Thematische Bibliographien / Transparent polycrystalline ceramics

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Auswahl der wissenschaftlichen Literatur zum Thema „Transparent polycrystalline ceramics“

Autor: Grafiati

Veröffentlicht am 28. Juni 2021

Zuletzt aktualisiert am 5. Februar 2022

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Zeitschriftenartikel zum Thema "Transparent polycrystalline ceramics"

Weinan Gao, Weinan Gao, Yu Shen Yu Shen, Yong Bo Yong Bo, Wenping Zhang Wenping Zhang, Yong Bi Yong Bi und and Zuyan Xu and Zuyan Xu. „Optical and ESR study of Nd:YAG transparent polycrystalline ceramics“. Chinese Optics Letters 15, Nr. 5 (2017): 051601–51603. http://dx.doi.org/10.3788/col201715.051601.

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Ayman, Muhammad Tsabit, Hyeon Mo Bae, Heejin Kwon, Jaehyung Lee und Dang-Hyok Yoon. „Transparent Polycrystalline γ-AlON Ceramics“. Ceramist 23, Nr. 3 (30.09.2020): 244–60. http://dx.doi.org/10.31613/ceramist.2020.23.3.01.

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Johnson, Roy, P. Biswas, P. Ramavath, R. S. Kumar und G. Padmanabham. „Transparent Polycrystalline Ceramics: An Overview“. Transactions of the Indian Ceramic Society 71, Nr. 2 (Juni 2012): 73–85. http://dx.doi.org/10.1080/0371750x.2012.716230.

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Yang, Hao, Jian Zhang, Dewei Luo, Hui Lin, Deyuan Shen und Dingyuan Tang. „Novel transparent ceramics for solid-state lasers“. High Power Laser Science and Engineering 1, Nr. 3-4 (20.12.2013): 138–47. http://dx.doi.org/10.1017/hpl.2013.18.

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AbstractRecent progress on rare-earth doped polycrystalline YAG transparent ceramics has made them an alternative novel solid-state laser gain material. In this paper we present results of our research on polycrystalline RE:YAG transparent ceramics. High optical quality YAG ceramics doped with various rare-earth (RE) ions such as ${\rm Nd}^{3+}$, ${\rm Yb}^{3+}$, ${\rm Er}^{3+}$, ${\rm Tm}^{3+}$, and ${\rm Ho}^{3+}$ have been successfully fabricated using the solid-state reactive sintering method. Highly efficient laser oscillations of the fabricated ceramics are demonstrated.

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Li, Qing, Guo Ping Zhang, Yang Liu, Hao Wang und Li Wen Lei. „Effect of Microstructure on Transmission Properties of Polycrystalline Transparent Ceramics“. Materials Science Forum 704-705 (Dezember 2011): 842–46. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.842.

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The transmission properties of polycrystalline transparent ceramics are influenced by the chemical composition and the microstructure of the material. The fundamental optical mechanism of transparent ceramics and the influencing factors on transmission properties were discussed in this paper. The Mie theory for light scattering is applied to calculate scattering coefficients of residual pores and optical birefringence. The in-line transmission curves of the transparent alumina were calculated as a function of pore size, porosity and grain size. The results show that scattering by the residual pores is the dominant influencing factors on transmission properties. The scattering by the residual pores increases with an increase in porosity and the maximum of the scattering was observed when the pore size close to the optical wavelength. Optical birefringence in the transparent ceramics with non-cubic crystal structure has an important effect on the in-line transmission. The in-line transmission increases with a decrease in grain size. Keywords: transparent ceramics; microstructure; light scattering; birefringence

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Joshi, Bhupendra, Hyun Hwi Lee, Seung Ho Kim, Zheng Yi Fu, Koichi Niihara und Soo Wohn Lee. „Boron Nitride Doped Transparent Polycrystalline Silicon Nitride Ceramics“. Materials Science Forum 658 (Juli 2010): 428–31. http://dx.doi.org/10.4028/www.scientific.net/msf.658.428.

