Увійти

Готові списки джерел за темами / High Niobium / Статті в журналах

Статті в журналах з теми "High Niobium"

Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: High Niobium.

Автор: Grafiati

Опубліковано: 14 березня 2023

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся з топ-50 статей у журналах для дослідження на тему "High Niobium".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.

1

Papulovskiy, Evgeny, Aleksandr Shubin, and Olga Lapina. "Theoretical Modeling Of The Structure Of Surface Niobium Sites Based On Solid-State 93nb Nmr." Siberian Journal of Physics 11, no. 2 (June 1, 2016): 77–91. http://dx.doi.org/10.54362/1818-7919-2016-11-2-77-91.

Повний текст джерела

Анотація:

In this work niobium oxide clusters on the surface of Al2O3 are modeled using DFT calculations. 93Nb NMR parameters of modeled clusters were computed with the GIPAW method. The niobia system under consideration represents high niobium loading on the surface of the support. The niobium atoms are highly coordinated and linked to the other niobia polyhedra by one or two bonds. The most of the niobium oxide particles has a coordination number of six. The correlations found between 93Nb NMR parameters and coordination environment are discussed.

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Tolosa, Aura, Benjamin Krüner, Simon Fleischmann, Nicolas Jäckel, Marco Zeiger, Mesut Aslan, Ingrid Grobelsek, and Volker Presser. "Niobium carbide nanofibers as a versatile precursor for high power supercapacitor and high energy battery electrodes." Journal of Materials Chemistry A 4, no. 41 (2016): 16003–16. http://dx.doi.org/10.1039/c6ta06224e.

Повний текст джерела

Анотація:

Electrospun niobium carbide/carbon nanofibers are a facile precursor to derive highly nanoporous carbide-derived carbon for supercapacitor applications, or niobium pentoxide/carbon for battery electrodes.

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Montheillet, Frank, S. Girard, Christophe Desrayaud, S. Lee Semiatin, and J. Le Coze. "Hot Working of High-Purity Nickel-Niobium Alloys." Materials Science Forum 539-543 (March 2007): 2966–71. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.2966.

Повний текст джерела

Анотація:

The present work deals with the influence of niobium in solid solution on the dynamic recrystallization of pure nickel. High-purity nickel and two model nickel-niobium alloys were deformed to large strains via torsion at temperatures between 800 and 1000°C. Niobium additions considerably increased the flow stress, while they lowered the strain-rate sensitivity and increased the apparent activation energy. EBSD of the steady-state microstructures revealed strong grain refinement. Substructure development was favored, whereas thermal twinning was reduced by niobium. More generally, discontinuous recrystallization kinetics were considerably decreased.

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Sakaki, Hayato, Masayuki Mizumoto, Takeshi Ohgai, and Akio Kagawa. "New Application of High Niobium Cast Iron as a Grain Refiner for Stainless Steels." Key Engineering Materials 457 (December 2010): 447–52. http://dx.doi.org/10.4028/www.scientific.net/kem.457.447.

Повний текст джерела

Анотація:

In order to develop a new application of cast iron, high niobium cast iron has been developed as a grain refiner for stainless steel. High niobium cast iron was prepared by adding pure niobium to a commercial cast iron. Coarse primary niobium carbide crystals were observed in the microstructure of the cast iron. The effect of the high niobium cast iron as an inoculant on the grain size of austenitic and ferritic stainless steels was examined in various experimental conditions. When the amount of the cast iron inoculant more than 3 mass% was added into the steel melt, fine equiaxed grains were observed and grain size was significantly reduced to 210 μm. The results indicate that the high niobium cast iron is effective as a grain refiner for the austenitic and ferritic stainless steels. From the dissolution rate measurement, the grain refining mechanism was proposed.

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Alias, Siti Khadijah, Bulan Abdullah, Ahmed Jaffar, Abdul Hakim Abdullah, and Norhisyam Jenal. "Development of High Strength Ductile Iron with Niobium Addition." Advanced Materials Research 576 (October 2012): 366–69. http://dx.doi.org/10.4028/www.scientific.net/amr.576.366.

Повний текст джерела

Анотація:

The studies emphasis on the development of niobium alloyed ductile iron with higher strength comparing to unalloyed ductile iron. 0.5wt% to 2wt% niobium were added into mixture of ductile iron casting containing pig iron, carburizer and steel scrap, and nodulized through 1.6wt% Fe-Si-Mg addition in CO2 sand casting process. Samples were then machined according to TS EN 10001 standards for tensile test and ASTM E23 for Charpy impact test. In addition, Rockwell hardness test was also performed. Microstructure observations were made after 2% Nital chemical etched and the phase structures were validated through XRD analysis. It was found that addition of niobium in ductile iron provide significant enhancement in mechanical properties when compared to unalloyed ductile iron. Addition of higher amount of niobium had further increased the strength and impact toughness properties. The enhancement of the mechanical properties is expected to further expand the applications of ductile iron.

