| Science and Technology High-Tc Superconductors Sr2CeO4 Blue Phosphor New Materials YSZ Ceramic Coating Reviews Conferences |
|Science and
Technology| |Reviews| |Industry| |RIC| |Conferences| |Calendar| |Supporters| Vol. XXXIV, No. 3 High-Tc Superconductors Studies of High Temperature Superconductors (Advances in Research and Applications) is a series of monographs dealing with the current state of research and commercialization of high temperature superconductors. Hg-Based High Tc Superconductors Part II Volume 24 of the series deals primarily with mercury-based superconductors so only one chapter (Chapter 6 of eight) contains information on rare earth superconductors: High pressure synthesis and properties of HgBa2Can-1CunO2n+2+d , Y2Ba4Cu6+nO14+n, Sr1-xCaxCuO2 and Sr0.73CuO2 Crystals. Crystal growth of Y-124 and Y-247 compounds and the superconducting parameters and flux pinning of Y-124 is covered. Chemistry and Related Aspects of High Tc Superconductors Volume 25 contains two chapters that provide information on the rare earth oxide superconductors: "Classification of Superconducting Oxides as Interstitial Alloys" that may contain more information on superconductor properties than any previous 61 pages of scientific literature in history (256 references). This chapter is highly recommended for students needing a solid background in the field, or for the long-time researcher to remind them how much work has been done the past two decades. "Studies on Preparation and Substitution of YBa2Cu4O8" covers the phases of the homologous series Y2Ba4Cu6+nO14+n, crystal structure, physical properties, and synthesis and substitution in this compound. Quaternary Borocarbides, Superconductors and Hg-Based High Tc Superconductors Volume 26 contains five chapters, the first providing general information on the discovery of Y-Ni-B-C and R-Ni-B-C compounds. The remaining sections pertaining to rare earths include reports on: the interrelation between magnetism and superconductivity in RNi2B2C, material parameters in quaternary borocarbides, including transitions metal doped borocarbides and the effect of thermal treatment; superconducting thin films; and a review of x-ray and neutron powder diffraction analysis of YNi2B2C. The hard cover books are available from Nova Science Publishers, Inc., 6080 Jericho Turnpike – Suite 207, Commack, New York 11725 USA; Tel: 516 499 3103; Fax: 516 499 3146. Volume 24 (244 pages) was published in 1997 and costs US$93.00, Volumes 25 (331 pages) and 26 (202 pages) were both published in 1998 are cost US$93.00 and US$97.00, respectively. A blue emission powder with the composition Sr2CeO4 was prepared by the chemical coprecipitation technique by a team from the Phosphor Technology Center of Excellence, Georgia Institute of Technology, Atlanta, Georgia 30332 USA {Appl. Phys. Lett., 74, [12] (1999)}. The process is claimed to be readily adapted to large-scale commercial production in order to satisfy the phosphor requirements for field emission displays (FEDs). Someday, FEDs may replace cathode ray tubes (CRTs) because they can provide comparable or superior performance than CRTs, but operate at lower excitation voltages (£ 5 kV) and higher current densities (10 – 100 A/cm2). This requires the phosphors to have a high efficiency at low voltages, high resistance to current saturation, long service life, and equal or better chromaticity than phosphors used in CRTs. Current FED phosphors are Ce-doped SrGa2S4 (blue) and Eu-doped SrGa2S4 (green), however, these sulfides have a tendency to decompose during operation and emit sulfide gas, which decreases the luminous efficiency of the phosphors while deteriorating the cathode. Attempts to solve this decomposition by coating the phosphor resulted in decreased luminous efficiency. The solution to these problems seems to have been solved when Sr2CeO4 was prepared last year via a combinatorial materials synthesis technique {Science, 279, 837-9 (1998)}. The oxide phosphor was found to have an orthorhombic crystal structure with one-dimensional chains of edge-sharing CeO6 octahedra, and that the luminescence originates from a ligand-to-metal Ce4+ charge transfer. Although the combinatorial synthesis method provides good