Status of Research on Application of High Purity Rare Earth Oxides in Solid Oxide Fuel Cells

The solid oxide fuel cell (SOFC) is a high-efficient and environmentally friendly power generation system.The rare earth oxide materials are used extensively in the manufacturing of SOFC components.In particular, the CeO2doped with Gd2O3 or Sm2O3, lanthanide perovskite oxides are indispensable and key materials for developing the intermediate temperature SOFC.The research and development status of application of high purity rare earth oxides in SOFC was overviewed.The rare earth oxide-based and -doped materials were discussed for the SOFC components.Concerning the rare earth oxides applicable to SOFC, several topics were also pointed out for further researching and developing.     

Cathode Materials for Solid Oxide Fuel Cells(SOFC)

A detailed overview has been given concerning the use of rare earth materials in cathode fabrica-tion of solid oxide fuel cells(SOFC).It is focused on the various synthesis methods of the perovskite-typemixed rare earth oxides and the physical and chemical properties of the materials for cathode application ofSOFC.Also discussed is the doping mechanism of the related materials.Documented investigations showthat lanthanide of transition metals,especially manganese,chromium doped with strontium are most advan-tageous for the application.The crystallography,defect structure,conductivity and thermal matching withthe electrolyte and high temperature stability of cathode in oxidative gases are particularly emphasized.     

Research and Development of Rare Earth Advanced Materials in China

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Effects of Rare Earths on Properties and Microstructure of Automotive Friction Materials

Rare earth compounds as modifiers used widely in modern friction materials can enhance the interracial binding of constituents of materials and improve the comprehensive properties of materials evidently. However, there are still few reports on application of rare earth in automotive friction materials. In order to study the effect mechanism of rare earths in friction materials, a rare earth compound was selected as additive and the effects of materials doped with or without rare earth on friction and wear properties of materials were studied. The microstructure and worn surface morphology were observed by scanning electron microscopy and the macro performance was discussed. Worn surface element constitution of materials was analyzed by energy dispersive spectroscopy. Effect mechanism of rare earths on friction and wear behaviors of friction materials were discussed. The results show that doping rare earths in friction materials can stabilize friction Coefficient, lower the wear rate of materials and increase the impact strength of materials. The flexibility and fracture resistance of materials is greatly improved. Worn surface of materials doped with rare earth is compact and the surface adhesion is greatly enhanced.     

论稀土材料的现状与发展

对我国稀土材料产品进行了概述，并与世界水平进行对比叙述了稀土永磁材料、稀土汽车尾气净化催化剂、稀土荧光粉、稀土钨电极的现状及国内外发展状况，存在问题，对发展稀土新材料提出了见解。     

Composition, Processing Technology and Property of Ceramic Die Materials Containing Rare Earth Additives

Development and application of new ceramic die materials is one of the important topics in the field of die research. The composition, processing technology, mechanical property and engineering performance of the ceramic materials such as cermet, ZTA, TZP, TZP/Al2O3, TZP/TiC/Al2O3, PSZ and Sialon, etc., with rare earth yttrium, lanthanum and cerium, and so on working as additives, were investigated and analyzed in the present study. Problems existed in the research and application of rare earth ceramic die materials were discussed. Rare earth additives can effectively improve the mechanical property and engineering performance of ceramic die materials. Thus, it will have further perspectives of wider application. More attention should be paid in the future to the toughening and strengthening of the ceramic die materials, the adding forms and kinds of rare earth elements and acting mechanisms of rare earth additives in ceramic die materials.     

稀土固体废物的成因、成分分析及综合利用

根据稀土工业产业链实际情况,就产生批量固体废弃物的工艺过程及稀土材料进行了讨论,对稀土湿法冶金渣、电解渣、铁基稀土永磁材料、钴基稀土永磁材料、稀土贮氢材料、稀土抛光粉、稀土催化剂等固体废物的成因、生成量、成分分析及综合利用进行了综述,并对稀土固体废物的处理及管理提出了建议。     

Formation cause,composition analysis and comprehensive utilization of rare earth solid wastes

Based on practical situation of rare earth industrial chain,production process and rare earth materials that could produce solid wastes on batch were discussed.Formation cause,formation volume,composition analysis and comprehensive utilization of the solid wastes of rare earth hydrometallurgy slag,electrolysis slag,Fe-based rare earth permanent magnetic materials,Co-based rare earth permanent magnetic materials,rare earth hydrogen storage materials,rare earth polishing powders and rare earth catalysts were ...     

