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Rare Metals 2021年第5期40卷 1307-1316页

作者： Jhonattan De la Roche Juan Manuel Alvarado-Orozco Alejandro Toro Tribology and Surfaces Group Universidad Nacional de ColombiaMedellin 050041Colombia Centro de Ingeniena y Desarrollo Industrial-CIDESI Queretaro 76125Mexico Consorcio de Manufactura Aditiva-CONMAD Queretaro 76125Mexico

The hot corrosion behavior of yttria-stabilized zirconia(YSZ)powder specimens exposed to Na_(2)SO_(4)/V_(2)O_(5) salts mixtures at high temperature was *** tests were carried out at 1000℃ for 10 h,the salt concentrations varied from 0.1 wt%to 1.00 wt%,and the Na_(2)SO_(4)/V_(2)O_(5) mass ratios were between 0.20 and 0.44 following a factorial design 22.X-ray diffraction(XRD)analyses of the tested samples showed with a confidence of95%that the mixture composed of 32 wt%Na_(2)SO_(4)+68 wt%V_(2)O_(5),and 1.00 wt% salt concentration led to high destabilization of the t’-YSZ phase and formation of YVO_(4) products.A second set of experiments were conducted to assess the influence of temperature on the hot corrosion response of the YSZ in the range between 490 and 1100℃.Thermogravimetric analysis(TGA)experiments and Rietveld adjustments of XRD patterns showed that the mass loss of the samples varied with testing temperature and also that the major destabilization of tetragonal phase occurred at 900℃.

关键词： Hot corrosion Molten salts yttria-stabilized zirconia Thermal barrier coatings

Self-supported yttria-stabilized zirconia mesocrystals with tunable mesopores prepared by a chemi-thermal process

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Journal of Materiomics 2019年第3期5卷 350-356页

作者： Leifeng Liu Mirva Eriksson Ji Zou Yuan Zhong Qi Liu Zhi Liu Yu-Lung Chiu Zhijian Shen Department of Materials and Environmental Chemistry Arrhenius LaboratoryStockholm University10691StockholmSweden School of Metallurgy and Materials University of BirminghamB152TTUK Department of Materials Science and Engineering South University of Science and Technology of China518055China Size Materials Co. JiujiangChina

Mesoporous mesocrystals are highly desired in catalysis,energy storage,medical and many other applications,but most of synthesis strategies involve the usage of costly chemicals and complicated synthesis routes,which impede the commercialization of such *** the sintering of dense ceramics,coarsening is an undesirable phenomenon which causes the growth of the grains as well as the pores hence hinders the densification,however,coarsening is desired in the sintering of porous ceramics to expand the pore sizes while retaining the total pore *** we report a chemi-thermal process,during which nanocrystallite aggregates were synthesized by hydrothermal process and then converted to the product by *** this strategy,we synthesized mesoporous self-supported mesocrystals of yttria-stabilized zirconia with tunable pore size and the process was then scaled-up to industrial *** thermal conductivity measurement shows that the mesoporous powder is a good thermal *** monolith pellets can be obtained by SPS sintering under high pressure and the mesoporosity is retained in the monolith *** work features facile and scalable process as well as low cost raw chemicals making it highly desirable in industrial applications.

关键词： Mesocrystal Mesoporous yttria-stabilized zirconia Industry production

Failure mechanisms and surface treatment processes of thermal barrier coatings: Review

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 20-40页

作者： Li, Hao Yang, Shengqiang Li, Xiuhong Li, Wenhui Taiyuan Univ Technol Coll Mech & Vehicle Engn Taiyuan 030024 Peoples R China Taiyuan Univ Technol Shanxi Prov Key Lab Precise Machining Taiyuan 030024 Peoples R China Taiyuan Univ Technol Coll Aeronaut & Astronaut Taiyuan 030024 Peoples R China

Thermal Barrier Coatings (TBCs) technology is key to improving the service temperature and the productivity of aircraft engines. The performance and failure life of TBCs are strongly influenced by surface integrity and microstructure. Therefore, recognizing failure mechanisms and developing effective surface treatment processes are crucial for further improving the reliability and durability of TBCs. This paper explains the primary reasons for TBC failure, emphasizing on how integrity of surface and interface influences interfacial oxidation, high-temperature erosion, and Calcium-Magnesium-Alumina-Silicate (CMAS) corrosion. Furthermore, this paper completely and rigorously evaluates the research status of TBCs surface treatment processes, including the characteristics and effects of various processes, and describes the requirements and goals of pretreatment and post-treatment. In addition, a potential direction for the development and application of TBCs surface treatment is suggested. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Thermal Barrier Coatings (TBCs) Failure Surface treatment processes Processing goals Mass finishing HOT CORROSION BEHAVIOR yttria-stabilized zirconia HIGH-TEMPERATURE OXIDATION ELECTRON-BEAM CMAS CORROSION EROSION BEHAVIOR HEAT-TREATMENT GROWN OXIDE STRESS-DISTRIBUTION ADHESION STRENGTH