results, the product is an oxide thin film, not attractive for large-scale production like chemical production methods. The Sr2CeO4 powder was prepared by dissolving Sr(NO3)2, Ce(NO3)3 × H2O and (NH4)2C2O4 × H2O in water, filtering, precipitating, and separating the products. After drying, Sr2CeO4 was fired at various temperatures but the powder that was subjected to 1200° C for 2 hours had the higher luminous efficiency at both 4 kV and 10 kV. Tests showed that the powder exhibited an emission peak at ~470 nm, and chromaticity coordinates were x = 0.19 and y = 0.26. The authors are confident that this phosphor has potential for field emission displays. Consortium on Advanced Magnets The annual meeting of "Consortium on Advanced Magnets" will be held October 15, 1999 at Wright-Patterson Air Force Base, Dayton, Ohio, USA. The consortium will deal with the current and future trends in permanent magnets and their applications. For more information, contact Helen Long, University of Delaware, Department of Physics & Astronomy, 223 Sharp Lab., Newark, DE 19716 USA; Tel: 302 831 2661; Fax: 302 831 1637; hlong@udel.edu.The NATO ASI conference "Magnetic Storage Systems Beyond 2000" will be held on the Greek Island of Rhodes, June 25 – July 7, 2000. For more information, contact Dr. G.C. Hadjipanayis, University of Delaware, Department of Physics & Astronomy, Newark, DE 19716 USA; Tel: 302 831 2736; Fax: 302 831 1637; hadji@udel.edu. "Rare-Earth-Doped Materials and Devices IV" is conference oe07 of SPIE’s International Symposium on Optoelectronics 2000, Integrated Optoelectronic Devices, and will be held January 22 – 28, 2000. The conference will bring together researchers and engineers from academia and industry to discuss the recent developments in the rapidly growing field of rare earth-doped semiconductors, polymers, laser sources and fiber amplifiers. The conference is open to all aspects of rare earth-doped materials and devices for optical and optoelectronic applications and will include the topics of rare earth-doped materials: glasses, crystals, polymers, semiconductors, hybrid materials, fibers, fiber lasers and amplifiers, planar waveguides, waveguide lasers and amplifiers, light-emitting devices, integrated lasers and amplifiers, miniature solid state lasers, modeling, and new design and fabrication techniques. If interested, contact SPIE, The International Society for Optical Engineering, Tel: 360 676 3290; Fax: 360 647 1445; spie@spie.org. September '99RIC Physics of Strongly Correlated
Electron Systems EUROMAT99 Magnetic and
Superconducting Materials (MSM-99) October '99 November '99 January '00 March '00 May '00 June '00 September '00 September '01 The 25th Volume of the Handbook on the Physics and Chemistry of Rare Earths contains four chapters (Chapters 165 - 168 in the series) that continue the quest of the Handbook series: to provide answers to fundamental questions regarding physical and chemical properties of rare earth metals, alloys and compounds. These elements have played a key role in developing the theories of electronic structure, magnetic properties and spectroscopy, which are central to the development of physics and chemistry. Through this aim, the contributing authors of Volume 25 have enriched the fields of earth science, biological science, and medicine via the extraordinary properties inherent in these materials. The first chapter "Rare earths in steels" introduces the reader by explaining how rare earths were used in the steel industry since the early 1920’s to affect deoxidation and desulfurization. More modern uses utilize rare earths to provide steels with specific characteristics such as designed thermodynamics, shape control, mechanical properties, directionality, grain refinement, and structure. The chapter also covers hydrogen embrittlement, the effect of rare earths on hydrogen-induced delayed failure, stress corrosion cracking, permeability in steels, powder metallurgy, creep behavior, and welding. The second chapter "Ternary and higher order nitride materials" reviews the synthesis of ternary rare earth nitrides and covers the properties of ternary nitrides and oxynitrides, including Li2CeN2, Ce2N2O, BaCeN2, BaCeR(O,N)4, and PrBN2, Ce3B2N4, and