稀土发光材料研发及应用进展

从汤森路透、Proquesft Dialog数据库中检索有关稀土发光材料的专利数据,并利用TDA、TI、INNOGRAPHY软件进行分析,探讨稀土发光材料的研发现状及其近年来的研发动向,分析主要国家的技术研发方向和市场布局,比较核心研发企业的专利技术布局、技术方向、竞争结构、技术强度和市场强度,从微观层面研判及预测稀土发光材料的未来技术走向。分析结果表明：中国在稀土发光材料领域申请专利数量位居全球第一;美国和日本在专利质量方面占优;全球稀土发光材料研发方向方面,中国研发方向单一,美国、日本和韩国在诸多研发方向上有较强交叉,表现在红光荧光体组合物、闪烁体组合物、β-Sialon稀土发光材料、纳米稀土发光材料和多晶稀土发光材料等方向。中国企业应该利用节能照明工程方面的政策优势,注重该领域高技术水平发展;同时应充分发挥稀土矿的优势,在涉及钇的发光材料等方向加强研发。     

稀土分析检测方法标准述评

从稀土矿、稀土精矿、稀土金属及其氧化物、稀土深加工产品等方面概述我国稀土分析国家标准体系.其中稀土配分、三氧化二铝、稀土总量、水分、灼减量等参数的检测,是稀土交易和萃取分离工艺过程中重要的技术指标;而钕铁硼、灯用稀土三基色荧光粉、稀土硅铁合金等分析标准,对于稀土磁性材料、稀土发光材料、稀土合金等稀土深加工产品的生产都有重要的指导意义;稀土产品及分析方法的建立,完善了稀土国家标准体系,满足了稀土生产和贸易的需要,促进了稀土行业持续健康发展.      

非水溶剂电还原制取重稀土金属及合金的研究现状及发展

随着重稀土元素对铝、镁、铜、镍及钢铁等金属材料的功能化作用被广泛关注,使得作为战略性资源的重稀土元素在金属合金材料的应用领域拓展空间巨大.在此背景下,作为改性元素的重稀土金属及合金的市场需求必然猛增.由于重稀土单质自身的高熔点,混熔法、真空热还原法一直是生产制备重稀土金属及合金的主要方法,寻求一条低成本、高效、绿色的制备方法则至关重要.由于熔盐电化学还原法在生产低熔点轻稀土及合金工艺方面具有经济、高效等优势,近年来,通过熔盐电解方式直接制取低熔点的重稀土合金成为国内外学者研究的热点,从目前取得进展来看,具有广阔的发展前景.针对国内外重稀土金属及合金的熔盐电解法制取的研究现状进行了评述,从体系物理化学性质、电极过程机理、模拟计算等几个方面做了简要的总结和分析,以期对重稀土合金材料的制备研究提供有益的帮助.      

Formation of intermetallic compound at interface between rare earth elements and ferritic-martensitic steel by fuel cladding chemical interaction

The intermetallic compounds formation at interface between rare earth elements and clad material were investigated to demonstrate the effects of rare earth elements on fuel-cladding chemical interaction(FCCI)behavior.Mischmetal(70Ce-30La)and Nd were prepared as rare earth elements.Diffusion couple testing was performed on the rare earth elements and cladding(9Cr2W steel)near the operation temperature of(sodium-cooled fast reactor)SFR fuel.The performance of a diffusion barrier consisting of Zr and V metallic foil against the rare earth elements was also evaluated.Our results showed that Ce and Nd in the rare earth elements and Fe in the clad material interdiffused and reacted to form intermetallic species according to the parabolic rate law,describing the migration of the rare earth element.The diffusion of Fe limited the reaction progress such that the entire process was governed by the cubic rate law.Rare earth materials could be used as a surrogate for high burnup metallic fuels,and the performance of the barrier material was demonstrated to be effective.     

稀土润滑材料的摩擦学研究

随着稀土材料科学和摩擦学研究的发展 ,近来许多材料工作者注意到了稀土润滑材料的摩擦学性能 ,并开展了一些积极的研究工作。主要讨论了稀土合金、稀土无机化合物、以及稀土配合物的摩擦学研究和作用机制 ,并对稀土润滑材料今后的发展提出了一些建议     

Far Infrared Radiation Property of Rare Earth Mineral Composite Materials

Rare earth mineral composite materials were prepared using rare earths and natural far-infrared mineral materials. The influences of rare earth additive content and heat treatment temperature on the far infrared radiance were studied. The results show that the far infrared radiance of rare earth mineral composite materials is 0.93 when the rare earth additive content is 6% and heat treatment temperature is 750 ℃.     