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The addition of h- BN to a polycrystalline Si3N4 was to increase the fracture toughness and other mechanical properties such as flexural strength and hardness of the material. The hot pressed samples were prepared from the mixture of α-Si3N4, AlN, MgO and h-BN. The composite contained from 0 to 2 wt.% BN powder with sintering aids (9% AlN + 3% MgO). The transparency, mechanical properties and microstructure of hot pressed polycrystalline Si3N4-BN composite materials were investigated by UV/VIS spectrophotometer, scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The transparency decreased with increasing the content of h-BN into Si3N4.

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Mao, Xiaojian, Shiwei Wang, Shunzo Shimai und Jingkun Guo. „Transparent Polycrystalline Alumina Ceramics with Orientated Optical Axes“. Journal of the American Ceramic Society 91, Nr. 10 (Oktober 2008): 3431–33. http://dx.doi.org/10.1111/j.1551-2916.2008.02611.x.

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Joshi, Bhupendra, Gobinda Gyawali und Soo Lee. „Recent advances in transparent / translucent polycrystalline Sialon ceramics“. Letters on Materials 10, Nr. 2 (2020): 158–63. http://dx.doi.org/10.22226/2410-3535-2020-2-158-163.

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Zeng Zhi-Jiang, Yang Qiu-Hong und Xu Jun. „Spectroscopic characteristics of Cr3+:Al2O3 polycrystalline transparent alumina ceramics“. Acta Physica Sinica 54, Nr. 11 (2005): 5445. http://dx.doi.org/10.7498/aps.54.5445.

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YAGI, Hideki, und Takagimi YANAGITANI. „Recent Progress in Transparent Polycrystalline Ceramics for Optical Applications“. Review of Laser Engineering 39, Nr. 5 (2011): 300–305. http://dx.doi.org/10.2184/lsj.39.300.

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Dissertationen zum Thema "Transparent polycrystalline ceramics"

Mouzon, Johanne. „Synthesis of Yb:Y2O3 nanoparticles and fabrication of transparent polycrystalline yttria ceramics“. Licentiate thesis, Luleå, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17509.

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More efficient laser materials are needed for space applications in order to save weight and make cost-savings. The fabrication of polycrystalline ceramic materials is a solution to obtain new compositions with better efficiency. In order to produce a Yb doped Y2O3 laser material, we developed a process to obtain yttrium oxide nanosized particles doped with ytterbium and a sintering method that leads to transparent polycrystalline ceramics. First, nano-powder of yttria was fabricated from a precursor with transient morphology, i.d. yttrium hydroxynitrate platelets that decompose into spherical yttria nano-particles during calcination. The influence of different dewatering methods on such precursors was investigated. Water removal by freeze-drying was shown to be optimal for the production of non- agglomerated nano-particles compared with other methods that involve solvent removal by evaporation. This was attributed to the ability of freeze-drying to avoid the formation of solid bridges, since water is directly removed by sublimation. In a second step, doping with ytterbium was performed. Two precipitation routes were compared: precipitation of hydroxynitrate platelets and precipitation of amorphous carbonate. This latter was shown to allow a better distribution of ytterbium in the yttrium oxide matrix after calcination of the corresponding precursor. This was explained in terms of the good cation mixing in the amorphous particles, while formation of the hydroxynitrate platelets resulted in segregation of ytterbium, probably because a second phase with different ytterbium/yttrium composition precipitates in the first stages of the synthesis. Finally, a method combining pre-sintering in vacuum followed by hot isostatic pressing was shown to be successful to produce transparent yttria ceramics from agglomerated powders with high purity. Pre-sintering in vacuum agglomerates of closely-packed particles enables differential sintering, which is responsible for the complete elimination of porosity in the agglomerates and for the formation of intergranular porosity only. Then, hot isostatic pressing treatment of the pre-sintered samples using the glass-canning technique reactivates sintering and coarsening, which causes almost complete pore elimination. Furthermore, a liquid phase formed during sintering because of pollution from the furnace. This liquid phase is thought of as to have helped densification to some extent. The best transparent ceramic showed a transmittance of 43% at 400 nm.
Godkänd; 2005; 20061221 (haneit)

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Mouzon, Johanne. „Synthesis of Yb:Y₂O₃ nanoparticles and fabrication of transparent polycrystalline yttria ceramics /“. Luleå, 2005. http://epubl.luth.se/1402-1757/2005/29.