Ce15B8N25-type boronitrides. The Y-Zr-O-N system is also reviewed. The following chapter "Spectral intensities of f - f transitions" discusses the unique appearance of intraconfigurational electronic transitions in f –type lanthanides. Transition mechanisms, intensity theory, magnetic dipole transitions, Judd-Ofelt theory, intensity parameterization of transitions between crystal-field levels and J - multiplets, hypersensitivity, vibronic transitions, two-photon spectra, and the color of lanthanide ions are reviewed. The final chapter "Organometallic p complexes of the f -elements" reviews the available literature on the main classes of complexes of both the lanthanide and actinide organometallics, and the preparation and structure of these compounds are discussed. Volume 25 of the 492-page hardcover Handbook was published in 1998 and is available for US$227.00/NLG395.00 by contacting Elsevier Science, P.O. Box 211, 1000 AE Amsterdam, the Netherlands; Tel: 31 20 485 3757; Fax: 31 20 485 3432; nlinfo-f@elsevier.nl; www.elsevier.nl. The NATO Science Program Advanced Study Institute (NATO ASI) will serve as a forum for discussing fundamental issues in the field of magnetostriction phenomena and the principles of their applications in various disciplines of science and technology. The conference "Modern Trends in Magnetostriction Study and Application" will include lectures, progress reports and poster presentations that cover the new developments that relate to both fundamental and practical applications involving magnetostriction phenomena. The conference will be held in Crimea, Ukraine in May, 2000. Topics of the conference will include: general introduction to modern trends in magnetostriction study and application, theory of magnetostriction and related phenomena, rare earth magnetostriction study and application, magnetostriction of amorphous materials, giant magnetostriction in superconductors, GMR materials, structural study of magnetostriction, industrial applications, and magnetostriction of nanostructure materials. For more information, contact the Institute for Low Temperature Physics & Engineering, 47, Lenin Ave., 310164, Kharkov, Ukraine; Tel: 380 572 321 223; Fax: 380 572 322 370/380 572 335 593; ASI-2000@ilt.kharkov.ua. The IV Latin American Workshop on Magnetism, Magnetic Materials and Their Applications was held in São Paulo, Brazil, June 7-11, 1998. Most of the 111 participants of the workshop were researchers from Brazil, however, many Latin American countries were represented, Argentina, Colombia, Mexico, Cuba, Peru, and Venezuela. The topics covered at the workshop included thin films, giant magnetoresistance, magnetoimpedance, nanocrystalline materials, superconducting oxides, magneto-optics, and others. Rare earthers will be primarily interested in the sections concerning the neutron diffraction studies of magnetic materials and reduced dimension systems, structural and magnetic properties of Sm/Fe thin films, light-emitting diode based transverse magneto-optical Kerr effect, and colossal magnetoresistance in rare earth manganites (primarily (La,Ca)MnO3, and (R,Ce)2CuO4, (Eu,Pr)CuO4, and (La,Sr)Cu. The highest number of rare earth papers are contained in the section "Hard Magnets" and cover the topics of nanocrystalline Nd2Fe14B-a Fe composites, flash annealed PrFeB, hybrid magnets, magnetic properties and spectroscopic studies of magnetic rare earth alloys, the HDDR process of Nd-Fe-B alloys, and magnetic properties of Sm2Fe17Nx. The contributions concerning low temperature magnetism include (La,Pr)BaCuO5Fe, magnetic ordering in TbNi5, and the physical properties in (Ce,La)Fe2Ge2, and devices based on first order magnetic phase transition of (R1-xR’x)Co2 pseudo-binary compounds. Two contributions on fluids and particles include magnetic 3d impurities in a hexagonal close-packed iron host, and the electrochemical behavior of magnetic materials in various solutions. The 85 contributions are contained in the 499-page soft cover book entitled "Magnetism, Magnetic Materials and Their Applications" and was published in Materials Science Forum Volumes 302-303 in 1999. The cost of the book is US$174.00/£98.00/CHF235.00 and can be ordered from Trans Tech Publications