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mechanical alloying of Ag-Cu Immiscible Alloy System

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Journal of Shanghai Jiaotong university(Science) 2006年第1期11卷 84-87页

作者：方芳何淼 National Key Lab. of Nano/Micro Fabrication Technology Key Lab.for Thin Film and Microfabrication of Ministry of Education Inst. of Micro and Nano Science and Technology Shanghai Jiaotong Univ.Shanghai 200030 China

mechanical alloying has been performed in Ag-Cu immiscible alloy system with five different compositions. X-ray diffraction analysis was carried out to determine the structural characterization of the milled powders. Lattice constants of the milled powders were determined and the solubility for Ag in Cu was calculated. The results demonstrated that MA indeed produced a face center cubic (f.c.c.). Cu-based Cu-Ag solid solution and the solid solubility has been extended to x(Ag)=30% for Ag in Cu when the grain size of Cu-based Cu-Ag solid solution is about 10 nm after MA. There is a three-phases co-existence during the process of MA in this alloy system which agrees well with other experimental and theoretical results. Based on the experimental results a formation model was proposed in this paper to understand the formation of Ag-Cu solid solution during MA.

关键词： mechanical alloying Ag-Cu immiscible alloy system solid solubility

Evaluation of the microstructure,thermal and mechanical properties of Cu/SiC nanocomposites fabricated by mechanical alloying

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 475-486页

作者： Essam B.Moustafa Mohammed A.Taha mechanical Engineering Departments Faculty of EngineeringKing Abdulaziz UniversityJeddah 21589Saudi Arabia Solid State Physics Department National Research CentreEl Buhouth St.Dokki12622 GizaEgypt

Nano-sized silicon carbide(SiC:0wt%,1wt%,2wt%,4wt%,and 8wt%)reinforced copper(Cu)matrix nanocomposites were manufactured,pressed,and sintered at 775 and 875℃in an argon atmosphere.X-ray diffraction(XRD)and scanning electron microscopy were performed to characterize the microstructural *** density,thermal expansion,mechanical,and electrical properties were *** analyses showed that with increasing SiC content,the microstrain and dislocation density increased,while the crystal size *** coefficient of thermal expansion(CTE)of the nanocomposites was less than that of the Cu *** improvement in the CTE with increasing sintering temperature may be because of densification of the ***,the mechanical properties of these nanocomposites showed noticeable enhancements with the addition of SiC and sintering temperatures,where the microhardness and apparent strengthening efficiency of nanocomposites containing 8wt%SiC and sintered at 875℃were 958.7 MPa and 1.07 vol%^(−1),*** electrical conductivity of the sample slightly decreased with additional SiC and increased with sintering *** prepared Cu/SiC nanocomposites possessed good electrical conductivity,high thermal stability,and excellent mechanical properties.

关键词： copper matrix nanocomposites silicon carbide coefficient of thermal expansion elastic moduli electrical conductivity mechanical alloying

Phase Transformation in Al/Zn Multilayers during mechanical alloying

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Acta Metallurgica Sinica(English Letters) 2023年第10期36卷 1709-1718页

作者： Chen Chen Junjie Yu Jingyu Lu Jian Zhang Xuan Su Chen-Hao Qian Yulin Chen Weixi Ji Manping Liu Department of mechanical Engineering Jiangnan UniversityWuxi214122China Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan UniversityWuxi214122China School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China

In this work,mechanical alloying of the alternating stacked pure Al and Zn thin foils was accomplished via high-pressure torsion(HPT).In the alloyed Al-Zn system,an exotic phase transformation from hexagonal close-packed(HCP)to face-centered cubic(FCC)was *** atomic-scale evolution process and underlying mechanism of phase transformation down to atomic scale are provided by molecular dynamics simulation and high-resolution transmission electron *** HCP→FCC phase transformation was attributed to the sliding of Shockley partial dislocations generated at the Al-Zn grain boundaries,which resulted in an[2110][011]and(0001)/(111)orientation relationship between the two *** work provides a new approach for the in-depth study of the solid phase transformation of Al-Zn alloys and also shed lights on understanding the mechanical properties of the HPT processed Al-Zn alloys.