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Chvíla, Martin. „Příprava transparentní pokročilé keramiky na bázi Al2O3.MgO“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442599.

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Ceramic materials are in general characterized by high hardness, high modulus of elasticity, excellent abrasion resistance, etc. These properties make ceramics among others useful in optically transparent applications. An ideal form of optically transparent ceramic material is monocrystalline. However, the monocrystalline fabrication is expensive and/or time consuming. From this point of view polycrystalline ceramics is preferred. But the polycrystalline transparent ceramics fabrication is fraught with complications such as porosity, inappropriate grain size and insufficient purity. These circumstances could be solved by using sintering additives. This master’s thesis compiles literature research summarizing modern technologies of advanced ceramics sintering and ceramic polycrystalline microstructure dependence on its optical properties. The experimental part of this thesis focuses on the fabrication parameters of polycrystalline advanced ceramics based on Al2O3MgO and evaluation of their optical properties. Polycrystalline magnesium-aluminate spinel with sintering additive contents 0; 0.3 and 0.6 weight % LiOH was fabricated by optimalisation of Spark Plasma Sintering cycle. Fully dense ceramic samples of polycrystalline magnesium-aluminate spinel with favourable optical properties in visible spectrum radiation were achieved. Real In-line Transmission RIT and Total Forward Transmittance TFT were analysed. RIT exceeded 84 % at wavelength of 633 nm and TFT exceeded 83 % at wavelength above 860 nm. The decisive factors in terms of the optical properties of ceramics sintered with sintering additives were the amount of time-spending at high temperatures and the purity of ceramic powders.

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Katz, Aurélien. „Élaboration de céramiques polycristallines transparentes Er ³+ : YAG par Spark Plasma Sintering pour applications laser de puissance“. Thesis, Valenciennes, 2016. http://www.theses.fr/2016VALE0007.

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Cette étude s’intéresse à l’amélioration des performances du laser solide Er3+:YAG, dont la longueur d’onde de 1,64 µm est dite « eye-safe ». L’une des solutions est le remplacement des monocristaux actuellement utilisés comme milieu amplificateur par des céramiques polycristallines Er:YAG transparentes, dont les propriétés thermomécaniques remarquables permettent une meilleure cohérence du faisceau de sortie et de ce fait, une augmentation des performances du laser. Cependant, la réunion des différents critères requis pour obtenir la transparence reste un réel challenge dans l’élaboration de ces céramiques. L’utilisation de poudres commerciales issues de deux voies de synthèse différentes a permis de souligner le rôle primordial des caractéristiques physiques de la poudre sur le comportement à la compaction et au frittage, effectué par Spark Plasma Sintering, tandis que la composition phasique et la pureté chimique conditionnent la qualité optique finale. Il ressort également que la coloration de la céramique observée lors du frittage résulte, non pas d’une contamination au carbone, mais de la formation de lacunes d’oxygène. Enfin, l’analyse et la compréhension du mode d’action du LiF utilisé comme aide au frittage ont permis d’établir des mécanismes réactionnels permettant d’optimiser le cycle de frittage. Cette démarche a conduit à l’obtention de céramiques polycristallines transparentes (Ø = 30 mm, e = 3 mm) à qualité optique élevée avec des valeurs de transmission de 80 % à 400 nm et 84 % à 1100 nm. Sur la base de ces résultats et de la simulation numérique, un changement d’échelle des céramiques (Ø = 50 mm, e = 5 mm) a été effectué dans le but de les évaluer en cavité laser
This work focus on the improvement of the solid state Er3+:YAG laser performances presenting an "eye-safe" wavelength at 1.64 µm. One way is the replacement of single crystals currently used as gain media by polycrystalline ceramics as they present improved thermo-mechanical properties allowing a longer use of the laser. However, the meeting of different criteria requested to get transparency remains a challenge in the development of these ceramics. The use of commercial powders produced by two different synthesis ways allowed to highlight the essential role of the physico-chemical characteristics of the powder on compaction and sintering behaviors, performed by Spark Plasma Sintering, Phase composition and chemical purity have an influence of the final optical quality. It was also figured out that the gray coloration of the ceramic observed after sintering is caused by the formation of oxygen vacancies, rather than a carbon contamination. Finally, the mode of action of LiF, used as sintering aid to increase optical transmittance, was studied in order to establish reaction mechanisms allowing an optimization of the SPS cycle. This approach helps to reach Er3+:YAG transparent polycrystalline ceramics (Ø = 30 mm, thk = 3 mm) with an optical transmittance of 80 at 400 nm and 84 % at 1100 nm. On the basis of these results and with the help of numerical simulation, an up-scaling of ceramics (Ø = 50 mm, thk = 5 mm) was undertaken in order to evaluate their laser performances through laser cavity tests

