Functionally Graded Tantalum/Niobium Carbide Materials

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FUNCTIONALLY GRADED TANTALUM/NIOBIUM CARBIDE MATERIALS Ceramic material with improved strength, durability, hardness, and fracture toughness for use in high temperature and/or corrosive applications. TECHNOLOGY SUMMARY TECHNOLOGY TYPE Hard materials resist wear, but are prone to fracture. Tough materials Ceramics resist fracture, but are susceptible to wear. Ideally, a material should Metallurgy possess a combination of high hardness and high fracture toughness, Material Science but designing such a material has proven difficult. A novel tantalum or STAGE OF DEVELOPMENT niobium carbide (TaC or NbC) results in a composite with superior - Early stage TaC prototype strength and fracture toughness. The material consists of two-phases, a demonstrated for certain wear hard carbide on the outside and a tough carbide in the interior. The applications and carbide substrate can be produced using conventional powder manufacturing process. processing methods to fabricate complex shapes and surface-treatment. - Novel nobium carbide The proposed material outperforms tungsten carbide in applications ceramic testing in process. that require hardness, fracture toughness, and corrosion resistance. IP PROTECTION FEATURES AND BENEFITS Nationalized PCT Issued in • Provides durable material that is suitable for high-temperature and the United States high-pressure applications. High-Toughness Zeta-Phase • Increases strength, hardness, and fracture toughness by up to three Carbides times that of Tungsten Carbide US8685874B2 • Able to manufacture components from a single piece of material. US Utility Patent Issued Methods of Sintering Dense Zeta-Phase Tantalum Carbide RECENT PUBLICATIONS US9896384B2 Meeks, G.J., Dalton, J.S., Sparks, T.D., Shetty, D.K. (2015). A functionally Additional Patent Pending in graded carbide in the Ta-C system. Journal of the American Ceramic Society. the United States and China 99(2):392-394. doi: 10.1111/jace.14045 Sygnatowicz, M., Cutler, R.A., Shetty, D.K. (2015). Ta4C3-x: A high fracture toughness carbide with rising- LEARN MORE crack-growth-resistance (r-curve) behavior. Journal of the American Reference Numbers: U-4451, Ceramic Society. U-5794, U-5881 Nick Wilkes INVENTOR PROFILE Technology Manager Dinesh K. Shetty, Ph.D., Professor - Materials Science and Engineering [email protected] Raymond A. Cutler, Ph.D., Adjunct Professor - Materials Science and 801-587-0515 Engineering DATE UPDATED: 1/22/2018 .

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Sintering of Niobium Containing AISI M2 High Speed Steel
Sintering of AISI M2 high speed steel with the addition of NbC Alexandre Wentzcovitch1, Francisco Ambrozio Filho1, Luis Carlos Elias da Silva2, Maurício David Martins das Neves2 1Centro Universitário da FEI 2Instituto de Pesquisas Energéticas e Nucleares – IPEN-CNEN/SP [email protected]; [email protected]; [email protected]; [email protected] Keywords: powder metallurgy, high speed steel, NbC, sintering and microstructure. Abstract. The influence of adding 6 wt% (NbC) niobium carbide on the sintering temperature and microstructure of high speed steel - AISI M2 (0.87% C, 5.00% Mo, 6.00% W, 4,00% Cr, 2.00% V and Fe bal.) powder was studied. The starting material was obtained by vacuum melting followed by atomization in water. The samples were axially cold compacted in a cylindrical matrix and then vacuum sintered at 1250 and 1350 °C. Dilatometry and differential scanning calorimetry measurements indicated an increase in sintering temperature with addition of niobium to the AISI M2 steel. Optical and scanning electron microscope observations revealed a microstructure with uniformly distributed niobium carbides. Introduction High-speed steels have been widely used in the manufacture of cutting tools and wear-resistant materials [1]. Several techniques have been used to improve the properties of sintered high speed steels and these include: addition of alloying elements to increase carbide formation [2, 3], addition of ceramic reinforcements and use of high- energy milling [4]. Niobium is an alloying element that can be added to high speed steels to form stable carbides and provide reinforcement to the matrix. The niobium added to the steel combines with carbon to form a MC-type carbide, which can increase the hardness and wear resistance of the high speed steel and prevent austenite grain growth during sintering and heat treatment.
