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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 73-79页

作者： Ru-qin Gao Qian Sun Zhi Fang Guo-ting Li Meng-zhe Jia Xin-mei Hou School of Environmental Science and Engineering North China University of Water Resources and Electric Power Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing

Diatomite-based porous ceramics were adopted as carriers to immobilize nano-TiO2 via a hydrolysis-deposition technique. The thermal degradation of as-prepared composites was investigated using thermogravimetric-differential thermal analysis, and the phase and microstructure were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. The results indicated that the carriers were encapsulated by nano-TiO2 with a thickness of 300-450 nm. The main crystalline phase of TiO2 calcined at 650~C was anatase, and the average grain size was 8.3 nm. The FT-IR absorption bands at 955.38 cm1 suggested that new chemical bonds among Ti, O, and Si had formed in the composites. The photocatalytic （PC） activity of the composites was investigated un- der UV irradiation. Furthermore, the photodegradation kinetics of formaldehyde was investigated using the composites as the cores of an air cleaner. A kinetics study showed that the reaction rate constants of the gas-phase PC reaction of formaldehyde were k = 0.576 mg＇m3·min^-1 and K = 0.048 m3/mg.

关键词： nano titanium dioxide/diatomite porous ceramics hydrolysis precipitation photocatalytic activity kinetic equation formaldehyde degradation

High wave transmittance and low thermal conductivity Y-a-SiAlON porous ceramics for high-temperature radome applications

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Journal of Advanced ceramics 2023年第6期12卷 1273-1287页

作者： Runwu Yang Jie Xu Jia Guo Xuanyu Meng Ping Zhang Fengying Fan Yanan Qu Feng Gao State Key Laboratory of Solidification Processing MIIT Key Laboratory of Radiation Detection Materials and DevicesSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China NPU-QMUL Joint Research Institute of Advanced Materials and Structure Northwestern Polytechnical UniversityXi'an 710072China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

With the development of hypersonic vehicle technology,ceramic-based radome materials are highly demanded due to their high operating temperatures,good dielectric properties,and high mechanical ***α-SiAlON is an ideal material for radome applications,its intrinsic low transmittance and high thermal conductivity limit its ***,we prepared Y-α-SiAlON porous ceramics through tert-butanol(TBA)gel-casting using the self-synthesizedα-SiAlON *** Y-α-SiAlON porous ceramics exhibited a uniform micron-level connected pore structure with the porosity(P)of 44.2%-58.6%.The real part of permittivity(s')was 3.13-4.18(8.2-12.4 GHz),which decreased significantly with the increasing *** wave transmittance(|T|^(2))of the sample with porosity of 58.6%could exceed 80%in the thickness range of 6-10 *** thermal conductivity was maintained at a low level of 1.38-2.25 W·m^(-1)·K^(-1) owing to the introduction of the pore *** flexural strength was 44.73-88.33 MPa,which may be increased by rod-likeα-SiAlON *** results indicate that the prepared Y-α-SiAlON porous ceramics meet the requirements of high-temperature wave-transmitting materials for radome applications.

关键词： a-SiAlON porous ceramics wave-transmittance materials thermal conductivity flexural strength

Preparation and characterization of porous ceramics prepared by kaolinite gangue and Al(OH)_3 with double addition of MgCO_3 and CaCO_3

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 450-454页

作者： Wen Yan Nan Li Bing-qiang Han The Key State Laboratory Breeding Base of Refractories and ceramics Wuhan University of Science and Technology Wuhan 430081 China

porous ceramics were prepared from kaolinite gangue and Al（OH）3 with double addition of MgCO3 and CaCO3 by the pore-forming in-situ *** characterizations of porous ceramics were investigated by X-ray diffractometry,scanning electron microscopy,and mercury porosimetry measurements,*** is found that although the decomposition of MgCO3 and CaCO3 has little contribution to the porosity,the double addition of MgCO3 and CaCO3 strongly affects the formation of liquid phase,and then changes the phase compositions,pore characterization,and *** appropriate mode is the sample containing 1.17wt% MgCO3 and 1.17wt% CaCO3,which has high apparent porosity（41.0%）,high crushing strength（53.5 MPa）,high mullite content（76wt%）,and small average pore size（3.24 μm）.

