 1.7 wt%) alloys. The addition of Si resulted in the formation of a tetragonal AlCeSi intermetallic compound. The Al11Ce3/α-Al eutectics transformed into rod-like structure and were gradually replaced by broad flaky AlCeSi/α-Al eutectics as the Si content increased. The Al-11Ce alloy containing 0.9 wt% Si exhibited the optimal tensile properties and excellent coarsening resistance.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
William P. Bates, Vivek Patel, Harikrishna Rana, Joel Andersson, Jeroen De Backer, Mattias Igestrand, Livan Fratini
Summary: The present study aims to enhance the mechanical properties of hypereutectic aluminium-silicon castings by modifying the microstructure and reducing defects through friction stir processing (FSP). By altering the tool revolution and the number of FSP passes, the study identified the specimen with the highest number of passes to have the most uniform properties, resulting from reduced casting porosities and refined silicon particle distribution in the friction stir processed zone.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Thermodynamics
Bo Dang, Zengyun Jian, Junfeng Xu
Summary: The effect of ultrasonic melt treatment (UST) on the thermal kinetics of hypereutectic Al-25%Si alloy during eutectic solidification was studied. UST treatment can decrease the activation energy and nucleation energy, leading to the refinement of the eutectic structure.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Nanoscience & Nanotechnology
Lin Zhu, Feng Qiu, Qian Zou, Xue Han, Shi-Li Shu, Hong-Yu Yang, Qi-Chuan Jiang
Summary: A new design method for manipulating the microstructure of Al-Si-Mg alloy using in situ nanosized crystals has been proposed. By analyzing the crystallographic matching relationship and misfit between different phases, the alloy achieved finer grains, refined eutectic Si and Mg2Si, leading to improved mechanical properties.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Masoumeh Faraji
Summary: It was found that Perepezko's nucleation model is not suitable for analyzing data in inoculated hypereutectic Al-Si alloys, while the free growth model by Greer provides a closer approximation for predicting the size of primary silicon in Al-18.6Si (wt pct) alloy inoculated with Al-Fe-P.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Chao Ding, Huali Hao, Zhouguang Lu, Changyang Yu, Xinzhi Wu, Peng Yu, Shulong Ye
Summary: A heat treatment is conducted on Al-20Si powder before hot extrusion to eliminate eutectic Si, which greatly improves the formability and thermal properties of the material. The extruded samples made from the treated powder exhibit excellent mechanical and thermal properties, including high relative densities, high ultimate tensile strength, large elongations, high thermal conductivities, and low coefficients of thermal expansions.
MATERIALS CHARACTERIZATION
(2023)
Article
Metallurgy & Metallurgical Engineering
Junliang Guo, Feng Mao, Guoshang Zhang, Po Zhang, Chong Chen, Changji Wang, Liqiang Xiao, Hong Xu
Summary: The effects of Eu addition on the silicon phase and mechanical properties of hypereutectic Al-16Si alloys were investigated. The addition of Eu resulted in the refinement of the silicon phase and the formation of spheroidal primary silicon and fibrous eutectic silicon. Moreover, it significantly improved the ultimate tensile strength and elongation of the alloy. The refinement of the primary silicon was attributed to constitutional undercooling of the Eu element, while the spheroidization was caused by impurity induced twinning mechanism and poisoning of the twin plane re-entrant due to the adsorption of Eu.
INTERNATIONAL JOURNAL OF METALCASTING
(2023)
Article
Materials Science, Multidisciplinary
Chuanyong Li, Xingguo Zhang, Zhengwei Guo, Lu Li, Quan Shan, Zulai Li
Summary: This article investigates the effect of cooling rate on the distribution of primary phase Si and TiB2 particles in hypereutectic Al-Si alloy. Using a wedge-shaped mold, the effect of cooling rate on the multi-phase structure of TiB2 particles in Al-20Si is studied. The sizes, shapes, and distribution of primary phase Si and TiB2 particles inside primary Si are observed through SEM. The effect of TiB2 particles on cracks in primary phase Si is studied using nanoindentation technology, and the interface relationship between primary Si and TiB2 is studied using TEM. Finally, based on the experimental results, the trapping mechanism of primary Si for TiB2 particles is discussed. The results indicate that the faster the cooling rate, the finer and more uniform the size distribution of the primary Si phase in the structure. TiB2 mostly exists as individual particles and is engulfed by the primary Si phase due to faster solid-liquid interface pushing rate during solidification.
Article
Materials Science, Multidisciplinary
Guodong Ma, Lu Li, Shuaiying Xi, Ying Xiao, Yongkun Li, Zhentao Yuan, Yuanhuai He, Rongfeng Zhou, Yehua Jiang
Summary: The study demonstrated that the addition of TiB2 particles significantly enhanced the strength and ductility of hypereutectic aluminum alloys, by increasing the densities of low-angle and high-angle grain boundaries. Investigations into the TiB2p/Si and TiB2p/Al interfaces were conducted using TEM, HRTEM, and atomic structure model simulations.
MATERIALS CHARACTERIZATION
(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)