Ltd., Brandrain 6, CH-8707 Uetikon-Zurich, Switzerland; Fax: 41 1 922 10 33; www.ttp.net. The Net Shape Laboratory at the University of Birmingham, UK, has begun operations to develop production procedures of "ready to go" Nd-Fe-B permanent magnets {Magnews, Spring, p. 10 (1999)}. Customer demands for rare earth permanent magnet materials that need minimal forming and machining are increasing the demand for the industry to "net shape" permanent magnets. Currently, Nd-Fe-B magnets are produced by a powder sintering route that uses hydrogen to decrepitate the bulk material (the HD and HDDR processes). This manufacturing procedure involves a substantial change in the structural volume of the material as it transitions from the compact to the final magnet. To meet the customers’ specifications, the magnet must then be machined, which not only takes additional resources, but produces waste materials that must be recycled or disposed of properly. These final production stages are responsible for up to half of the production costs involved in Nd-Fe-B magnets. However, the two disadvantages of net shaping includes a lower energy product because the material is diluted by the binding polymer, and decreased corrosion resistance, particularly in warm and humid environments. The methods to produce economically-feasible net shaped rare earth permanent magnet materials is the goal of the Net Shape Laboratory through research and development. The investigations will include hot pressing of bulk alloys and of HD and HDDR powdered alloys. This also includes solidification trials on the bulk material using advanced foundry facilities. Anisotropic HDDR powders are used in the hot pressing trials and in the production of anisotropic polymer bonded magnets. A range of processing parameters are also investigated in order to optimize production of these magnets, including process modeling. For more information, contact Dave Brown, Department of Metallurgy & Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; Tel: 44 121 414 5213; Fax: 44 121 414 5247; d.n.brown@bham.ac.uk. A review by J.M.D. Coey, Physics Department, Trinity College, Dublin 2, Ireland, et al. {Adv. Phys., 48, [2], 167-293 (1999)} covers the state of our understanding of mixed-valence manganese oxides (R1-xAx)MnO3 (R= rare earth cation, A= alkaline or alkaline earth cation), and other magnetic semiconductors. These rare earth perovskites display a variety of crystallographic, electronic and magnetic phases and exhibit a phenomena such as colossal magnetoresistance near the Curie temperature, dense granular magnetoresistance and optically-induced magnetic phase transitions. The authors address the nature of the electronic ground states, the metal-insulator transition as a function of temperature, pressure and applied magnetic field, the electronic transport mechanism, dielectric and magnetic polaron formation, magnetic localization, the role of cation disorder and the Jahn-Teller effect. Sample preparation and the properties of related ferromagnetic oxides are also discussed. A discussion of Eu chalcogenides (EuO, EuS, EuSe, and EuTe) magnetic semiconductors includes influence of carriers on magnetic properties, and transport and related phenomena. Although the magnetic structures and magnetic properties of (La,Ca)MnO3 and (Pr,Ca)MnO3 are somewhat similar, their electronic structures are quite different. The authors provide some insight into this situation by explaining that for a ferromagnetic phase for x =0.3 in (La1-xCax)MnO3 and for x closer to 0.2 in (Pr1-xCax)MnO3, it does not have the high conductivity associated with ferromagnetism in a cubic or rhombohedral phase. The transport properties are also different, as are structural details such as the Mn-O-Mn bond angle for the double exchange mechanism. For anyone currently working with these compounds, or students needing a solid background in rare earth perovskite manganites, Mixed-valence manganites deserves a read. New Inorganic Scintillators and Storage Phosphors for Detection of Thermal Neutrons is a 180-page soft cover book that reviews the current level of knowledge related to neutron detector technology. The focus is on inorganic scintillator and storage phosphor