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Evaluation of Anticorrosive Effect of Niobium Carbide Coating
1387 A publication of CHEMICAL ENGINEERING TRANSACTIONS VOL. 57, 2017 The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Sauro Pierucci, Jiří Jaromír Klemeš, Laura Piazza, Serafim Bakalis Copyright © 2017, AIDIC Servizi S.r.l. DOI: 10.3303/CET1757232 ISBN 978-88-95608- 48-8; ISSN 2283-9216 Evaluation of Anticorrosive Effect of Niobium Carbide Coating Applied on Carbon Steel b a b a Luisa Novoa , Luis E. Cortes , Eliana Gonzalez , Arnaldo Jimenez , Luis G. a a a Cortes , Mario Ojeda , Aida L. Barbosa* a Laboratory of Research of Catalysis and New materials (LICATUC), Science Faculty, Chemistry Program, University of Cartagena, Campus of Zaragocilla, Kra 50 Nº 30-40, Cartagena, Colombia b Dept of Civil Engineering, Civil Enginering programm, University of Cartagena, Campus of Piedra de Bolivar, Av. El Consulado Calle 30. No. 48 - 152, Cartagena, Colombia [email protected] South America and particularly Colombia, has niobium and tantalum deposits, which can be used as a carbon steel protective agent. A preliminary step is the raw material characterization. Fresh and calcinated samples of niobium mineral in ores and sand were analyzed through optic microscopy, laser-Raman spectroscopy, DRX and textural aspects. The main components of the ore and alluvial sand were Ferrotapiolite and ferrocolumbite with chemical formula (Fe,Mn)•(Ta,Nb)2O6 and associated oxides like Fe2O3, SiO2. In the shape of Tectosilicates, Mn-Tantalite, Nb=O terminal and polyatomic octahedral structures of NbO6, highly distorted, susceptible to form carbides. Ferrocolumbite synthetic (FeNb50) was used as precursor of NbC coating for the surfaces protection of AISI 1020 steel samples having dimensions of 3/8 inch diameter and 1/2 inch length.
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Technology Properties and Applications of Niobium Carbide
Fundame slatn and Applications of Mo and Nb Alloying in High Performance sleetS – Volume 2 Edited by Hardy Mohrb ehca r CBMM, IMOA and TMS, 2015 TECHNOLOGY, PROPERTIES AND APPLICATIONS OF NIOBIUM CARBIDE REINFORCED STEEL AND IRON ALLOYS H. Mohrb ca h re 1 a dn D . Jar er at 2 1 NiobelCon bvba, Schild ,e B le gium 2 Metal Prime T ce olonh gy .etP L ,.dt niS g pa ore Keywords: Abrasive eW ,ra Wear Resistant Steels, NbC Particles, W etih C tsa I nor s Abstract The al rge tsoc dna snoc i elbared downtime uac es d by lper a ic ng wo nr rap ts ni htrae moving na d mining equipment, sa well sa ni eht materials issecorp ng tsudni ry, er stneserp a uounitnoc s ellahc nge ot materi la poleved men .t Components sed ig den rof sacri cif i la wear must ni ht e tsrif ecalp ssessop tauqeda e a noisarb natsiser c .e F qer u tne ly, oh wev ,re ht ey must osla evah ht e iliba ty ot dnatshtiw impact dna to tsiser chemical .kcatta The eriuqer m tne fo good noisarba r ecnatsise in combination htiw g oo d uot g ssenh si g ne e lar ly ni .noitcidartnoc Typi lac ly, rah d ori n- esab d materials hcus sa marten etis ro etirubedel era hi hg ly tnatsiser ot ba r isa on, y te very elttirb dna tluciffid ot machine. An evitavonni rppa o hca si ot compose a more cud tile ori n-b desa m irta x, embedding a much ah r red we ra tnatsiser phas .e Amongst esoht ex rt emely ha dr ahp s se are sedibrac of eht tr noitisna metals uinatit m, oin b ui m, dna ut ng ets n tiw h hardn sse fo vo er 002 0 HV.