关键词： porous ceramics characterization kaolinite aluminum hydrxide additives

Al2O3-TiO2/ZrO2-SiO2 based porous ceramics from particle-stabilized wet foam

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Journal of Advanced ceramics 2017年第2期6卷 129-138页

作者： Bijay BASNET Naboneeta SARKAR Jung Gyu PARK Sangram MAZUMDER Ik Jin KIM Institute of Processing and Application of Inorganic Materials(PAIM) Hanseo University # 360 Seosan-siChungnam 356-706 Republic of Korea School of Mechanical and Materials Engineering Washington State University Pullman Washington United States

The porous ceramics based on Al2O3-TiO2/ZrO2-SiO2 from particle-stabilized wet foam by direct foaming were *** initial Al2O3-TiO2 suspension was prepared by adding TiO2 suspension to partially hydrophobized colloidal Al2O3 suspension with equimolar amount,to form Al2TiO5 on *** secondary ZrO2-SiO2 suspension was prepared using the equimolar composition,and to obtain ZrSiO4,ZrTiO4,and mullite phases in the sintered samples,the secondary suspension was blended into the initial suspension at 0,10,20,30,and 50 vol％.The wet foam exhibited an air content up to 87％,Laplace pressure from 1.38 to 2.23 mPa,and higher adsorption free energy at the interface of approximately 5.8×108 to 7.5×108J resulting an outstanding foam stability of 87％.The final suspension was foamed,and the wet foam was sintered from 1400 to 1600 ℃ for 1 *** porous ceramics with pore size from 150 to 400 μm on average were *** phase identification was accomplished using X-ray diffraction (XRD),differential thermal analysis (DTA),and thermogravimetric analysis (TGA),and microstructural analysis was performed using field emission scanning electron microscopy (FESEM).

关键词： Al2TiO5 direct foaming Laplace pressure adsorption free energy porous ceramics

Constructing Straight Pores and Improving Mechanical Properties of GangueBased porous ceramics

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Journal of Renewable Materials 2021年第12期9卷 2129-2141页

作者： Hang Xu Huiling Du Le Kang Qiudi Cheng Danni Feng Siyu Xia School of Materials Science and Engineering Xi’an University of Science and TechnologyXi’an710054China

The large-scale accumulation and pollution of solid mining waste is an urgent *** gangue is a prominent type of solid waste,and shows promise for use in high value-added products due to its content of many important compounds,including SiO_(2) and *** study proposed the preparation of highly porous ceramics from coal gangue,coal slime,and coconut palm *** ceramics were produced at a sintering temperature of 950℃ with a fiber content of 6 wt%,which led to the formation of porous ceramics with a porosity of 66.93%,volume density of 1.0329 g/cm^(3),compressive strength of 1.1025 MPa,and thermal conductivity is 0.3919 K(W/mk).A finite element model of the porous ceramics was established using the Abaqus module in ANSYS software,where the stress distribution and compressive strength were ***,the relationship between porosity and compressive strength was *** thermal properties of the porous ceramics were analyzed using the Fluent module,where the simulated changes in porosity under various sintering temperatures were consistent with the experimental *** preparation of this highly porous ceramic from solid waste coal gangue shows promise for the minimizing the impact of waste gas and wastewater pollution in the future.

关键词： Coal gangue porous ceramics mechanical properties thermal properties

A Novel Approach for the Effective Thermal Conductivity of porous ceramics

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Chinese Journal of Aeronautics 2006年第B12期19卷 244-247页

作者： ZHU Qiang ZHANG Fan-wei ZHANG Yue ZHANG Da-hai LI Zhong-ping School of Materials Science and Engineering Beijing University of .4eronautics and Astronautics Beijing 100083 China National Key Laboratory of Advanced Functional Composite Materials Aerospace Research Institute of Materials and Processing Technology Beijing 100076China

A new approach in combination of the effective medium theory with the equivalent unit in numerical simulation was developed to study the effective thermal conductivity of porous ceramics. The finite element method was used to simulate the heat transfer process which enables to acquire accurate results through highly complicated modeling and intensive computation. An alternative approach to mesh the material into small cells was also presented. The effective medium theory accounts for the effective thermal conductivity of cells while the equivalent unit is subsequently applied in numerical simulation to analyze the effective thermal conductivity of the porous ceramics. A new expression for the effective thermal conductivity, allowing for some structure factors such as volume fraction of pores and thermal conductivity, was put forward, and the results of its application was proved to be close to those of the mathematical simulation.