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Gupta, C. K., D. K. Bose, and N. Krishnamurthy. "Preparation of high purity niobium." Journal of the Less Common Metals 139, no. 1 (April 1988): 189–202. http://dx.doi.org/10.1016/0022-5088(88)90341-4.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Shyrokov, Volodymyr V., Orest S. Tcvikilevitch, and Chrystyna B. Vasyliv. "Stability of strengthened niobium alloys in long-term high-temperature loading conditions." International Journal of Materials Research 93, no. 11 (November 1, 2002): 1123–31. http://dx.doi.org/10.1515/ijmr-2002-0193.

Повний текст джерела

Анотація:

Abstract Variations in structure and heat resistance of niobium alloys after long-term loading (for up to 10 000 h) in vacuum at 1173 and 1373 K are studied. It is concluded that niobium alloys are more heat-resistant while those undergoing solid-solution hardening are more stable structurally. It is shown that long-term strength plots for niobium alloys have kinks which are to be taken into account when predicting life of structurally unstable materials.

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Musenich, R., P. Fabbricatore, G. Gemme, R. Parodi, M. Viviani, B. Zhang, V. Buscaglia, and C. Bottino. "Growth of niobium nitrides by nitrogen-niobium reaction at high temperature." Journal of Alloys and Compounds 209, no. 1-2 (July 1994): 319–28. http://dx.doi.org/10.1016/0925-8388(94)91120-7.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Cheng, Shi Chang, Zheng Dong Liu, Zhao Jie Lin, and Han Sheng Bao. "Effect of Niobium Content on Laminar Precipitate and High Temperature Mechanical Properties of 21-2N Valve Steel." Materials Science Forum 654-656 (June 2010): 182–85. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.182.

Повний текст джерела

Анотація:

Effect of niobium content on laminar precipitate and high temperature mechanical properties of 21-2N vavle steel was systematically studied, using specimens contain 0.26%, 0.43%, 0.65% 0.82% and 1.06% Nb. After different solid solution treatment and 750 °C aging heat treatment, experimental results showed that laminar precipitate was suppressed by niobium addition, and with the increasing of niobium content, laminar precipitate content decreased and size, distribution and morphology of laminar precipitate was meliorated. Then creep rupture strength and fatigue strength of experimental steels are improved with increasing of niobium.

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Kitamura, Naoyuki, Kohei Fukumi, Kenji Kintaka, Hironori Ofuchi, Tetsuo Honma, and Tomoko Akai. "Development and Precision Molding of Optical Glasses with High Refractive Index for Optical Applications." Key Engineering Materials 702 (July 2016): 96–100. http://dx.doi.org/10.4028/www.scientific.net/kem.702.96.

Повний текст джерела

Анотація:

The structure and optical properties of phosphate glasses containing bismuth or niobium oxides for subwavelength structure (SWS) optical elements were studied. The glasses containing a large amount of bismuth and niobium oxides had refractive indexes higher than 1.8 and low deformation temperatures. However, these high refractive index glasses were yellowish due to the electronic transition in trivalent bismuth ions and pentavalent niobium ions. The structure of the glasses was investigated by X-ray, IR, and Raman spectroscopy. NbOx and BiOx formed clusters as the bismuth and niobium oxide content increased. The results showed that the local structure around bismuth and niobium ions was related to the coloration. Based on these results, we developed high refractive index glasses that were used for precision molding to fabricate periodic SWSs. One-dimensional periodic SWSs were fabricated on the glass surface by a precision molding method using a SiC mold on which the reverse of the SWS pattern was carved and a flat SiC mold. One-dimensional SWSs with a high aspect ratio were fabricated on one surface of the glass plate. The niobium phosphate glass plates with the one-dimensional SWS showed phase retardation higher than 1/8l between TE- and TM-polarized beams at 400 nm, demonstrating that a wavelength plate can be fabricated by our precision molding technique.

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Kim, Il Ho, Jung Il Lee, G. S. Choi, and J. S. Kim. "Physical Property Evaluation for High Purity Niobium and Tantalum Rare Metals." Advanced Materials Research 26-28 (October 2007): 1059–62. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.1059.

