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Journal of Materials Science & Technology 2022年第9期104卷 81-87页

作者： Shengfeng Zhou Min Xie Changyi Wu Yanliang Yi Dongchu Chen Lai-Chang Zhang MOE Key Lab of Disaster Forecast and Control in Engineering Jinan UniversityGuangzhou 510632China School of Materials Science and Engineering Tianjin Polytechnic UniversityTianjin 300387China Department of Educational Science Hunan First Normal UniversityChangsha 410205China School of Materials Science and Energy Engineering Foshan UniversityFoshan 528225China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia

To overcome the dimension limits of immiscible alloys produced by traditional techniques and enhance their mechanical properties,bulk Cu-Fe-based immiscible alloy with abundant nanotwins and stacking faults was successfully produced by selective laser melting(SLM).The SLM-produced bulk immiscible alloy displays a heterogeneous microstructure characterized by micro-scaledγ-Fe particles dispersed in fineε-Cu matrix with a high fraction(~92%)of high-angle grain ***,abundant nanotwins and stacking faults are generated in the interior of nano-scaledγ-Fe particles embedded withinε-Cu *** heterogeneous interface of soft domains(ε-Cu)and hard domains(γ-Fe)not only induces the geometrically necessary dislocations(GNDs)but also affects the dislocation propagation during plastic ***,the bimodal heterogeneous interface,and the resistance of nanotwins and stacking faults to the propagation of partial dislocation make the bulk immiscible alloy exhibit an enhanced strength of~590 MPa and a good ductility of~8.9%.

关键词： immiscible alloy Selective laser melting Heterogeneous microstructure Nanotwins Stacking faults

Effect of high magnetic field on solidification microstructure evolution of a Cu-Fe immiscible alloy

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China Foundry 2022年第4期19卷 335-341页

作者： Yu-jie Yan Chen Wei Yi-xuan He Chao Li Ping-xiang Zhang Jin-shan Li Jun Wang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Xi'an Superconducting Magnet Technology Co. Ltd.Xi'an 710018China Northwest Institute for Nonferrous Metal Research Xi'an 710016China

The liquid phase separation behavior and the evolution of the solidification microstructure of a binary Cu_(50)Fe_(50) alloy were investigated under the conditions of without and with a 10 T magnetic field,with different undercooling during the solidification *** show that the combined effect of Stokes motion and Marangoni convection leads to the formation of the core-shell structure under the condition without the magnetic *** addition,specific gravity segregation is reinforced by increasing the undercooling,resulting in Fe-rich phase drifts towards the sample *** the 10 T magnetic field,the Fe-rich phase is elongated in the parallel direction of the magnetic field under the action of demagnetization energy due to the difference of static magnetic energy and surface *** the vertical direction,through the action of Lorentz force,the convection in the melt is inhibited and Fe-rich phase becomes more ***,the diffusion of the two phases and the coagulation of the Fe-rich phases are also restrained under the magnetic field,therefore,the phase volume fraction of the Fe-rich phase decreases at the same undercooling in the 10 T magnetic *** magnetic field inhibits the segregation behavior in the vertical direction of the magnetic field,and at the same time,improves the gravitational segregation to a certain extent,which has a very important impact on microstructure regulation.

关键词： high magnetic field Cu-Fe immiscible alloy undercooling solidification

Observation of Bi Coarsening and Dissolution Behaviors in Melting Al–Bi immiscible alloy

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 800-803页

作者： Wen-Quan Lu Shu-Guang Zhang Jian-Guo Li School of Materials Science and Engineering Shanghai Jiao Tong University School of Environmental Science and Engineering Shanghai Jiao Tong University

Using synchrotron radiography, a melting process of the AI-10 wt% Bi immiscible alloy was fully observed, and Bi solute coarsening and dissolution behaviors as well as their effect on the microstructural evolution were also investi- gated. We found that two different steps including coarsening and dissolution processes can be used to describe the structure evolution in melting AI-10 wt% Bi immiscible alloy. And diffusion coalescence controlled the coalescence of Bi droplets at the early stage of the melting AI-10 wt% Bi immiscible alloy, while the coagulation dttring movement did at later stage. Also, the larger the droplet, the larger the distance of the steady-state concentration distribution around the droplet.