Effect of rare earth oxides on the properties of bio-soluble alkaline earth silicate fibers

Using natural mineral wollastonite, talc and quartz sands as raw materials, rare earth oxides(La_2O_3, Nd_2O_3 and Y_2O_3) as additives, the bio-soluble alkaline earth silicate fibers were prepared by melting and blowing process. The viscosity of the molten materials, bio-solubility and crystallization behavior of the fiber were investigated. The results indicated that the fiber drawing temperature range could be broadened since the slope of the temperature-viscosity curve decreased with adding rare earth oxide. The addition of rare earth oxide was beneficial to the increase of crystallization temperature by strengthening the network structure of the fiber. The existence of rare earth oxide in the fibers would reduce the solubility of the fibers, which still belonged to bio-soluble fibers.     

稀土粉体性能的评价体系(Ⅱ):颗粒特性的评价

稀土粉体(氢氧化稀土、稀土碳酸盐、稀土草酸盐、稀土氧化物和氟化物等)的颗粒性能方面的指标对稀土新材料的开发具有重要意义.晶粒特性、表面特性、颗粒特性、颗粒群特性和应用特性等五方面构成了稀土粉体性能的评价体系.本文对颗粒特性的评价进行了讨论,颗粒大小分布、颗粒形状、颗粒团聚参数、团聚强度、团聚体结构、孔隙率是描述颗粒特性的六个指标.     

稀土粉体性能的评价体系(Ⅰ)： 晶粒与表面特性的评价

稀土粉体(氢氧化稀土、稀土碳酸盐、稀土草酸盐、稀土氧化物和氟化物等)的颗粒性能方面的指标对稀土新材料的开发具有重要意义。晶粒特性、表面特性、颗粒特性、颗粒群特性和应用特性等五方面构成了稀土粉体性能的评价体系。本文对晶粒特性和表面的评价进行了讨论。晶粒大小和晶体结构是描述晶粒特性的两个指标,比表面积、表面电位、比表面能和表面亲和性是描述表面特性的四个指标。     

国际稀土研究的科学知识图谱分析

以1985-2015年Web of Science（WoS）数据库中已发表的学术论文为基础,利用科学知识图谱分析软件VOSviewer和Sci2工具包对国际稀土研究领域进行可视化分析.首先,通过文献共被引分析稀土研究的知识基础;其次,通过关键词共现分析探测稀土研究前沿;最后,通过突现检测分析稀土研究趋势,并结合我国稀土研究的特点和现状,对我国稀土研究进行综述.结果表明,中国的发文量在国家/地区中居于首位,中国科学院在相关机构中发文量最多;稀土研究知识基础的重要文献形成3个聚类;稀土研究的前沿主题主要为稀土发光材料、稀土永磁材料、稀土储氢材料、稀土化合物和化学合成法5个聚类;稀土研究趋势主要的突现关键词包括稀土化合物、荧光粉等方面.      

Recent advances in nonlinear optical rare earth structures

Nonlinear optical (NLO) crystals can be employed to expand the laser frequency and thus are of technical importance in advanced laser science. Noncentrosymmetric rare earth compounds keep attracting broad interest as a significant branch of NLO materials because the highly distorted structural motifs centered by rare earth ions could remarkably benefit the second harmonic generation. In this review, we proceed from structure–properties relationship and reveal the role of rare earth element in the optical properties of NLO materials. We believe that this work can deepen the understanding of rare earth-based NLO materials and provide some enlightenment for exploring novel practical NLO crystals.     

稀土金属冶炼用新型钨钼材料的研制

本文从稀土金属冶炼用新型钨钼材料的研制着手,研究了添加几种微量稀土氧化物对钨钼材料高温、无保护性气氛下的抗氧化性。研究发现,微量稀土氧化物的添加,减慢了钨钼材料的氧化速度,较大地提高了钨钼材料的抗氧化能力。由于钨钼材料性能的改善,可使稀土冶金、玻璃、纤维等行业用的钨钼材料寿命延长、成本降低。研究表明,使用添加氧化铈、氧化钇、氧化镧的新型钨钼材料,可减少被提炼金属中的钨钼含量,使质量提高,品种上档次,满足日益发展的国内外稀土市场的要求。