Повний текст джерела

Анотація:

Thermal, electrical and mechanical properties of high purity niobium and tantalum refractory rare metals were investigated to evaluate the physical purity. Higher purity niobium and tantalum metals showed lower hardness due to smaller solution hardening effect. Temperature dependence of electrical resistivity showed a typical metallic behavior. Remarkable decrease in electrical resistivity was observed for a high purity specimen at low temperature. However, thermal conductivity increased for a high purity specimen, and abrupt increase in thermal conductivity was observed at very low temperature, indicating typical temperature dependence of thermal conductivity for high purity metals. It can be known that reduction of electron-phonon scattering leads to increase in thermal conductivity of high purity niobium and tantalum metals at low temperature.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Bliznyuk, Antonina, and Valentin Kozin. "NIOBIUM’S BEHAVIOR IN AQUEOUS HYDROFLUORIC ACID SOLUTION." Ukrainian Chemistry Journal 87, no. 8 (September 24, 2021): 116–26. http://dx.doi.org/10.33609/2708-129x.87.08.2021.116-126.

Повний текст джерела

Анотація:

Thanks to the unique combination of physicochemical properties, niobium and its compounds are widely used in various fields of science and technology. The main areas of niobium’s applications are the production of superconductors, nuclear energy, chemical engineering, metallurgy, manufacture of optically active materials, thin-film lithium batteries, fuel cells. The aim of this work is to study the processes that take place on the niobium electrode in aqueous solutions of hydrofluoric acid, as well as to establish the composition of niobium compounds that are formed. The paper presents the results of studies the behavior of the niobium electrode in aqueous solutions 0.25 N. hydrofluoric acid. The kinetic parameters of the processes occurring at the phase boundary are determined. It was found that the anodic polarization of the niobium electrode is accompanied by the formation of a passive layer, the destruction of which is facilitated by increasing the polarization potential and fluorine anions, in the presence of which complex fluoroiobate anions [NbF7]2- and [NbOF5]2-are formed. Cathodic polarization of niobium is accompanied by the formation of hydrides on its surface, which causes an increase in the overvoltage of hydrogen evolution. The anodic polarization of the niobium electrode in a solution of hydrofluoric acid causes the formation on its surface of a passive layer, which is destroyed with increasing potential. In the Nbo–NbO2–0.25 –0.25 n HF system, [NbF7]2-anions are formed, as evidenced by bands in the region of 500 nm on the electron absorption spectra. The rate constants of [NbF7]2- and [NbOF5]2- formation are estimated at 3.78 • 10-3 s-1 and 5.18 • 10-3 s-1, respectively. The reduction of hydrogen at the niobium cathode from a solution of hydrofluoric acid is accompanied by the formation of hydrides, which causes an increase in the overvoltage of hydrogen evolution and high values of the angular coefficients of the Tafel dependence.

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Koethe, Alfred, and Jens Ingolf Moench. "Preparation of Ultra High Purity Niobium." Materials Transactions, JIM 41, no. 1 (2000): 7–16. http://dx.doi.org/10.2320/matertrans1989.41.7.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Ju, L., M. Baker, and D. G. Blair. "High-Q niobium membrane flexure pendulum." Physics Letters A 280, no. 4 (February 2001): 182–84. http://dx.doi.org/10.1016/s0375-9601(01)00045-7.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Kumar, P. "High purity niobium for superconducting applications." Journal of the Less Common Metals 139, no. 1 (April 1988): 149–58. http://dx.doi.org/10.1016/0022-5088(88)90337-2.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Hribernik, B., G. Hackl, S. Karagoz, and H. Fischmeister. "Niobium in PM high speed steels." Metal Powder Report 46, no. 5 (May 1991): 58–62. http://dx.doi.org/10.1016/0026-0657(91)91760-4.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

17

Ranade, A. J., and S. V. Salvi. "Some niobium containing high temperature relaxors." Ferroelectrics 197, no. 1 (June 1997): 179–84. http://dx.doi.org/10.1080/00150199708008408.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Kučerová, L., K. Opatová, J. Káňa, and H. Jirková. "High Versatility of Niobium Alloyed AHSS." Archives of Metallurgy and Materials 62, no. 3 (September 26, 2017): 1485–91. http://dx.doi.org/10.1515/amm-2017-0230.

Повний текст джерела

Анотація:

AbstractThe effect of processing parameters on the final microstructure and properties of advanced high strength CMnSiNb steel was investigated. Several processing strategies with various numbers of deformation steps and various cooling schedules were carried out, namely heat treatment without deformation, conventional quenching and TRIP steel processing with bainitic hold or continuous cooling. Obtained multiphase microstructures consisted of the mixture of ferrite, bainite, retained austenite and M-A constituent. They possessed ultimate tensile strength in the range of 780-970 MPa with high ductility A5mmabove 30%. Volume fraction of retained austenite was for all the samples around 13%. The only exception was reference quenched sample with the highest strength 1186 MPa, lowest ductility A5mm= 20% and only 4% of retained austenite.