关键词： immiscible alloy Coarsening Dissolution Synchrotron radiography

Comparison of dendrite and dispersive structure in rapidly solidified Cu-Co immiscible alloy with different heat flow modes

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Transactions of Nonferrous Metals Society of China 2017年第1期27卷 227-233页

作者：李圣刘峰杨伟西北工业大学凝固技术国家重点实验室西安710072 南昌航空大学航空制造工程学院南昌330063

Rapid solidification of Cu-Co immiscible alloy was investigated by glass-fluxing, spray casting and melt-spinning techniques. Both the transition from dendrite to dispersive structure and corresponding scale evolution were revealed and further elucidated in terms of the heat flow mode, nucleation and growth processes under different solidification conditions. With the increase of undercooling, columnar dendrite is replaced by dispersive structure due to the immiscible effect. In contrast, equiaxed dendrite forms in spray cast alloy due to multiple nucleation events and becomes thinner for the case of higher cooling rate. Ascribed to the enhanced non-equilibrium effect and insufficient period for collision and coagulation processes between separated droplets, fine globular dispersion appears upon the diameter of spray casting reaching 4 mm. As for the melt-spun ribbon with the highest cooling rate, a single-phase solid solution microstructure with refined grain of cellular morphology can be obtained, which is attributed to the suppression of liquid phase separation by instant solidification.

关键词： rapid solidification immiscible alloy microstructure nucleation growth

Modeling and Simulation of the Microstructure Evolution during a Cooling of immiscible alloys in the Miscibility Gap

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Journal of Materials Science & Technology 2002年第3期18卷 197-205页

作者： JiuzhouZHAO L.Ratke 等 TheInstituteofMetalResearch ChineseAcademyofSciencesShenyang110016China TheInstituteforSpaceSimulation DLRD-511470CologneGermany

The microstructure development during a cooling period of alloys being immiscible in the liquid state such as Al-Pb or AI-Bi has gained renewed scientific and technical interest during the last decades. Experiments have been performed to investigate the phase transformation kinetics in the liquid miscibility gap and numerical models have been developed to simulate and analyze the solidification process. The recently developed computational modeling techniques can, to some extent, be applied to describe the decomposition, the spatial phase separation and the microstructure evolution during a cooling period of an immiscible alloy through the miscibility gap. This article overviews the researches in this field.

关键词： immiscible alloy Solidification Microstructure Modeling

Model for calculation of microstructural development in rapidly directionally solidified immiscible alloys

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Transactions of Nonferrous Metals Society of China 2002年第3期12卷 366-369页

作者：赵九洲 Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

A model has been developed for the calculation of the microstructural evolution in a rapidly directionally solidified immiscible alloy. Numerical solutions have been performed for Al Pb immiscible alloys. The results demonstrate that at a higher solidification velocity a constitutional supercooling region appears in front of the solid/liquid interface and the liquid liquid decomposition takes place in this region. A higher solidification velocity leads to a higher nucleation rate and, therefore, a higher number density of the minority phase droplets. As a result, the average radius of droplets in the melt at the solid/liquid interface decreases with the solidification velocity.

关键词： immiscible alloy directional solidification microstructure theory and modeling

Effect of Brownian Coagulation on the Liquid-liquid Decomposition in Gas-atomized alloy Drops

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Journal of Materials Science & Technology 2006年第3期22卷 321-323页

作者： Jiuzhou ZHAO Lingling GAO Jie HE L.Ratke Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China The Institute for Space Simulation DLR 51140 Cologne Germany

Modeling and simulation have been carried out for Al-Pb alloys to investigate the Brownian coagulation effect on the microstructure development in a gas-atomized drop during the liquid-liquid decomposition. The results indicate that Brownian coagulation has a weak effect on the nucleation and a relatively strong effect on coarsening the minority phase droplets. The influence of Brownian coagulation on the liquid-liquid decomposition decreases with the increase in the diameter （or the decrease in the cooling rate） of the atomized drop.

关键词： immiscible alloy Rapid solidification Atomization Brownian coagulation Modeling

Laser powder b e d fusion of copper matrix iron particle reinforced nanocomposite with high strength and high conductivity

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Journal of Materials Science & Technology 2023年第3期134卷 50-59页

作者： Yingang Liu Jingqi Zhang Qiang Sun Meng Li Ming Yan b Xing Cheng Miaoquan Li Ming-Xing Zhang School of Mechanical and Mining Engineering The University of QueenslandSt.LuciaQLD 4072Australia Department of Materials Science and Engineering and Shenzhen Key Laboratory for Additive Manufacturing of High-performance Materials Southern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China

