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Ultra-high Temperature Ceramic Coatings:A Review on Preparation Technology and Development Prospect
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作者 LIU Shijie WANG Li +7 位作者 DONG Binbin XU Biao GUO Yusen MIN Yongchao GUO Yanyan WEI Haoyu ZHANG Keke YIN Chaofan 《China's Refractories》 CAS 2023年第3期42-49,共8页
Ultra-high temperature ceramic coatings have ultra-high melting points,excellent mechanical properties and high temperature ablation resistance.These unique performance combinations turn it into a promising material f... Ultra-high temperature ceramic coatings have ultra-high melting points,excellent mechanical properties and high temperature ablation resistance.These unique performance combinations turn it into a promising material for use in extreme environment structures in rockets and hypersonic vehicles,particularly nozzles,leading edges and engine components.In this paper,various preparation methods of ultra-high temperature ceramic coatings were reviewed,including plasma spraying,chemical vapor deposition,pack cementation,slurry sintering,hot pressing and their research progress.Meanwhile,some new preparation methods of high temperature coatings,such as ion beam deposition,ultrasonic spraying,metal organic frame work coating,and magnetron sputtering,were introduced.The development trend of ultra-high temperature coatings was prospected as well. 展开更多
关键词 ultra-high temperature coating preparation process development prospect
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DIRECTIONALLY SOLIDIFIED MICROSTRUCTURE OF AN ULTRA-HIGH TEMPERATURE Nb-Si-Ti-Hf-Cr-Al ALLOY 被引量:15
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作者 P.Guan X.P.Guo +3 位作者 X.Ding J.Zhang L.M.Gao K. Kusabiraki 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第4期450-454,共5页
The directionally solidified samples of an ultra-high temperature Nb-Si-Ti-Hf-Cr-Al alloy have been prepared with the use of an electron beam floating zone melting (EBFZM) furnace, and their microstructural characteri... The directionally solidified samples of an ultra-high temperature Nb-Si-Ti-Hf-Cr-Al alloy have been prepared with the use of an electron beam floating zone melting (EBFZM) furnace, and their microstructural characteristics have been analyzed. All the primary dendrites of Nb solid solution (Nbss), eutectic colonies of Nba, plus (Nb, Ti)3 Si/(Nb, Ti)5 Si3 and chains of (Nb, Ti)3 Si/(Nb, Ti)5 Si3 plates align along the growth direction of the samples. With increasing of the withdrawing rate, the microstructure is refined, and the amounts of Nbss+ (Nb, Ti)3 Si/(Nb, Ti)5 Si3 eutectic colonies and (Nb, Ti)3 Si/(Nb, Ti)5 Si3 plates increase. There appear nodes in the (Nb, Ti)3 Si/(Nb, Ti)5 Si3 plates. 展开更多
关键词 ultra-high temperature alloy Nb-Si based alloy in situ composite unidirectional solidification microstructural evolution
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The temperature-dependent fracture strength model for ultra-high temperature ceramics 被引量:14
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作者 Weiguo Li Fan Yang Daining Fang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第2期235-239,共5页
Breaking down the entire structure of a material implies severing all the bonds between its atoms either by applying work or by heat transfer. Because bond-breaking is indifferent to either means, there is a kind of e... Breaking down the entire structure of a material implies severing all the bonds between its atoms either by applying work or by heat transfer. Because bond-breaking is indifferent to either means, there is a kind of equivalence between heat energy and strain energy. Based on this equivalence, we assume the existence of a constant maximum storage of energy that includes both the strain energy and the corresponding equivalent heat energy. A temperaturedependent fracture strength model is then developed for ultrahigh temperature ceramics (UHTCs). Model predictions for UHTCs, HfB2, TiC and ZrB2, are presented and compared with the experimental results. These predictions are found to be largely consistent with experimental results. 展开更多
关键词 ultra-high temperature ceramics · Equivalent energy · Critical failure energy · Strength model
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SIMULATION OF TEMPERATURE FIELD IN ULTRA-HIGH FREQUENCY INDUCTION HEATING AND VERIFICATION 被引量:2
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作者 李奇林 徐九华 苏宏华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第2期155-161,共7页
An experimental and numerical study on the temperature field induced in the ultra-high frequency induction heating is carried out.With an aim of predicting the thermal history of the workpiece,the influence factors of... An experimental and numerical study on the temperature field induced in the ultra-high frequency induction heating is carried out.With an aim of predicting the thermal history of the workpiece,the influence factors of temperature field,such as the induction frequency,the dimension of coil and the gap between coil and workpiece,are investigated considering temperature-dependent material properties by using FLUX 2Dsoftware.The temperature field characteristic in ultra-high induction heating is obtained and discussed.The numerical values are compared with the experimental results.A good agreement between them is observed with 7.9% errors. 展开更多
关键词 ultra-high frequency induction heating temperature field FLUX 2Dsoftware
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Fabrication and Thermal Structural Characteristics of Ultra-high Temperature Ceramic Struts in Scramjets 被引量:2
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作者 解维华 PENG Zujun +2 位作者 金华 孟松鹤 PAN Yu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第2期375-380,共6页