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Kochanov, G. P., A. N. Rogova, I. A. Kovalev, S. V. Shevtsov, A. I. Sitnikov, A. V. Kostyuchenko, S. N. Klimaev, et al. "Preparation of Niobium Carbide-Based High-Temperature Ceramics by Direct Niobium Carburization." Inorganic Materials 57, no. 10 (October 2021): 1077–82. http://dx.doi.org/10.1134/s0020168521100058.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Subramanian, Sundaresa V., M. Kashif Rehman, Hatem S. Zurob, and Cheng Jia Shang. "Recrystallization and Grain Coarsening Control in Processing High Niobium Microalloyed Line Pipe Steels." Materials Science Forum 753 (March 2013): 391–96. http://dx.doi.org/10.4028/www.scientific.net/msf.753.391.

Повний текст джерела

Анотація:

The effect of solute niobium in retarding coarsening kinetics of austenite in upstream thermo mechanical processing of high niobium (0.1wt%Nb) low interstitial steel is analyzed. Solute drag effect of niobium in retarding boundary mobility in static recrystallization is examined in thermo-mechanical rolling of high Nb microalloyed steel. The importance of austenite grain refinement prior to pancaking in compact strip rolling of high Nb microallyed steel as a means to increase surface area to volume ratio of pancaked austenite grain is emphasized. This is to promote adequate nucleation sites for phase transformation even under conditions low total rolling reduction below temperature of no recrystallization.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

Huang, Sheng, Changrong Li, Zhiying Li, Zeyun Zeng, Yongqiang Zhai, Jie Wang, Zhanlin Liu, and Changling Zhuang. "Quantitative analysis of microstructure and mechanical properties of Nb–V microalloyed high-strength seismic reinforcement with different Nb additions." High Temperature Materials and Processes 40, no. 1 (January 1, 2021): 300–309. http://dx.doi.org/10.1515/htmp-2021-0031.

Повний текст джерела

Анотація:

Abstract HRB500E seismic steel bars are mainly used in high-rise buildings near the seismic zone. The influence of different niobium contents (0–0.023%) on the microstructure and mechanical properties of HRB500E seismic reinforcement was studied. Results showed that the grain size of ferrite was between 3.6 and 8.3 μm when only V was added. Meanwhile, as the niobium content increases, the ferrite particles are further refined. After adding niobium, the grain contribution increased by 9%. The addition of niobium significantly refined the grain size of HRB500E seismic reinforcement. The second-phase nano-elliptic precipitate is NbC. The precipitated phase is dispersed on the grain boundary and the matrix, and the dislocation density on the matrix promotes the precipitation of NbC particles along the dislocation line. The second-phase precipitation of niobium can form an effective pinning effect and then refine the pearlite spacing. The microhardness and the tensile strength also significantly improved. The yield strength increased from 509 to 570 MPa.

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Wentzcovitch, Alexandre, Francisco Ambrozio Filho, Luís Carlos Elias da Silva, and Maurício David Martins das Neves. "Sintering of AISI M₂ High Speed Steel with the Addition of NbC." Materials Science Forum 727-728 (August 2012): 90–95. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.90.

Повний текст джерела

Анотація:

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 M2steel. Optical and scanning electron microscope observations revealed a microstructure with uniformly distributed niobium carbides.

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Mohrbacher, Hardy, and Christian Klinkenberg. "The Role of Niobium in Lightweight Vehicle Construction." Materials Science Forum 537-538 (February 2007): 679–86. http://dx.doi.org/10.4028/www.scientific.net/msf.537-538.679.

Повний текст джерела

Анотація:

Modern vehicle bodies make intensive use of high strength steel grades to improve the weight and the mechanical performance simultaneously. A broad range of medium and extra high strength steel grades is available. These steel grades have different characteristics concerning strength, formability and weldability. For many steel grades microalloying by niobium is the key to achieve their characteristic property profile. In HSLA steels niobium enhances the strength primarily by grain refinement. In interstitial free high strength steels niobium serves as a stabilizing element and also assists in obtaining the bake hardening effect. Some modern multiphase steels rely on niobium to achieve additional strength via grain refinement and precipitation hardening. Microstructural control provides a way to further optimize properties relevant to automotive processing such as cutting, forming and welding. The relevance of niobium microalloying in that respect will be outlined.

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Sankar, M., K. V. Mirji, V. V. Satya Prasad, R. G. Baligidad, and A. A. Gokhale. "Purification of Niobium by Electron Beam Melting." High Temperature Materials and Processes 35, no. 6 (June 1, 2016): 621–27. http://dx.doi.org/10.1515/htmp-2014-0218.