Recent progress in thermal/environmental barrier coatings and their corrosion resistance

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Rare Metals 2020年第5期39卷 498-512页

作者： Hong-Fei Chen Chi Zhang Yu-Chen Liu Peng Song Wen-Xian Li Guang Yang Bin Liu School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Institute of Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

Thermal/environmental barrier coatings(T/EBCs)play important roles in jet and/or gas turbine engines to protect the Ni-based superalloys and/or ceramic matrix composite substrates from the high-temperature airflow *** efforts have been contributed to searching for enhanced T/EBC materials to improve the efficiency of the engines,which is the key of improving thrust-to-weight ratio and energy *** practical candidates,rare earth-contained materials,are widely used for T/EBCs in gas turbines due to their excellent properties such as low thermal conductivity,high melting point,hightemperature strength and durability as exhibited in yttriastabilized zirconia,pyrochlore oxides and rare earth *** addition to the intrinsic properties,the microstructures obtained by different synthesis processes and the service performances,as well as the underlying failure mechanism,are also significant to this specific ***,the main challenges for T/EBCs developments are T/EBC materials selection with balanced properties and their anti-corrosion performances at higher operating *** this review,we summarized the progress in their fabrication techniques and mechanical/thermal properties of typically rare earth-contained T/EBCs,together with their anti-corrosion performance under the condition of molten salts or oxides(such as Na2SO4,V2O5and NaVO3),calcium–magnesium–alumina–silicate(CMAS)and high-temperature water vapor.

关键词： Thermal/environmental barrier coatings yttria-stabilized zirconia Rare earth zirconates Rare earth silicates Corrosion resistance

A review of C_1 chemistry synthesis using yttrium-stabilized zirconia catalyst

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Journal of Rare Earths 2008年第1期26卷 1-6页

作者： Antonius Indarto Jae-Wook Choi Hwaung Lee Hyung Keun Song Plasma-Catalyst Chemical Process

C1 chemistry based on synthesis gas, methane, and carbon dioxide offers many routes to industrial chemicals. The reactions related to the synthesis of gas can be classified into direct and indirect approach for making such products, such as acetic acid, dimethyl ether, and alcohol. Catalytic syngas processing is currently done at high temperatures and pressures, conditions that could be unfavorable for the life of the catalyst. Another issue of C1 chemistry is related to the methane-initiated process. It has been known that direct methane conversions are still suffering from low yields and selectivity of products resulting in unprofitable ways to produce products, such as higher hydrocarbons, methanol, and so on. However, many experts and researchers are still trying to find the best method to overcome these barriers, for example, by finding the best catalyst to reduce the high-energy barrier of the reactions and conduct only selective catalyst-surface reactions. The appli- cation of yttria-stabilized zirconia （YSZ） and its combination with other metals for catalyzing purposes are increasing. The existence of an interesting site that acts as oxygen store could be the main reason for it. Moreover, formation of intermediate species on the surface of YSZ also contributes significantly in increasing the production of some specific products. Understanding the phenomena happening inside could be necessary. In this article, the use of YSZ for some C1 chemistry reactions was discussed and reviewed.

关键词： C1 chemistry methane synthesis gas methanol yttria-stabilized zirconia catalyst oxygen storage rare earths

Solid oxide membrane-assisted electrolytic reduction of Cr_(2)O_(3) in molten CaCl_(2)

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International Journal of Minerals,Metallurgy and Materials 2020年第12期27卷 1626-1634页

作者： Bo Wang Chao-yi Chen Jun-qi Li Lin-zhu Wang Yuan-pei Lan Shi-yu Wang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving Guiyang 550025China

Solid oxide membrane-assisted electrolytic reduction of solid Cr_(2)O_(3) to Cr in molten CaCl_(2) was performed using a sintered porous Cr_(2)O_(3) cathode paired with an yttria-stabilized zirconia(YSZ)tube anode containing carbon-saturated liquid copper *** of the reduction mechanism,ion migration behavior,and effects of cathode pellet porosity and particle size on the electrolysis products and reduction rate revealed that the cathode microstructure and electrolytic conditions were key factors influencing the electrolysis *** results were obtained when the cathode was characterized by high porosity and a small particle size because this combination of features contributed to ion *** electrochemical activation was observed when cathode pellets prepared by 4 MPa molding followed by 2 h of sintering at 1150℃ were *** electrode reduction process(Cr^(3+)→Cr^(2+)→Cr)was promoted by high electrode voltages,and Cr metal was efficiently *** proposed method appears to be well suited for electrolytic Cr production because it does not require expensive pre-electrolysis techniques or generate harmful by-products.