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ChiangHsiao und 蕭強. „Fabrication of Nd:YAG transparent polycrystalline ceramics using solvothermal-derived spherical single crystals“. Thesis, 2016. http://ndltd.ncl.edu.tw/handle/zvq737.

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碩士
國立成功大學
資源工程學系
104
A fabrication of Nd:YAG transparent polycrystalline ceramics was reported in this work. Solvothermal derived Nd:YAG powders were used as starting material which were mono- dispersed and spherical single crystals. Highly concentrated slurry for the following slip casting forming was readily formed by a simply sonication treatment without the need of ball milling. To enhance the slurry stability, the parameters of slurry were also investigated. The optimal parameters of the slurry were 50-60 wt. % of solid loading, 2 wt. % of PAA-NH4 as dispersant and treated with an ultrasonic homogenizer for 360 seconds. The green body fabricated using slip casting method was about 60 %. A preheating treatment at 150°C for 1 h was applied to the green body in order to remove the residues. After a sintering at 1800°C for 2 h under N2 atmosphere, dense Nd:YAG polycrystalline ceramics with sintered density of 99.5 % was obtained. .The real in-line transmittance of ceramics was about 30 %.

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Cutler, Paul A. „Synthesis and Scintillation of Single Crystal and Polycrystalline Rare-Earth-Activated Lutetium Aluminum Garnet“. 2010. http://trace.tennessee.edu/utk_gradthes/695.

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Single crystals with composition Lu3Al5O12 were synthesized using Czochralski and micro-pulling-down melt growth techniques. Polycrystalline ceramics of the same composition were synthesized by vacuum annealing of powders prereacted using a citrate-nitrate combustion technique and by spark-plasma-sintering of powders prereacted using a flame-spray-pyrolysis technique. Single crystals and polycrystalline ceramics are activated with Ce3+ or Pr3+ or doubly activated with Ce3+ and Tb3+ ions. Cerium-doped Czochralski-grown single crystals were compared to cerium-terbium codoped Czochralski-grown and micro-pulling down single crystals. Cerium-terbium codoped single crystals are also compared to similarly-activated polycrystalline ceramics sintered under vacuum using combustion-synthesized prereacted powders. X-ray diffraction analysis and fluorescence characterization were used to determine successful formation of single-phase LuAG and successful incorporation of doping species. Absorbance, fluorescence, radioluminescence, and scintillation decay analyses were used to compare synthesis processes and activator selection.

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Buchteile zum Thema "Transparent polycrystalline ceramics"

Huang, Cun Xin, Jian Bao Li, Mu Yun Lei, Hong Bing Du und Xiao Zhan Yang. „Properties and Microstructure of Optically Transparent Polycrystalline Spinel“. In High-Performance Ceramics III, 545–48. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-959-8.545.

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Sung, R. J., T. Kusunose, T. Nakayama, T. Sekino, S. W. Lee und K. Niihara. „Fabrication of Transparent Polycrystalline Silicon Nitride Ceramic“. In Advances in Ceramic Matrix Composites X, 13–21. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118408353.ch2.

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Vu, Mnh, und Richard Haber. „Optimization of the Spark Plasma Sintering Condition for Transparent Polycrystalline Magnesium Aluminate Spinel“. In Advances in Ceramic Armor X, 137–44. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119040590.ch13.

