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rare Metals 2010年第5期29卷 444-450页

作者： XIE Zhiwei ZHANG Yongzhang YANG Yuanzheng CHEN Xianzhao TAO Pingjun Faculty of Material and Energy Guangdong University of Technology Guangzhou 510006 China

Cu46Zr47-xA17Mx （M = Ce, Pr, Tb, and Gd） bulk metallic glassy （BMG） alloys were prepared by copper-mold vacuum suction casting. The effects of rare-earth elements on the glass-forming ability （GFA）, thermal stability, and mechanical properties of Cu46Zr47-xA17Mx were investigated. The GFA of Cu46Zr47-xA17Mx （M = Ce, Pr） alloys is dependent on the content of Ce and Pr, and the optimal content is 4 at.%. Cu46Zr47-xA17Thx（X = 2, 4, and 5） amorphous alloys with a diameter of 5 mm can be prepared. The GFA of Cu46Zr47-xA17Gdx（x = 2, 4, and 5） increases with increasing Gd. Tx and Tp of all decrease. Tg is dependent on the rare-earth element and its content. ATx for most of these alloys decreases except the Cu46Zra2Al7Gd5 alloy. The activation energies △Eg, △Ex, and △Ep for the Cu46Zr42A17Gd5 BMG alloy with Kissinger equations are 340.7, 211.3, and 211.3 kJ/mol, respectively. These values with Ozawa equations are 334.8, 210.3, and 210.3 kJ/mol, respec- tively. The Cu46Zr45Al7Tb2 alloy presents the highest microhardness, Hv 590, while the Cu46Zr43A17Pr4 alloy presents the least, Hv 479. The compressive strength （at.f.） of the Cu46Zra3A17Gd4 BMG alloy is higher than that of the Cu46Zr43Al7Tb4 BMG alloy.

关键词： amorphous materials metallic glass rare-earth elements suction casting glass-forming ability mechanical property

Synergistic Effect of Core/Shell‑Structured Composite Fibers:Efficient Recovery of rare‑earth elements from Spent NdFeB Permanent Magnets

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Advanced Fiber Materials 2024年第6期6卷 1729-1745页

作者： Youngkyun Jung Yun Lee Su‑Jin Yoon Jae‑Woo Choi Center for Water Cycle Research Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Department of Chemical and Biological Engineering Korea UniversitySeoul 02841Republic of Korea Department of Energy and Environment Technology KIST SchoolKorea University of Science and TechnologySeoul 02792Republic of Korea

NdFeB magnets are third-generation permanent magnets that are employed as indispensable components in various ***,rare-earth elements(REEs)such as Dy and Nd must be efficiently recovered from end-of-life magnets to enable resource circulation and reinforce unstable supply *** that end,this paper reports synergistically performing core/shell-structured composite fibers(CSCFs)containing sodium polyacrylate and nanoporous zeolitic imidazolate framework-8(NPZIF-8)nanocrystals as a readily recoverable adsorbent with an exceptional REE-adsorbing *** CSCF core forms an NPZIF-8 nanocrystal shell on the fiber surface as well as draws REEs using its dense sodium carboxylate groups into the NPZIF-8 nanocrystal lattice with high specific surface *** CSCFs exhibit significantly higher maximum adsorption capacities(468.60 and 435.13 mg·g-1)and kinetic rate constants(2.02 and 1.92 min-1)for the Nd3+and Dy3+REEs than those of previously reported REE ***,the simple application of the CSCFs to an adsorption reactor considerably mitigates the adsorbent-shape-induced pressure drop,thereby directly influencing the energy efficiency of the ***,the high REE-recovery ability,tractability,and recyclability of the CSCFs offers a pragmatic pathway to achieving cost-effective REE ***,this study provides new insights into designing synergistically performing core/shell architectures for feasible REE recovery.

关键词： Core/shell structures Fibrous adsorbents Synergistic adsorption Metal resource recovery Pressure drop rare-earth elements

Geochemical characteristics and their significances of rare-earth elements in deep-water well core at the Lingnan Low Uplift Area of the Qiongdongnan Basin

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Acta Oceanologica Sinica 2014年第12期33卷 81-95页

作者： SUN Zhipeng ZHAI Shikui XIU Chun LIU Xinyu ZONG Tong LUO Wei LIU Xiaofeng CHEN Kui LI Na Zhanjiang Branch of China National Offshore Oil Corporation (CNOOC) Limited Key Laboratory of Submarine Geosciences and Technology of Ministry of Education Ocean University of China