Повний текст джерела

Анотація:

AbstractPure niobium metal, produced by alumino-thermic reduction of niobium oxide, contains various impurities which need to be reduced to acceptable levels to obtain aerospace grade purity. In the present work, an attempt has been made to refine niobium metals by electron beam drip melting technique to achieve purity confirming to the ASTM standard. Input power to the electron gun and melt rate were varied to observe their combined effect on extend of refining and loss of niobium. Electron beam (EB) melting is shown to reduce alkali metals, trace elements and interstitial impurities well below the specified limits. The reduction in the impurities during EB melting is attributed to evaporation and degassing due to the combined effect of high vacuum and high melt surface temperature. The % removal of interstitial impurities is essentially a function of melt rate and input power. As the melt rate decreases or input power increases, the impurity levels in the solidified niobium ingot decrease. The EB refining process is also accompanied by considerable amount of niobium loss, which is attributed to evaporation of pure niobium and niobium sub-oxide. Like other impurities, Nb loss increases with decreasing melt rate or increase in input power.

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Baranets, Sviatoslav, Hua He, and Svilen Bobev. "Niobium-bearing arsenides and germanides from elemental mixtures not involving niobium: a new twist to an old problem in solid-state synthesis." Acta Crystallographica Section C Structural Chemistry 74, no. 5 (April 20, 2018): 623–27. http://dx.doi.org/10.1107/s2053229618005739.

Повний текст джерела

Анотація:

Three isostructural transition-metal arsenides and germanides, namely niobium nickel arsenide, Nb0.92(1)NiAs, niobium cobalt arsenide, NbCoAs, and niobium nickel germanide, NbNiGe, were obtained as inadvertent side products of high-temperature reactions in sealed niobium containers. In addition to reporting for the very first time the structures of the title compounds, refined from single-crystal X-ray diffraction data, this article also serves as a reminder that niobium containers may not be suitable for the synthesis of ternary arsenides and germanides by traditional high-temperature reactions. Synthetic work involving alkali or alkaline-earth metals, transition or early post-transition metals, and elements from groups 14 or 15 under such conditions may yield Nb-containing products, which at times could be the major products of such reactions.

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Wang, Liu, Xiaofang Bi, and Shubin Yang. "Synergic antimony–niobium pentoxide nanomeshes for high-rate sodium storage." Journal of Materials Chemistry A 6, no. 15 (2018): 6225–32. http://dx.doi.org/10.1039/c8ta01130c.

Повний текст джерела

Анотація:

Synergic antimony–niobium pentoxide nanomeshes are fabricated on a large scaleviathe controllable decomposition of SbNbO₄nanosheets, which are obtained from ultrathin hydrated niobium oxide (Nb₂O₅·nH₂O) layers. Synergizing the merits of highly active Sb and structurally stable Nb₂O₅, the nanomeshes exhibit enhanced charge-transfer kinetics, thus leading to a high capacity and good high-rate performance for sodium storage.

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Smid, Ivi, and Gaurav Aggarwal. "Powder Injection Molding of Niobium." Materials Science Forum 475-479 (January 2005): 711–16. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.711.

Повний текст джерела

Анотація:

Niobium and niobium-based alloys are used in a variety of high temperature applications ranging from light bulbs to rocket engines. Niobium has excellent formability and the lowest specific weight among refractory metals (Nb, Ta, Mo, W, and Re). Powder injection molding of niobium powder was investigated for efficiency of the process. The sintering of injection molded bars was conducted up to 2000°C in vacuum and low oxygen partial pressure atmosphere. This paper investigates the effect of sintering time, temperature and atmosphere on processing of pure niobium.

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Golosienko, S. A., N. A. Minyakin, V. V. Ryabov, T. G. Semicheva, and E. I. Khlusova. "The effect of microalloying on mechanical properties of low-carbon chromium-nickel-molybdenum steel." Voprosy Materialovedeniya, no. 1(97) (August 10, 2019): 7–14. http://dx.doi.org/10.22349/1994-6716-2019-97-1-07-14.

Повний текст джерела

Анотація:

The work covers the effect of niobium, as well as niobium and vanadium together, on mechanical properties of high-strength chromium-nickel-molybdenum steel after thermal improvement (heat treatment). The mechanical properties of steels are determined after applying various tempering temperatures (from 580 to 660°C), durations of tempering (from 1 to 16 hours), and also after quenching from rolling heat and furnace heat with subsequent tempering. It is shown that after quenching and tempering in the temperature range 580– 660°C, simultaneous microalloying by niobium and vanadium, compared to microalloying by niobium alone, increases the yield strength but in significantly decreases toughness and ductility. Quenching from rolling heat increases strength while maintaining high toughness and the increase in strength is most noticeable for steel microalloyed only by niobium.