关键词： High-pressure torsion Phase transformation Al/Zn multilayers mechanical alloying

Fabrication of Bulk (Fe,Cr)_3Al/Al_2O_3 Intermetallic Matrix Nanocomposite Through mechanical alloying and Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 911-919页

作者： Sayyed Erfan Aghili Mohammad Hossein Enayati Fathallah Karimzadeh Department of Materials Engineering Isfahan University of Technology

In the present study, （Fe,Cr）3Al/20 vol% A1203 nanocomposite was prepared through mechanochemical reactions during ball milling and successfully bulked using a combination of cold isostatic press and sintering at 1400℃ for 1 h. Two processing approaches were utilized to produce （Fe,Cr）3A1/A1203 nanocomposite： The first was milling of Fe, Cr, AI and Fe203, while the second one was milling of Fe, Cr, Al and Cr203, both in stoichiometric condition, to synthesize （Fe,Cr）3Al/20 vol% Al2O3. Structural changes of powder particles during mechanical alloying were studied by X-ray diffraction. The microstructure and the morphology of powder particles and bulk samples were also studied by scanning electron microscopy and transmission electron microscopy. Microstructural analysis showed that mechanochemical reactions took place during milling, and nanometric Al2O3 was uniformly distributed in the matrix. The results also showed that the second approach required a considerably higher milling time to produce （Fe,Cr）3Al/Al2O3 nanocomposite, as compared to the first one. For this reason, bulk samples were produced from the synthesized nanocomposite in the first approach. The microstructure of the sintered samples consisted of a network structure of （Fe,Cr）3Al and Al2O3 phases with superior mechanical properties.

关键词： Iron aluminide mechanical alloying Nanocomposite Mechanochemical treatment

Preparation of Fe-As alloys by mechanical alloying and vacuum hot-pressed sintering:microstructure evolution,mechanical properties,and mechanisms

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Rare Metals 2024年第8期43卷 3876-3892页

作者： Fei Chai Fei-Ping Zhao Zhan Hu Shi-Yi Wen Ben-Hammouda Samia Ze-Lin Fu Xin-Ting Lai Yan-Jie Liang Xiao-Bo Min Li-Yuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Institute of Environmental EngineeringCentral South UniversityChangsha 410083HunanChin State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Building Civiland Environmental EngineeringConcordia UniversityMontreal H3G 1M8Canada

Arsenic materials have attracted great attention due to their unique ***,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low temperature and the high melting point of ***,a new Fe-As alloy was obtained by mechanical alloying(MA) followed by vacuum hot-pressed sintering(VHPS).Moreover,a systematic study was carried out on the microstructural evolution,phase composition,leaching toxicity of As,and physical and mechanical properties of Fe-As alloys with varying weight fractions of As(20%,25%,30%,35%,45%,55%,65%,and 75%).The results showed that pre-alloyed metallic powders(PAMPs) have a fine grain size and specific supersaturated solid solution after MA,which could effectively improve the mechanical properties of Fe-As alloys by VHPS.A high density(> 7.350 g·cm^(-3)),low toxicity,and excellent mechanical properties could be obtained for FeAs alloys sintered via VHPS by adding an appropriate amount of As,which is more valuable than commercial Fe-As *** Fe-25% As alloy with low toxicity and a relatively high density(7.635 g·cm^(-3)) provides an ultra-high compressive strength(1989.19 MPa),while the Fe-65% As alloy owns the maximum Vickers hardness(HVo.5 899.41).After leaching by the toxicity characteristic leaching procedure(TCLP),these alloys could still maintain good mechanical performance,and the strengthening mechanisms of Fe-As alloys before and after leaching were *** in the grain size,micro structure,and phase distribution induced significant differences in the compressive strength and hardness.

关键词： mechanical alloying Vacuum hot-pressed sintering High-pressure Arsenic-iron alloys mechanical properties

Microstructure and mechanical properties of Ti-Cu amorphous coating synthesized on pure Cu substrate by mechanical alloying method

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Rare Metals 2020年第10期39卷 1222-1228页

作者： Cheng Chen Xiao-mei Feng Yi-fu Shen School of mechanical and Power Engineering Nanjing Tech UniversityNanjing 211800China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

mechanical alloying method was applied to fabricate coating with amorphous structure on pure Cu *** microstructure,the phase composition and the mechanical properties including microhardness and wear resistance of the coating were,respectively,characterized and *** results show that the coating is rough but *** has favorable adhesion to the *** coating is made up of an inner composite layer and an outer amorphous *** microhardness and the wear resistance of the pure Cu substrate are improved because of the bilayer *** formation mechanism of the coating was *** as-synthesized coating is considered to be effective to strengthen the surface of pure Cu substrate.