A geochemical analysis of rare-earth elements （REEs） in 97 samples collected from the core of deep-water Well LS-A located at the Lingnan Low Uplift Area of the Qiongdongnan Basin is conducted, with the pur-pose of revealing the changes of sedimentary source and environment in the study region since Oligocene and evaluating the response of geochemical characteristics of REEs to the tectonic evolution. In the core samples, both∑REE and∑LREE （LREE is short for light-group REEs） fluctuate in a relatively wide range, while∑HREE （HREE is short for heavy-group REEs） maintains a relatively stable level. With the stratigraphic chronology becoming newer, both∑REE and∑LREE show a gradually rising trend overall. The∑REE of the core is relatively high from the bottom of Yacheng Formation （at a well depth of 4 207 m） to the top of Ledong Formation, and the REEs show partitioning characteristics of the enrichment of LREE, the stable content of HREE, and the negative anomaly of Eu to varying degrees. Overall the geochemical characteristics of REEs are relatively approximate to those of China＇s neritic sediments and loess, with significant ＂continental ori-entation＂. The∑REE of the core is relatively low in the lower part of Yacheng Formation （at a well depth of 4 207-4 330 m）, as shown by the REEs partitioning characteristics of the depletion of LREE, the relative enrich-ment of HREE, and the positive anomaly of Eu; the geochemical characteristics of REEs are approximate to those of oceanic crust and basalt overall, indicating that the provenance is primarily composed of volcanic eruption matters. As shown by the analyses based on sequence stratigraphy and mineralogy, the provenance in study region in the early Oligocene mainly resulted from the volcanic materials of the peripheral uplift ar-eas; the continental margin materials from the north contributed only insignificantly; the provenance devel-oped to a certain extent in the late Oligocene. Since the Miocene, the provenance ha

关键词： Qiongdongnan Basin deep-water well core rare-earth elements sedimentary source andenvironment response to tectonic movement

Aqueous geochemistry of rare-earth elements in karst lakes, southwestern China

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Acta Geochimica 2006年第S1期 171-171页

作者： Zhongliang WANG, Congqiang LIU, Zhaozhou ZHU State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China

Design of the rare-earth-containing materials based on the micro-alloying phase equilibria, phase diagrams and phase transformations

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Journal of Materials Science & Technology 2023年第20期151卷 119-149页

作者： Kai Xu Chengcheng Zhan Ming Lou Xuelian Xiao Ruonan Zhou Fangming Wang Xiaofei Hu Yuan Yuan Keke Chang Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

rare-earth(RE)elements,known as“industrial vitamins”,have permeated modern lives,especially in high-tech *** the RE elements possess close chemical similarities and have been treated as“one element”in the periodic table,their characteristics differ from each *** RE microalloying effect is the crux to ameliorate the physicomechanical and thermochemical properties of materials,thereby the study of RE-related phase diagrams becomes indispensable to the design and optimization of RE-containing ***,in reality,the knowledge base in this area is considerably scarce compared with that of other commonly-used *** this work,the phase equilibria,phase diagrams,phase transformations,and some recent examples of RE-containing materials design are summarized,with which one can predict the RE solubilities,the RE precipitates,as well as the corresponding service *** attainment of enhanced materials’properties suggests that the thermodynamic rules extracted from the phase diagrams could serve as fundamental criteria for the successful development of novel RE-containing materials.

关键词： rare-earth elements Phase diagrams CALPHAD Phase transformations Materials design

Recent developments and applications on high-performance cast magnesium rare-earth alloys

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Journal of Magnesium and Alloys 2021年第1期9卷 1-20页

作者： Guohua Wu Cunlong Wang Ming Sun Wenjiang Ding National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China

During the past decades,with the increasing demands in lightweight structural materials,Mg alloys with low density and high performance have been extensively investigated and partly applied in some *** when rare earth(RE)elements are added as major alloying elements to Mg alloys,the alloy strength and creep resistance are greatly improved,which have promoted several series of Mg-RE *** paper reviews the progress and developments of high-performance Mg-RE alloys in recent years with emphasis on cast *** main contents include the alloy design,melt purification,grain refinement,castability,novel liquid casting and semisolid forming approaches,and the industrial applications or trials made of Mg-RE *** review will provide insights for future developments of new alloys,techniques and applications of Mg alloys.

关键词： Magnesium alloys rare-earth elements High-performance Developments Applications Cast

Research progress on corrosion behaviors and biocompatibility of rare-earth magnesium alloys in vivo and in vitro

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Journal of rare earths 2023年第12期41卷 1827-1842,I0001页

作者： Yuan Zhang Yun Liu Ruining Zheng Yaqi Zheng Liansheng Chen Key Laboratory of the Ministry of Education for Modern Metallurgy Technology North China University of Science and TechnologyTangshan063210China School of Metallurgy and Energy North China University of Science and TechnologyTangshan063210China

As yet,Mg alloys acting as the medical implants have drawn extensive attention,due to their spontaneous degrada bility,effective load-transmissibility and the excellent biocompatibility,particularly in bone tissue reconstruction and vascular ***,they were inevitably affected by the tension/compression-torsion,dynamic erosion and corrosion fatigue under complex service conditions,which lead to premature failure of ***-alloying addition is an effective way to delay the rapid degradation,especially in rare-earth micro-composite *** can not only reduce intensities of galvanic-corrosion by refining the grain sizes and adjusting the Volta-potentials distribution of the precipitates,but also modify the compositions and biocompatibility of the degradation ***,the higher compress tress on the surface can improve the stability and densification of the film layer,which enhanced the corrosion ***,the latest research progress about in vivo/vitro degradation behavio rs and bioco mpatibility of rare-earth Mg alloys is reviewed;The internal relationships between rare-earth elements,phase features and degradation behaviors of Mg alloys are ***,the effects of rare-earth addition on the film-characteristics are deeply explained,and the induced mechanisms of rare earth elements on the biocompatibility are revealed.