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Przybylski, K., J. Prazuch, T. Brylewski, and E. Durda. "High Temperature Oxidation Behaviour of Tial8Nb Alloy." Archives of Metallurgy and Materials 58, no. 2 (June 1, 2013): 477–80. http://dx.doi.org/10.2478/amm-2013-0021.

Повний текст джерела

Анотація:

The goal of this work is to determine the effect of niobium on the kinetics and mechanism of Ti-Al oxidation in air. In order to compare the oxidation kinetics of Ti-Al and Ti-Al with the addition of niobium, isothermal oxidation was performed on Ti-48Al and Ti-46Al-8Nb (in at.%) alloys at 1073 K in synthetic air. Cyclic oxidation of Ti-46Al and Ti-46Al-8Nb alloys was carried out in laboratory air for 42 cycles (1 cycle, 24 hrs). The morphology, as well as chemical and phase composition of the oxidation products were investigated using X-ray Diffraction (XRD) and Scanning Electron Microscopy combined with Energy Dispersive Spectroscopy (SEM-EDS). From these investigations it can be concluded that niobium addition increases the corrosion resistance of TiAl and, furthermore, improves the adherence between the metallic substrate and the oxide scale. The oxidation mechanism of Ti-46Al-8Nb was studied via secondary neutral mass spectroscopy (SNMS) after two-stage isothermal oxidation (24 hrs in 16O2 followed by 24 hrs in 18O2) at 1073 K. From this analysis it can be assumed that the oxidation mechanism of Ti-46Al-8Nb alloy consists of simultaneous outward titanium and aluminum diffusion and inward oxygen transport.

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Knittel, S., S. Mathieu, and M. Vilasi. "Nb4Fe4Si7 coatings to protect niobium and niobium silicide composites against high temperature oxidation." Surface and Coatings Technology 235 (November 2013): 144–54. http://dx.doi.org/10.1016/j.surfcoat.2013.07.027.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Divinski, Sergiy, Frank Hisker, Christian Klinkenberg, and Christian Herzig. "Niobium and titanium diffusion in the high niobium-containing Ti–54Al–10Nb alloy." Intermetallics 14, no. 7 (July 2006): 792–99. http://dx.doi.org/10.1016/j.intermet.2005.12.007.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Li, Shenghao, Xiaohuan Wang, Zhiming Shi, Jun Wang, Guojun Ji, and Xinba Yaer. "High-Performance Lithium-Ion Storage of FeTiO3 with Morphology Adjustment and Niobium Doping." Materials 15, no. 19 (October 6, 2022): 6929. http://dx.doi.org/10.3390/ma15196929.

Повний текст джерела

Анотація:

Ferrous titanate (FeTiO3) has a high theoretical capacity and physical and chemical properties stability, so it is a potential lithium anode material. In this study, FeTiO3 nanopowder and nanosheets were prepared by the sol–gel method and the hydrothermal method. In addition, niobium-ion doping was carried out, the radius of Nb close to Ti so the Nb can easily enter into the FeTiO3 lattice. Nb can provide more free electrons to improve the electrochemical performance. Then, the effects of the morphology and niobium doping on the microstructure and electrochemical properties of FeTiO3 were systematically studied. The results show that FeTiO3 nanosheets have a better lithium storage performance than nanopowders because of its high specific surface area. A certain amount of niobium doping can improve the electrochemical performance of FeTiO3. Finally, a 1 mol% niobium-doping FeTiO3 nanosheets (1Nb-FTO-S) electrode provided a higher specific capacity of 782.1 mAh g−1 at 50 mA g−1. After 200 cycles, the specific capacity of the 1Nb-FTO-S electrode remained at 509.6 mAh g−1. It is revealed that an increased specific surface area and ion doping are effective means to change the performance of lithium, and the proposed method looks promising for the design of other inorganic oxide electrode materials.

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Zou, De Hui, Zhi Fang Peng, Ping He Li, and Ai Min Guo. "Effect of Niobium on the Microstructure and Mechanical Properties of Low Carbon Steel Plate with Intercritical Quenching." Advanced Materials Research 152-153 (October 2010): 1382–86. http://dx.doi.org/10.4028/www.scientific.net/amr.152-153.1382.