关键词： Coating Amorphous mechanical alloying Surface reinforcement

Influence of B source materials on the synthesis of TiB_2-Al_2O_3 nanocomposite powders by mechanical alloying

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1214-1220页

作者： Majid Abdellahi Javad Heidari Rahman Sabouhi Materials Engineering Department Islamic Azad University

An Al2O3-TiB2 nanocomposite was successfully synthesized by ball milling of Al, TiO2 and two B source materials of B2O3 （system （1）） and H3BO3 （system （2））. Phase identification of the milled samples was examined by Xray diffraction. The morphology and microstructure of the milled powders were monitored by scanning electron microscopy and transmission electron microscopy. It was found that the formation of this composite was completed after 15 and 30 h of milling time in systems （1） and （2）, respectively. More milling energy was required for the formation of this composite in system （2） due to the lubricant properties of HaBO3 and also its decomposition to HBO2 and B2O3 during milling. On the basis of X-ray diffraction patterns and thermodynamic calculations, this composite was formed by highly exothermic mechanically induced self-sustaining reactions （MSR） in both systems. The MSR mode took place around 9 h and 25 h of milling in systems （1） and （2）, respectively. At the end of milling （15 h for system （1） and 30 h for system （2）） the grain size of about 35-50 nm was obtained in both systems.

关键词： nanocomposites powders alumina titanium diboride mechanical alloying

Structure and magnetic properties of Fe-based powders prepared by mechanical alloying

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Acta Metallurgica Sinica(English Letters) 2010年第5期23卷 351-356页

作者： Tingdong ZHOU Zhengyun WANG Jiangkang TANG Haipeng LU Key Laboratory of Special Material and Preparing Technology Xihua University Chengdu 610039 China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Scienceand Technology of China Chengdu 610054 China

FeSiAlCr alloy powders were prepared by mechanical alloying, the milling time were 20 h, 40 h, 60 h and 80 h, respectively. Powders morphology was studied by SEM. Microstructure of powders milled for various times were analyzed by XRD. The complex permittivity and complex permeability of four powders were tested in the frequency range from 0.5 to 18 GHz, and their microwave absorption properties were analyzed. It was found that the particle size of powders milled for 80 h was less than 2 μm. Silicon and aluminum atoms were dissolved into the crystal lattice of iron, and chromium atoms can form alloy with iron atoms. The minimum peak value of reflectivity can reach to -11.3 dB at the frequency of 4.3 GHz for 80 h milling powders, and the other one was ？6 dB at 16.5 GHz.

关键词： FeSiAlCr alloy Solid solution Electromagnetic parameter Reflectivity mechanical alloying

Thermodynamic Aspects of Nanostructured CoAl Intermetallic Compound during mechanical alloying

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Journal of Materials Science & Technology 2011年第7期27卷 601-606页

作者： S.N. Hosseini T. Mousavi F. Karimzadeh M.H. Enayati Department of Materials Engineering Nanotechnology and Advanced Materials Institute Isfahan University of Technology84156-83111 Iran

The nanostructured CoAl intermetallic compound was produced by mechanical alloying （MA） of the Co50Al50 elemental powder mixture in a planetary high energy ball mill. The ordered B2-CoAl structure with the grain size of about 6 nm was formed via a gradual reaction after 10 h of MA. A thermodynamic analysis of the process was also done. The results showed that the intermetallic compound of CoAl had the minimum Gibbs free energy compared to solid solution and amorphous states indicating the initial MA product was the most stable phase in the Co-Al system which was changed to a partially disordered structure with a steady long-range order of 0.82 at further milling. This amount of disordering caused the enthalpy of final product to show an increase of about 5.1 kJ·mol-1. Calculation of enthalpy related to the triple defect formation revealed that the enthalpy required for Al anti-sites formation was about 3 times greater than that for Co anti-sites formation.

关键词： Intermetallics CoAl Nanostructured materials mechanical alloying Thermodynamics