关键词： effective thermal conductivity porous ceramics equivalent unit numerical simulation

Research of Microstructure,Phase,and Mechanical Properties of Aluminum-Dross-Based porous ceramics

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Journal of Renewable Materials 2023年第7期11卷 3057-3072页

作者： Liang Yu Yuan Liu Xiuling Cao Yulong Yan Chen Zhang Yanli Jiang Key Laboratory of New Processing Technology for Nonferrous Metals&Materials Guilin University of TechnologyGuilin541004China Guangxi Scientific Experiment Center of Mining Metallurgy and EnvironmentGuilin University of TechnologyGuilin541004China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources Guilin University of TechnologyGuilin541004China Hebei Technology Innovation Center for Intelligent Development and Control of Underground Built Environment School of Exploration Technology and EngineeringHebei GEO UniversityShijiazhuang050031China

In this study,the effect of sintering temperature and the addition of kaolin,a sintering agent,on the microscopic,phase,and mechanical properties of ceramics were investigated using secondary aluminum dross(SAD)as the main component in the manufacturing of *** basic phases of the ceramics were Al_(2)O_(3),MgAl_(2)O_(4),NaAl_(11)O_(17),and SiO_(2)without the addition of *** diffraction peaks of MgAl_(2)O_(4),NaAl_(11)O_(17),and SiO_(2)kept decreasing while those of Al_(2)O_(3)kept increasing with an increase in *** addition,the increase in temperature promoted the growth of the *** grains were uniform in size and regular in distribution,with a shrinkage of 2.2%,porosity of 72.5%,bulk density of 1.076 g/cm^(3),and compressive strength of 1.12 *** the sintering temperature was 1450°C,the basic phases of the ceramic after the addition of kaolin were Al_(2)O_(3),MgAl_(2)O_(4),NaAl_(11)O_(17),and SiO_(2).With the increase of kaolin,the diffraction peaks of NaAl_(11)O_(17)and SiO_(2)decreased until they disappeared,while the diffraction peaks of Al_(2)O_(3)increased *** kaolin was added at 30 wt.%,the ceramics obtained had shrinkage of 18%,a porosity of 47.26%,a bulk density of 1.965 g/cm^(3),and compressive strength of 31.9 *** existed inside the ceramics without the addition of kaolin,while the addition of kaolin significantly changed this *** is shown that SAD can obtain porous ceramics with good properties at a sintering temperature of 1450°C and a kaolin addition of 30 wt.%.

关键词： Secondary aluminum dross porous ceramics microstrure phase mechanical properties

Research Progress on Thermal Shock Behavior of porous ceramics

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China's Refractories 2022年第1期31卷 24-29页

作者： YAN Mingwei LIU Kaiqi ZHANG Jiayu SUN Guangchao LI Xiang SI Kaikai State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100019China University of Chinese Academy of Sciences Beijing 100049China

Thermal-mechanical coupling effect causes a large stress within porous ceramics at high temperatures,resulting in strength attenuation and product reliability *** shock resistance is one of the key factors to characterize the reliability of ceramic materials under thermal-mechanical coupling *** is important to study the thermal shock resistance of the porous ceramics to evaluate their service performance and improve their service *** better evaluate the effect of the thermal shock resistance on properties of the porous ceramics,the evaluation theories,experimental characterization methods and influencing factors about the thermal shock performance of the porous ceramics were reviewed in this paper,and some future research directions were prospected.

关键词： porous ceramics thermal-mechanical coupling thermal shock resistance evaluation theory influence factor

Progress in Preparation Technology of porous ceramics for High Temperature Dust Filtration

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China's Refractories 2023年第4期32卷 42-51页

作者： ZHANG Keke QIN Feng YAN Miaoxin LIU Shijie LI Xuhao GUO Yusen WANG Li YIN Chaofan DONG Binbin School of Materials Science and Engineering Luoyang Institute of Science and TechnologyLuoyang471023China

With the rapid industrialization and urbanization,the demand for air quality management is more and more *** temperature dust filtration is one important environmental management *** ceramics are used as filter materials in the field of high-temperature dust filtration because of their unique advantages such as high filtration efficiency,as well as high temperature stability,particle loss resistance,corrosion resistance and *** paper mainly introduced several common preparation techniques of porous ceramics,including the traditional organic foam impregnation method,foaming method,in-situ combustion method,pore-forming method and other new methods such as the template method,gel injection molding method,freeze-drying method,multi-component co-precipitation method and hydrogel *** principle,advantages and disadvantages of these preparation technologies and their research status were *** application of these technologies in the field of high temperature dust filtration was briefly ***,the application prospect of the porous ceramics in the field of high temperature dust filtration was prospected.

关键词： high temperature smoke dust filtration porous ceramics porosity removal rate

Preparation and characterization of the porous ceramics from fly ash

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Journal of Coal Science & Engineering(China) 2007年第1期13卷 95-98页

作者：任祥军张学斌孟广耀刘杏芹 Department of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China Hefei Coal Science Research Institute Hefei 230001 China

porous ceramics was made from coal fly ash, and the microstructure and other properties were characterized as a function of the amount of the pore-forming agent and firing temperature. The results indicated that the proper sintering temperature for the useful ceramic materials is 1 250℃, and a liquid-phase was involved in the densification process.

关键词： fly ash porous ceramics pore-forming agent porosity permeability