materials, however, new materials have been studied and their potential for application in detectors has been considered.The mechanisms of storage phosphors and scintillators are shared in that they convert ionizing radiation into visible light while storing a portion of their energy. Free electrons and holes created by radiation absorption do not readily recombine, but are separately trapped at impurity or defect sites in the material, which is liberated via optical stimulation. The recombination of the electrons and holes can then occur. The book, authored by Mathijs Knitel, deals with the subject in 8 sections. Following a brief introduction, thermal neutron detection methods are presented, including the 155Gd and 157Gd reaction (neutron capture methods), and counting detectors (scintillators), and integrating detectors; selection of materials, radiation sensitivity and decay times, and the scintillator Eu-doped BaFBr; LiBaF3 as a thermal neutron scintillator; scintillation and storage properties of LiYSiO4:Ce and LiLuSiO4:Ce; photoluminescence in Eu2+ and Ce3+ borates; thermal neutron image plates using Eu2+ activated M2B5O9X (M=Ca, Sr, Ba; X=Cl, Br); and the recombination of charge carriers in the haloborate Sr2B5O9Br:Eu2+. New Inorganic Scintillators and Storage Phosphors for Detection of Thermal Neutrons is published in 1998 by Delft University Press, Mekelweg 4, 2628 CD Delft, The Netherlands; Tel: 31 15 278 3254; Fax: 31 15 278 1661; dup@dup.tudelft.nl. Neomet Corporation closed their doors for business May 31, 1999 and were purchased by International Specialty Alloys (I.S.A.) on June 1, 1999. For more information, contact Joseph Patrick, President, International Specialty Alloys, P.O. Box 428, Edinburg, PA 16116 USA; Tel: 724 667 3003; Fax: 724 667 3002. Join-Line Industries Inc. is a company that is involved in the recycling and recovery of Nd-Fe-B and Ni-Metal Hydride alloys. The recovered Neodymium Oxide and Dysprosium Oxide are then processed into Neodymium and Dysprosium metal that are claimed to meet the specifications of Nd-Fe-B and Ni-Metal Hydride alloy producers. Join-Line will purchase waste materials for recycling, and will offer materials for the production of Nd-Fe-B permanent magnets and NiMH batteries. Contact Mindele Chan, Join-Line Industries Inc., 11D, Blue Building, Yenzo Holiday Resort, High Tech Industrial Development Zone, Changsha, Hunan, People’s Republic of China; Tel: 86 731 8806188; Fax: 86 731 8805988; joinline@public.cs.hn.cn. Intertech Corp., the rare earth consulting, conferences & studies company, has moved. Their new address is: 19 Northbrook Drive, Portland, ME 04105 USA; Tel: 207 781 9800; Fax: 207 781 2150; info@intertechusa.com; www.intertechusa.com. Ferro Electronic Materials is the new name for the company formerly known as the Transelco Division of Ferro Corporation. For more information, contact G. Braun, Ferro Electronic Materials, 1789 Transelco Drive, Penn Yan, NY 14527 USA; Tel: 315 536 3357; Fax: 315 536 8091; www.ferro.com. Atlantic Metals & Alloys, Inc. has moved. Their new address is 355 Benton Street, P.O. Box 589, Stratford, CT 06615-0589 USA; Tel: 203 378 9025; Fax: 203 378 9570. Santoku America, Inc., has opened an office in a Chicago suburb. Their new address is: Two Continental Towers, 1701 Golf Road, Suite 605, Rolling Meadows, IL 60008 USA; Tel: 847 437 5520; Fax: 847 437 5521. In the highly competitive sport motorcycle market, manufacturers strive to improve performance of their products on a continual basis. The major areas that provide the most immediate positive result on a motorcycle are improvement in handling, power increase, and weight reduction. The Kawasaki Motor Company (www.kawasaki.com) has made a significant reduction in weight on its 899cc Ninja engine by making it 20 pounds lighter. To achieve this, Kawasaki's engineers completely redesigned the engine, learning more than a thing or two from their last ground-up powerplant upgrade on smaller engine model. One of the improvements that made the weight loss possible was replacing its chain-driven alternator with a Neodymium-Iron-Boron magnet unit that is attached directly to the end of the crankshaft. Other design changes also contribute to the weight