关键词： Mg alloys rare-earth elements Microstructure Degradation behaviors Biocompatibility

Preternatural Hexagonal High-Entropy Alloys: A Review

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Acta Metallurgica Sinica(English Letters) 2020年第8期33卷 1033-1045页

作者： Rui-Xuan Li Jun-Wei Qiao Peter K. Liaw Yong Zhang Beijing Advanced Innovation Center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology Beijing30 Xueyuan RoadBeijing 100083China Research Center for High-Entropy Alloys College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA

Recently,various topics on high-entropy alloys have been reported and great amounts of excellent properties have been investigated,including high strength,great corrosion resistance,great thermal stability,good fatigue and fracture properties,*** all these research activities,high-entropy alloys tend to form face-centered-cubic(FCC)or body-centeredcubic(BCC)solid solutions due to their high-entropy stabilization effect,while the hexagonal structures are rarely *** to now,the reported hexagonal high-entropy alloys are mainly composed of rare-earth elements and transitional *** phase transformation and magnetic properties have also aroused wide *** study summarizes the above results and provides the forecast to the future.

关键词： High-entropy alloys Hexagonal close-packed structure Phase formation rules rare-earth elements Multiple-based-element(MBE)alloys

Perspectives for the recovery of rare earths from end-of-life fluorescent lamps

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Journal of rare earths 2014年第3期32卷 195-200页

作者： K.Binnemans P.T.Jones Department of Chemistry KU Leuven – University of LeuvenCelestijnenlaan 200F- box 2404 B-3001 Heverlee Belgium Department of Metallurgy and Materials Engineering KU Leuven – University of LeuvenKasteelpark Arenberg 44 - box 2450 B-3001 Heverlee Belgium

This vision paper discusses the advantages and disadvantages of the three main options for the recycling of rare-earth ele- ments from end-of-life fluorescent lamps：（1） direct re-use of the lamp phosphor mixture; （2） separation of the lamp phosphor mixture into the different phosphor components; （3） recovery of the rare-earth content. An overview is given of commercial activities in Europe in the domain of recycling of materials from end-of-life fluorescent lamps and the recovery of rare earths from these lamps. The collection of end-of-life fluorescent lamps is currently driven by a legal framework that prohibited the release of mercury to the environment. The contaminations of the lamp phosphor powders by mercury and by small glass particles of crushed fluorescent lamps are limiting factors in the recycling process. Research should be directed to an advanced clean-up of the reclaimed lamp phosphor fraction, and in particular to the removal of mercury and glass fragments. The recovery of rare earths from the lamp phosphors could be facilitated by taking advantage of the differences in resistance of the different lamp phosphors by chemical attack by inorganic ac- ids and bases.

关键词： balance problem fluorescence lamps lamp phosphors lanthanides rare-earth elements recycling urban mining

Characteristics of carbonatites from the northern part of the Korean Peninsula: A perspective from distribution, geology and geochemistry

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Geoscience Frontiers 2021年第1期12卷 173-181页

作者： Jinkon Ju Yunsong Kim Mansik Gang School of Resource and Exploration Engineering Kim Chaek University of TechnologyPyongyangNorth Korea Central Survey Group of Mineral Resources PyongsongNorth Korea

The present study introduces the carbonatite in the northern part of the Korean Peninsula for the first *** exploration and development of the phosphorus-bearing carbonate rocks in the area have accumulated new geological data which gave us an opportunity to study origin of the carbonate *** conducted geological survey,geochemical analyses of trace elements and rare earth elements,and carbon and oxygen isotope analyses for the carbonatites from Ssangryong,Pungnyon,Yongyu and Puhung districts of the northern part of the Korean *** research confirms that the phosphorus-bearing carbonate rocks are carbonatite originating from the *** studied carbonatites are distributed at the junctions of ring and linear structures or around their margins and contain a greater amount of REEs,Y,and Sr than carbonate *** carbonatites in Yongyu and Puhung area show evidence that they were formed from mantle plume generated at the lower mantle and display similar fractionation characteristics to carbonatites in Barrado Itapirapua in Brazil and Kalkfeld and Ondurakorume in *** patterns of the carbonatites are typical of carbonatites and the carbon and oxygen isotope analyses demonstrate that the carbonatites were originated from *** carbonatites from the northern part of the Korean Peninsula have a great potential for sources of REE,Y,PGE(platinum group elements),copper,and gold.

关键词： Carbonatite rare-earth elements Stable isotope composition Phoscorite Platinum group elements Korean Peninsula