Liquid-liquid phase separation,and the resulted solute segregation,during conventional solidification have been a long-term challenge to produce copper(Cu)-iron(Fe)immiscible composites with high strength and high *** present work reports an effective solution to this issue through laser powder bed fusion(L-PBF)in-situ alloying of Cu-8 wt.%*** observation showed that the fast cooling within micron-scale melt pools fully eliminated the Fe segregation and therefore the L-PBF fabricated nanocomposite achieved the homogeneous microstructure,which featured equiaxed fine grains around 1μm in *** of the nanocomposite at 600℃for 1 h enabled precipitation of two types of *** is coarser Fe nanoprecipitates with body-centered cubic(BCC)structure and diam-eter of 100-300 nm,mainly distributing along grain *** other is smaller Fe nanoprecipitates with face-centered cubic(FCC)structure and diameter of 10-35 nm,being observed within the grains and having coherent interfaces with the Cu *** a result,the aged Cu-Fe nanocomposite achieved tensile strength of 462.9±6.6 MPa with 30.4%±1.7%elongation to failure and 74.5%IACS(International Annealed Copper Standard)electrical *** formation mechanisms of the nanoprecipitates and the strengthening mechanisms of the nanocomposite are discussed.

关键词： immiscible alloy Copper Laser powder bed fusion Ageing Nanocomposite

Phase evolution of binary immiscible Al-Sn film

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Rare Metals 2022年第12期41卷 4241-4247页

作者： Xiao-Meng Pan Hui-Ping Duan School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Binary immiscible Al-Sn alloy is a very important potential anode material for lithium ion *** phase stability and separation process of Al-Sn film,fabricated by magnetron co-sputtering method,was investigated by X-ray diffractometer(XRD),differential scanning calorimetry(DSC) and in situ transmission electron microscopy(TEM) and explained by Miedema theoretical *** analysis reveals that the asdeposited Al-Sn film will decompose spontaneously into Al-riched areas and Sn-riched areas because of the positive mixing *** crystallization process takes place when the Al content in the Al-riched area or Sn content in the Sn-riched area *** results show that Al-Sn thin film is composed of an amorphous matrix and well-dispersed composite *** particle contains an Al-riched area and a Sn-riched *** Snriched area crystallizes and swallows up the Al-riched area gradually during heating through uphill diffusion of the Sn *** on the theoretical analysis and experimental results,an empirical model to explain the phase evolution process in the Al-Sn film was proposed.

关键词： immiscible alloy Uphill diffusion Phase evolution Miedema theory

Phase decomposition behavior and its impact on mechanical properties in bulk nanostructured Cu-20 at.%Fe supersaturated solid solution

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Journal of Materials Science & Technology 2024年第18期185卷 207-220页

作者： Maowen Liu Ruixiao Zheng Hongxing Li Qiuming Wei Chaoli Ma Nobuhiro Tsuji Tianmushan Laboratory Yuhang DistrictHangzhou 311115China Research Institute for Frontier Science Beihang UniversityBeijing 100191China School of Materials Science and Engineering Beihang UniversityBeijing 100191China Department of Materials Science and Engineering Kyoto UniversityYoshida HonmachiSakyo-kuKyoto 606-8501Japan Department of Mechanical Engineering University of North Carolina at Charlotte9201 University City BoulevardCharlotteNC 28223-0001USA Elements Strategy Initiative for Structural Materials(ESISM) Kyoto UniversityYoshida HonmachiSakyo-kuKyoto 606-8501Japan

Extended solid solution of immiscible systems,achieved by extreme processing approaches,can be trans-formed into nanostructured composites via phase decomposition,which are drawing great research atten-tion for their excellent thermal stability and high *** we fabricated the supersaturated solid solution of Cu-20 at.%Fe,a typical immiscible alloy,in bulk state by high pressure torsion,which pro-vides a great freedom over powders for studying the microstructure evolution and mechanical properties in the process of the phase decomposition in immiscible *** found that in the Cu-Fe solid solu-tion,spinodal decomposition of the Fe phases took place at the initial stage of annealing through volume *** process gives rise to:(1)metastableγ-Fe particles in the Cu grains with coherent Fe/Cu interface,and(2)the more stableα-Fe phase at the grain *** process was accompanied by moving boundary reaction which first proceeded in the pattern of spinodal decomposition and then changed into classical nucleation-growth mode with the depletion of Fe atoms in *** resultant Cu-Fe nanocomposites were jointly strengthened by the ultrafine Cu andα-Fe grains according to the rule of mixture,including grain boundary strengthening and the hardening of nanoscaleγ-Fe precipitates in the Cu *** effects of different strengthening mechanisms were scrutinized and their contributions to mechanical properties were quantitatively *** work sheds light onto the opportunity of designing and fabricating nanostructured composites via phase decomposition in immiscible systems.

关键词： immiscible alloy high pressure torsion annealing phase decomposition mechanical property