关键词： solid oxide membrane yttria-stabilized zirconia electrometallurgy chromium molten salt

Low-Cost Fabrication for ZrO_2-Based Electrolyte Thin-Substrate by Aqueous Gel-Casting

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Journal of Rare Earths 2004年第4期22卷 514-516页

作者：刘晓光李国军仝建峰陈大明 National Key Laboratory of Advanced Composites Beijing Institute of Aeronautical Materials Beijing 100095 China

The possibility to fabricate yttria-stabilized zirconia (YSZ) thin-substrates by aqueous gel casting of high concentrated aqueous slurries was investigated. The effects of dispersant, pH value, and solid content of slurries for gel process on stability and viscosity of slurries were optimized. YSZ thin-substrates green bodies with 100 μm thickness and 100 mm×100 mm flat plate were fabricated. Microstructure observations, density and bending measurements show that these green bodies are homogeneous and highly densified. After sintering at 1873 K×2 h, the ionic conductivity reaches 0.155 S·cm^(-1) at 1273 K.

关键词： yttria-stabilized zirconia thin-substrates aqueous slurries ionic conductivity rare earths

Relationship between lattice mismatch and ionic conduction of grain boundary in YSZ

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Progress in Natural Science:Materials International 2014年第1期24卷 83-86页

作者： Fei Ye Chunyu Yin Dingrong Ou Toshiyuki Mori School of Materials Science and Engineering Dalian University of Technology Key Laboratory of Materials Modification by Laser Ion and Electron BeamsDalian University of TechnologyMinistry of Education Laboratory of Fuel Cells Dalian Institute of Chemical PhysicsChinese Academy of Sciences Fuel Cell Materials Group Battery Materials UnitNational Institute for Materials Science

The grain boundary plays an important role in the electrical behaviors of solid oxide electrolytes for solid state fuel cells. To reveal the relationship between the structure and the ionic conductivity of grain boundary,the conductive properties of {1 1 1} and {1 1 0} twist grain boundaries in 8 mol% yttria-stabilized zirconia have been examined. These boundaries have a series of Σ values defined by the coincident site lattice model. It has been found that the activation energy of {1 1 1} twist grain boundary increases and then decreases with the Σ value,while that of the {1 1 0} boundary shows an opposite trend. It is suggested that the properties can reflect the balance of the effects of lattice mismatch on the diffusion ability of oxygen vacancies and the segregation of oxygen vacancies and Y3 tions. Therefore,the properties in polycrystalline electrolyte can be adjusted by controlling the grain boundary structures.

关键词： yttria-stabilized zirconia Grain boundary Ionic conduction Mismatch

YBCO Films Grown on Sapphire with YSZ Buffer Layer

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Rare Metals 1994年第4期13卷 269-272页

作者：石东奇杨秉川王小平彭正顺常世安北京有色金属研究总院北京

The (h00) oriented YSZ (yttria-stabilized zirconia) buffer layers were grown successfully on (1120) and(1102) sapphire plane substrates by rf. planar target magnetron sputtering method. The effect of different dep-osition conditions on the structure of YSZ films was studied X-ray diffraction rock curve and electron channel-ling pattern (ECP) showed that the YSZ films has highly oriented nature. YBCO (Y BaCuO) films were depos-ited on the YSZ / (1120) Al_2O_3 and (1102) Al_2O_3, substrate by in situ de inverted cyhdrical target magnetronsputtering method. T_c≥88K and J_c=1O × 10￣6A / cm￣2 at 77 K were achieved

关键词： YBaCuO film yttria-stabilized zirconia Buffer layer

A Study of Plaque Adhesion during Implant Treatment of Missing Molars

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Open Journal of Stomatology 2022年第3期12卷 96-102页

作者： Yuka Hasegawa Yu Kishimoto Yasunori Kanemitsu Toshiichiro Tanabe Kuniteru Nagahara Tetsuji Nakamoto Department of Maxillofacial Implant School of Dentistry Asahi University Mizuho Japan Medical and Dental Center Asahi University Mizuho Japan

Purpose: In implant treatment, the abutments and superstructures form a transmucosal area. In addition to providing appropriate cleaning instructions to patients, its material properties must be carefully considered. It is not clear how much plaque adhesion occurs at each site during treatment process, and the effect of materials on plaque adhesion. Methods: In this study, 33 patients, 13 maxillary cases and 20 mandibular cases, who had implants placed in the missing molars were evaluated for the plaque adhesion of provisional restorations made of acrylic resin and monolithic zirconia final restoration after a period of more than 4 weeks. In addition, oral hygiene instructions were thoroughly given for 12 cases at the time of staining after the provisional restorations, and re-evaluated in 4 weeks. Results: About 20% of the buccal-lingual area of the prosthetic device fabricated with acrylic resin showed plaque staining, whereas about 40% of the area of the mesial and distal. On the other hand, for the zirconia final restorations, the percentage of staining was about 5% for buccal and lingual surface and 10% for mesial and distal surface. The stained area ratio of the provisional restoration correlated with the zirconia superstructure area ratio. Even with careful oral hygiene, it became clear that the amount of plaque adhesion due to the difference in materials could not be overcome. Conclusion: The zirconia superstructure is extremely good from the viewpoint of plaque adhesion, but cases with a large stained area at the time of provisional restoration should be carefully followed up.

关键词： Superstructure Dental Plaque yttria-stabilized zirconia Polymethyl Methacrylate