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Villalobos, Guillermo R., Shyam Bayya, Jasbinder S. Sanghera, Michael P. Hunt, Michael K. Cinibulk, Carmen M. Carney, Kristin A. Keller, Bryan M. Sadowski und Ishwar D. Aggarwal. „Development of Transparent Polycrystalline Beta-Silicon Carbide Ceramic using Field Assisted Sintering Technology“. In Advances in Ceramic Armor IX, 109–14. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118807576.ch11.

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Lou, Qihong, Jun Zhou, Yuanfeng Qi und Hong Cai. „Laser Applications of Transparent Polycrystalline Ceramic“. In Advances in Ceramics - Synthesis and Characterization, Processing and Specific Applications. InTech, 2011. http://dx.doi.org/10.5772/17532.

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RHODES, W. H. „Phase Chemistry in the Development of Transparent Polycrystalline Oxides“. In Phase Diagrams in Advanced Ceramics, 1–41. Elsevier, 1995. http://dx.doi.org/10.1016/b978-012341834-0/50002-7.

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Surez, Marta, Adolfo Fernndez, Ramn Torrecillas und Jos L. „Sintering to Transparency of Polycrystalline Ceramic Materials“. In Sintering of Ceramics - New Emerging Techniques. InTech, 2012. http://dx.doi.org/10.5772/35309.

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Konferenzberichte zum Thema "Transparent polycrystalline ceramics"

Ross, Daniel, Yanming Wang, Hadyan Ramadhan und Hitomi Yamaguchi. „Polishing Characteristics of Transparent Polycrystalline YAG Ceramics Using Magnetic Field-Assisted Finishing“. In ASME 2016 11th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/msec2016-8766.

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Transparent polycrystalline yttrium aluminum garnet (YAG) ceramics have garnered an increased level of interest for high-power laser applications due to their ability to be manufactured in large sizes, and doped in relatively substantial concentrations when compared to traditional single-crystalline gain media. However, surface characteristics have a direct effect on the lasing ability of these materials, and a lack of a fundamental understanding of the polishing mechanisms of these ceramics remains a challenge for their utilization. The aim of this paper is to study the polishing characteristics of YAG ceramics using magnetic field-assisted finishing (MAF). An experimental setup was developed, through the refinement of the MAF process, for YAG ceramic workpieces. Using this equipment with diamond abrasives, the YAG ceramic surfaces were polished to sub-nanometer scale. Polishing trials with fine diamond abrasive and colloidal silica were then performed on this sub-nanometer surface and the material removal mechanisms were analyzed. Polishing with 0–0.1 μm diameter diamond abrasive caused increasing roughness with polishing time due to the continuous cycle of relatively substantial chipping followed by minor smoothing. Polishing with colloidal silica caused valleys to widen with increased polishing time and the grain structure of the ceramic influenced the material removal.

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Johnson, J. A., R. Weber, A. I. Kolesnikov und S. Schweizer. „Glass Ceramics for High-Resolution Imaging“. In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-66205.

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Glass-ceramic materials are being developed for use in digital mammography systems. The materials are transparent x-ray storage phosphors, which are potentially less expensive than competing materials with superior performance. The materials do not suffer from loss of resolution and increased noise due to light scattering from grain boundaries, as do the currently available polycrystalline materials. The glass ceramics are based on Eu2+-doped fluorochlorozirconate glasses. These can be heat treated to nucleate Eu-doped barium chloride nanocrystals. The glass ceramic converts ionizing radiation (typically x-rays) into stable electron-hole pairs that can be “read” by scanning a stimulating light beam across the glass to cause photostimulated luminescence (PSL) emission. Measurements on the materials are ongoing to elucidate structure-property relationships developed as a result of introducing rare-earth ions and modifying process conditions. Image quality measurements indicate that the current material competes with state-of-the-art x-ray imaging plates. The paper presents results on structure, properties and future directions of the materials described above.

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Cazamias, J. U. „Dynamic failure of a transparent polycrystalline ceramic“. In Shock compression of condensed matter. AIP, 2000. http://dx.doi.org/10.1063/1.1303548.

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