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Development of Niobium Powder Injection Molding. Part II: Debinding and Sintering
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FS&T Template
ANS NETS 2018 – Nuclear and Emerging Technologies for Space Las Vegas, NV, February 26 – March 1, 2018, on CD-ROM, American Nuclear Society, LaGrange Park, IL (2018) STUDY OF A TRICARBIDE GROOVED RING FUEL ELEMENT FOR NUCLEAR THERMAL PROPULSION Brian Taylor1, Dr. Bill Emrich1, Dr. Dennis Tucker1, Marvin Barnes1, Nicolas Donders2, and Kelsa Benensky3 1NASA Marshall Space Flight Center, Huntsville, AL, 35812 2Kettering University, Flint, MI, 48504 3University of Tennessee, Knoxville, TN, 37996 Deep space exploration, especially that of Mars, is flow passages through which propellant was flowed. The on the horizon as the next big challenge for space nuclear fission reactions heated the material in the rod and exploration. Nuclear propulsion, through which high the heat was transferred to the propellant. This type of thrust and efficiency can be achieved, is a promising nuclear propulsion is called nuclear thermal propulsion option for decreasing the cost and logistics of such a (NTP). Later, particle bed reactors were considered in a mission. Work on nuclear thermal engines goes back to defense project called Timberwind. This reactor the days of the NERVA program. Currently, nuclear geometry flowed propellant through a bed of spherical thermal propulsion is under development again in various fuel “particles” to greatly increase surface area and thus forms to provide a superior propulsion system for deep heat transfer. This design showed promise for space exploration. The authors have been working to significantly improving thrust to weight ratios and develop a concept nuclear thermal engine that uses a specific impulse compared to the NERVA engines. It grooved ring fuel element as an alternative to the suffered; however, from nuclear thermal instabilities.2 traditional hexagonal rod design.
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ATOMIC Bnbstav V
I ATOMIC BNBStaV v: •M i rr ' UP", +**z B.A.R.C.-612 GOVfiRNMENf OF INDIA ATOMIC ENERGY COMMISSION PREPARATION OF ZIRCONIUM-NIOBIUM ALLOY PRE ^YACARBIDE-OXIDE REACTIONS by R. ViiAatltanjant, S.P. Garg and C.V. Sundaram ;• - Metallurgy Division BHABHA ATOMIC RESEARCH CENTRE BOMBAY, INDIA 1972 ABSTRACT This investigation is concerned with thedirect preparation of Zr-Nb master alloys by reaction between ZrC and Nb2Os. The thermo- dynamics of the reaction are discussed. Starting with 2 different composi- tion* corresponding to 5% and 15$ excess oxygen over the stoichiometric requirements, and adopting progressive heat-soaking under high dynamic vacuum, followed by electron beam melting, sirconium-niobium alloys low in carbon and oxygen have been prepared. The influence of initial oxygen excess and time of heat soak on the final purity of the alloy has been examined. The overall material balance for the reaction indicates removal of oxygen both through carbothermic reduction (as CO) and through sacrificial deoxidation (as ZrO). PREPARATION OF ZIRCONIUM-NIOBIUM ALLOY BY CARBIDE-OXIDE REACTIONS by R. Venkataramani, S, P. Garg and C.V. Sundaram the beneficial effects due to the alloying addition of niobium on the mecKanical properties and the corrosion resistance of zirconium have been extensively discussed in thj literature/1'2'3) A Zr-2. 5% Nb alloy Is re- yovUd2) to be preferred to zircaloy for the permanent structural compo- nents - such as coolant tubes - in pressurized water nuclear reactors. the present investigation has been concerned with the direct pre- |araltibn of Zx-Nb master alloys by carbo-thermic reduction reacHons.
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