loss, such as using aluminum-magnesium alloys in the engine and replacing a "new" hydraulic actuator with an "older" cable operated unit. Power has always been the big Ninja’s strong suit and continues be so, as Kawasaki claims these improvements provide for four more horsepower measured at the crankshaft. Lowered rotating engine mass coupled with decreased weight makes for a higher-revving engine and quicker throttle response. The Dubbo Rare Metal Project will mine and extract minerals from the Toongi deposit, which is located about 400 km northwest of Sydney, New South Wales, Australia. The project is centered between the towns of Dubbo and Peak Hill and lies in the Lachlan Fold Belt, which has been identified to contain anomolous concentrations of niobium, zirconium, hafnium, and rare earths. The hydrothermally altered volcanic rock is in an elliptical band and covers approximately 185,000 m2. The intrusive minerals in the Toongi deposit consist of fine grained alkali rocks made up of potassic feldspars, albite and aegerine with carbonate, accessory quartz and the ore minerals. The ore minerals are categorized in four major groups: 1) Zirconium – zirconium silicate with calcium, yttrium, and rare earth elements; 2) Yttrium – occurring as silicates with other rare earths; 3) Niobium/Tantalum minerals, and; 4) Rare earth-containing bastnasite. Surveys indicate a resource of 10 million mt grading 0.12% Y2O3, and 0.75% rare earth oxides. The deposit may also contain another 40 million mt at similar grades for a total of 50 million mt. Recent mapping has discovered that the intrusive body is covered by a shallow sedimentary cover and suggests, that if mined, the figure could double to 100 million mt. Extractive metallurgy of the rare earth minerals will include crushing, grinding, sulfuric acid leach, solvent extraction and refining, and selective precipitation. Sulfuric acid leach appears to be the key step in processing since the mineral ore species present since much of the host rock is insoluble to the sulfuric acid, which will limit acid consumption while restricting the volume of elements in solution. Development of the deposit and commercialization of rare earth products is possible in 2000-2001. Contact Alkane Exploration NL, 129 Edward Street, Perth WA 6000, Australia; Tel: 618 9227 5677; Fax: 618 9227 8178; www.alkane.com.au. Advanced Aluminum Alloys Containing Scandium deals with the structure and properties of binary Scandium-aluminum alloys and more complex Sc-Al alloys also containing transition metals. The book also includes a thorough analysis of the reference data available and is an attempt to generalize and analyze the extensive experimental and theoretical work on Sc-Al alloys performed by researchers in the field. The effects of scandium on the phase composition, structure, phase transformations and properties of aluminum alloys are considered from the perspective of physicochemical analysis. Phase diagrams of Scandium-aluminum binary, ternary, and multi-component alloys are considered in detail, as are the effects of solidification conditions on phase equilibria, recrystallization, superplastic behavior, and decomposition of supersaturated solid solutions. Based on the quantitative analysis of their structure and properties, the microstructure stability for these aluminum alloys are determined by various calculations. The interrelation between the structure and properties of Sc-Al alloys with different phase compositions and the hardening mechanisms are discussed. Some practical recommendations are provided for alloying aluminum alloys with Scandium by leading researchers in this field. The ternary Sc-Al-TM alloys covered include Cu, Fe, Mg, Mn, Si, and Zr. The more complex alloys include (Sc-Al-Mg-Si-Zr), (Sc-Al-Li-Mg), and (Sc-Al-Mg-Zn). The development of commercial aluminum alloys for large-scale welded structures that are used to support heavy loads were dependent on the experimental results, along with the available reference data, compiled by the contributors of this book. Aluminum alloys are also used in corrosive media and alloys exposed to irradiation. Advanced Aluminum Alloys Containing Scandium Structure and Properties is authored by L.S. Toropova, D.G. Eskin, M.L. Kharakterova, and T.V. Dobatkina, and was published in 1998. The 175-page hard cover book is available for US$75.00 through Gordon and Breach Science Publishers, PTT, P.O. Box 566, Williston, VT 05495-0566 USA. Strongest