Повний текст джерела

Анотація:

The microstructure and mechanical properties of the low carbon steel plates containing Niobium content of 0.038%, 0.063% and 0.082% with intercritical quenching were studied by SEM, TEM, tensile and impact tests. The results showed that the intercritical quenching steel with high Niobium content can gain the fine microstructure , but also easily obtain the martensite, which made the strength very high but low temperature toughness very low, however, the steel with low Niobium content can not reach enough austenitization level, which caused both low temperature and yield ratio high relatively. So in the given rolling and heat treatment process, there was suitable Niobium content can contribute to obtain the optimal austenization level resulting in the good combination of strength, yield ratio, elongation and low temperature toughness after intercritical quenching in the low carbon steel.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Zillgen, H., M. Stenzel, and W. Lohwasser. "New Niobium Capacitors with Stable Electrical Parameters." Active and Passive Electronic Components 25, no. 2 (2002): 147–53. http://dx.doi.org/10.1080/08827510212339.

Повний текст джерела

Анотація:

The replacement of the anode material in tantalum capacitors by a new generation of high CV niobium powders offers the possibility to get an economical alternative to tantalum for a wide range of applications. Due to the high CV potential of niobium powder there is also an alternative to low voltage aluminum electrolytic capacitors. We developed a new niobium capacitor which shows stable electrical values. By optimizing the structure of the dielectric and the cathodic layers as well as the process parameters we gained a capacitor which can be used up to105 °C. Electrical characteristics and lifetest behavior of niobium capacitors out of 100 k–150 k CV/g powder will be discussed.

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Wang, Hong Po, Bo Peng, Li Feng Sun, Cheng Jun Liu, and Mao Fa Jiang. "Microstructure and Precipitates of High-Pure Ferritic Stainless Steels Stabilized by Niobium and Titanium." Materials Science Forum 749 (March 2013): 7–12. http://dx.doi.org/10.4028/www.scientific.net/msf.749.7.

Повний текст джерела

Анотація:

As stabilization elements added into ferritic stainless steels, various kinds of precipitates of niobium and titanium will form and have great effect on their microstructure, which has great effect on the mechanical and corrosion properties of the final products. Combined with thermodynamic calculation by FactSage software, microstructure and precipitates of ferritic stainless steels containing different niobium and titanium were investigated by optical microscope, scanning electron microscope, transmission electron microscope and energy dispersive spectrometer. The results show that titanium mainly exists in form of TiN but niobium exists mainly in form of NbC. Moreover, a certain amount of NbN particles precipitate when there is not enough titanium to react with nitrogen. TiN particles with size of 2μm~8μm promote the recrystallization but Nb-rich precipitates with size of less than 500nm suppress the recrystallization in the process of annealing.

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Sheng-Feng, Liu, Lin Jian-Hua, and Su Mian-Zeng. "Thermodynamics of Deoxidation of High Purity Niobium." Acta Physico-Chimica Sinica 15, no. 03 (1999): 228–33. http://dx.doi.org/10.3866/pku.whxb19990307.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

37

Moench, Jens Ingolf, Ingrid Stephan, and Alfred Koethe. "High Purity Niobium for Neutron Activation Detectors." Materials Transactions, JIM 41, no. 1 (2000): 67–70. http://dx.doi.org/10.2320/matertrans1989.41.67.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

38

Yin, L., L. Yang, and D. Yi. "High temperature oxidation resistance coating on niobium." Materials Science and Technology 21, no. 5 (May 2005): 579–82. http://dx.doi.org/10.1179/174328405x43009.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

39

BOUILLET, C. "Oxidation of niobium sheets at high temperature." Solid State Ionics 101-103 (November 1997): 819–24. http://dx.doi.org/10.1016/s0167-2738(97)00297-x.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

40

Singer, X. "High purity niobium for Tesla Test Facility." Matériaux & Techniques 91, no. 7-8-9 (2003): 28–32. http://dx.doi.org/10.1051/mattech/200391070028.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Mirvakili, Seyed M., Mehr Negar Mirvakili, Peter Englezos, John D. W. Madden, and Ian W. Hunter. "High-Performance Supercapacitors from Niobium Nanowire Yarns." ACS Applied Materials & Interfaces 7, no. 25 (June 19, 2015): 13882–88. http://dx.doi.org/10.1021/acsami.5b02327.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Padamsee, H. "High purity niobium for superconducting accelerator cavities." Journal of the Less Common Metals 139, no. 1 (April 1988): 167–78. http://dx.doi.org/10.1016/0022-5088(88)90339-6.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Stephens, J. J. "Recent advances in high-temperature niobium alloys." JOM 42, no. 8 (August 1990): 22–23. http://dx.doi.org/10.1007/bf03221047.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