Magnet The magnetic properties of the new magnet were gained by a combination of reducing the nonmagnetic phase of the grain boundaries, increasing the polycrystalline orientation to approximately 98% alignment and density to 99%. This was accomplished by improving the precision control of the sintering process. Commercial production of the new magnet is scheduled for next year but the mass produced magnet is planned to have a magnetic strength of 53 MGOe. Applications for the new magnet is expected to be in small electric motors for computer disk drives, magnetic resonance imaging equipment, and motors for hybrid-electric automobiles. Sumitomo Special Metals Company Ltd., No.3 Sumitomo Bldg., 4-7-19 Kitahama, Chuo-ku Osaka 541-0041, Japan ; Tel: 06 6220 8822; Fax: 06 6220 8909; www.ssmc.co.jp. Thermoelectric
Power The new thermoelectric element uses Na-Co oxide on the p-side, and Nd-Cu oxide (with Zr added) on the n-side. It shows an increased heat resistance over the metal elements, which allows the devices to be operated at higher temperatures. This allows an increase in temperature differential, which boosts the efficiency of electric power generation. The new device generates 280 mV using a temperature difference of 200°C. Another advantage of the oxide elements is that they can be used in an ordinary atmosphere with out degradation. Tokyo Gas Company Ltd., 1-5-20 Kaigan, Minato-ku, Tokyo 105, Japan; Tel: 03 3433 2111; Fax: 03 8437 9190. Lanthanum Gallium Oxide for
Fuel Cells Current ceramic fuel cells generate 0.2 W at a temperature of about 1000°C, whereas the Lanthanum Gallium Oxide material produced 0.4 W/m-2, sufficient for practical applications. This may be explained by the fact that the lanthanum electrolyte allows an increase in the flow of oxygen as compared with the yttria-stabilized zirconia solid electrolyte material. For more information, contact: Oita Faculty of Engineering, Oita University, 700 Dannoharu, Oita 870, Japan; Tel: 0975 54 7752; Fax: 0975 54 7760. Consultant’s Corner To appear in our Consultant’s Corner, any individual, company, or group must be involved in rare earth or rare earth-related consulting activities. Just send us the appropriate information: contact name, company name, mailing address, Tel/Fax number(s), e-mail and web address, and areas of expertise.
Yttria-stabilized zirconia (Y2O3-ZrO2) has been well known as a ceramic coating on components that are used in powerful and efficient engines which are subject to high temperatures. These thermal barrier coatings extend the operating life cycle of metal engine parts by protecting them from the rigors of extreme temperatures. The National Institute of Standards and Technology (NIST) is conducting research on the microscopic behavior of YSZ coatings to determine how their microstructures change when subjected to extreme temperatures inside these engines. It had been previously thought that ceramic microstructures do not change until within 50% of their melting point. However, NIST has discovered that YSZ microstructures change after being heated to only 800° C, which is far lower that zirconia’s melting point of 2750° C. The researchers are hoping that new information on the microstructure study on YSZ will lead to improved coatings for engines. Emil Venere, NIST, Gaithersburg, MD 20899 USA; Tel: 301 975 5745; emil.venere@nist.gov; www.nist.gov. Since the June issue of the RIC News went to press, we have received support from one new family members and renewed support from 31 other organizations. The supporters from the fourth quarter of the 1999 fiscal year who wish to be listed, grouped according to their appropriate category, and with the number of years that they have contributed to RIC in parenthesis, are listed in the next column. Benefactor ($10,000 or more) Donor ($4000 to $9999) Sponsor ($2000 to $3999) Patron ($1000 to $1999) Sustaining ($400 to $999) Contributor (less than $400) |top of page| |Home Page| |TitlePage| |Issues on Web| |Sponsors| |