44

Li Chengren and D. Larbalestier. "Very high current density niobium Titanium composites." IEEE Transactions on Magnetics 23, no. 2 (March 1987): 1646–49. http://dx.doi.org/10.1109/tmag.1987.1064991.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

45

Barth, E. P., J. K. Tien, S. Uejo, and S. Kambara. "High temperature strength of niobium aluminide intermetallics." Materials Science and Engineering: A 153, no. 1-2 (May 1992): 398–401. http://dx.doi.org/10.1016/0921-5093(92)90227-r.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

46

Guo, Jing, Gongchang Lin, Shu Cai, Chuanying Xi, Changjin Zhang, Wanshuo Sun, Qiuliang Wang, et al. "Record‐High Superconductivity in Niobium–Titanium Alloy." Advanced Materials 31, no. 11 (January 7, 2019): 1807240. http://dx.doi.org/10.1002/adma.201807240.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

47

Maheshwari, P., F. A. Stevie, G. R. Myneni, G. Ciovati, J. M. Rigsbee, P. Dhakal, and D. P. Griffis. "SIMS analysis of high-performance accelerator niobium." Surface and Interface Analysis 46, S1 (March 21, 2014): 288–90. http://dx.doi.org/10.1002/sia.5461.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Mohrbacher, Hardy, Jer-Ren Yang, Yu-Wen Chen, Johannes Rehrl, and Thomas Hebesberger. "Metallurgical Effects of Niobium in Dual Phase Steel." Metals 10, no. 4 (April 12, 2020): 504. http://dx.doi.org/10.3390/met10040504.

Повний текст джерела

Анотація:

Dual phase (DP) steels are widely applied in today’s automotive body design. The favorable combination of strength and ductility in such steels is in first place related to the share of ferrite and martensite. The pronounced work hardening behavior prevents localized thinning and allows excellent stretch forming. Niobium microalloying was originally introduced to dual phase steel for improving bendability by refining the microstructure. More recently developed “high ductility” (HD) DP steel variants provide increased drawability aided by a small share of austenite retained in the microstructure. In this variant niobium microalloying produces grain refinement and produces a dispersion of nanometer-sized carbide precipitates in the steel matrix which additionally contributes to strength. This study investigates the microstructural evolution and progress of niobium precipitation during industrial processing of high-ductility DP 980. The observations are interpreted considering the solubility and precipitation kinetics of niobium. The influences of niobium on microstructural characteristics and its contributions to strength and formability are discussed.

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Ye, Xiao Yu, Kai Hua Zhang, and Jun Zuo. "The Effects of Rolling Process on Microstructures of High Nb X70 Grade Pipeline Steel." Advanced Materials Research 396-398 (November 2011): 177–81. http://dx.doi.org/10.4028/www.scientific.net/amr.396-398.177.

Повний текст джерела

Анотація:

In Gleele-3500 thermal simulation test machine, conduct thermal simulation experiment for high niobium X70 grade pipeline steel at different heating temperature, deformation temperature, deformation extent, cooling rate and coiling temperature. Analysis that the microstructure was influenced by different heating temperature and rolling process. The results showed that, For high niobium X70 grade pipeline steel, controlled heating temperature was1200±20°C, using HTP process, in large cooling rate range all can get the uniform acicular ferrite microstructures.

Стилі APA, Harvard, Vancouver, ISO та ін.

50

He, Cheng, and Gregory C. Stangle. "The mechanism and kinetics of the niobium-carbon reaction under self-propagating high-temperature synthesis-like conditions." Journal of Materials Research 10, no. 11 (November 1995): 2829–41. http://dx.doi.org/10.1557/jmr.1995.2829.

Повний текст джерела

Анотація:

The mechanism and kinetics of the chemical reaction between Nb(s) and C(s) under self-propagating high-temperature synthesis (SHS)-like (or combustion synthesis-like) conditions have been studied. Experiments were designed and conducted in order to produce a transport-resistance-free reaction between Nb and C under time-temperature conditions that are characteristic of the combustion synthesis process. To do so, a reaction couple, consisting of carbon and either a thin niobium foil or a fine niobium wire, was used. The effects of the temperature history and the formation of a liquid phase on the reaction were studied. In addition, theoretical experiments of the reaction were also conducted. The results showed that at high temperatures, layered niobium carbide phases formed in a direction that was parallel to the original carbon-niobium interface. As might be expected, local melting played a very significant role in the reactions. The mechanism and kinetics of these reactions provide a fundamental understanding of the manner and rate by which a powder-based Nb/C SHS process takes place, and, by extension, to a large, general class of solid-solid material synthesis processes that are based on the SHS (or combustion synthesis) process.

Стилі APA, Harvard, Vancouver, ISO та ін.

Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!