ZrB_2-SiC based ultra-high temperature ceramic(UHTC) struts were firstly proposed and fabricated with the potential application in the combustor of scramjets for fuel injection and flame-holding for their machinabil... ZrB_2-SiC based ultra-high temperature ceramic(UHTC) struts were firstly proposed and fabricated with the potential application in the combustor of scramjets for fuel injection and flame-holding for their machinability and excellent oxidation/ablation resistance in the extreme harsh environment. The struts were machined with electrospark wire-electrode cutting techniques to form UHTC into the desired shape, and with laser drilling to drill tiny holes providing the channels for fuel injection. The integrated thermal-structural characteristic of the struts was evaluated in high-temperature combustion environment by the propane-oxygen free jet facility, subject to the heat flux of 1.5 MW/m^2 lasting for 300 seconds, and the struts maintained integrity during and after the first experiment. The experiments were repeated for verifying the reusability of the struts. Fracture occurred during the second repeated experiment with the crack propagating through the hole. Finite element analysis(FEA) was carried out to study the thermal stress distribution in the UHTC strut. The simulation results show a high thermal stress concentration occurs at the hole which is the crack initiation position. The phenomenon is in good agreement with the experimental results. The study shows that the thermal stress concentration is a practical key issue in the applications of the reusable UHTC strut for fuel injection structure in scramjets. 展开更多
关键词 ultra-high temperature ceramic(UHTC) strut thermal stress fracture scramjet
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Rapid Directional Solidification with Ultra-High Temperature Gradient and Cellular Spacing Selection of Cu-Mn Alloy
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作者 SenYANG YunpengSU +2 位作者 WenjinLIU WeidongHUANG YaoheZHOU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第3期225-228,共4页
The detailed laser surface remelting experiments of Cu-31.4 wt pct Mn and Cu-26.6 wt pct Mn alloys on a 5 kW CO2 laser were carried out to study the effects of processing parameters (scanning velocity, output power of... The detailed laser surface remelting experiments of Cu-31.4 wt pct Mn and Cu-26.6 wt pct Mn alloys on a 5 kW CO2 laser were carried out to study the effects of processing parameters (scanning velocity, output power of laser) on the growth direction of microstructure in the molten pool and cellular spacing selection under the condition of ultra-high temperature gradient and rapid directional solidification. The experimental results show that the growth direction of microstructure is strongly affected by laser processing parameters. The ultra-high temperature gradient directional solidification can be realized on the surface of samples during laser surface remelting by controlling laser processing parameters, the temperature gradient and growth velocity can reach 106 K/m and 24.1 mm/s, respectively, and the solidification microstructure in the center of the molten pool grows along the laser beam scanning direction. There exists a distribution range of cellular spacings under the laser rapid solidification conditions, and the average spacing decreases with increasing of growth rate. The maximum, λmax, minimum, λmin, and average primary spacing, A, as functions of growth rate, Vb, can be given by,λmax=12.54Vb-0.61, λmin=4.47 Vb-0.52, λ=9.09Vb-0.62, respectively. The experimental results are compared with the current Hunt-Lu model for rapid cellular/dendritic growth, and a good agreement is found. 展开更多
关键词 Laser surface remelting ultra-high temperature gradient Cellular spacing Cu-Mn alloys
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Temperature Effect on the Conformation Transition of Ultra-high Molecular Weight Polyethylene/Polypropylene Blends Undergoing Continuous Volume Extensional Flow:A Mesoscopic Simulation
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作者 WANG Junxia YAN Shilin YU Dingshan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第3期540-545,共6页
Due to the multiformity and complexity of chain conformation under external flow and the challenge of systematically investigating the transient conformation and dynamic evolution process of polymer chains at the mole... Due to the multiformity and complexity of chain conformation under external flow and the challenge of systematically investigating the transient conformation and dynamic evolution process of polymer chains at the molecular level by means of present experimental techniques,a universal description of both chain conformation and dynamics with respect to continuous volume extensional flow(CVEF)is still absent.Taking into account the temperature effect,we performed dissipative particle dynamics(DPD)simulations with the particles corresponding to the repeat units of polymers over a wide temperature range and analyzed the correlation with the conformational properties of ultra-high molecular weight polyethylene/polypropylene(UHMWPE/PP)blend in response to the CVEF.With time evolution,the polymer chains become highly oriented parallel to the flow direction instead of the initial random coiling and self-aggregation.It is found that a high temperature is necessary for more substantial compactness to take place than low temperature.The low-k plateau and low-k peak in structure factor S(k)curves suggest a low degree of conformational diversity and a high degree of chain stretching.It is also concluded that the intra-molecular C-C bond interaction is the main driving force for the dynamics process of the chain conformations undergoing CVEF,where the motion of the alkyl chains is seriously restricted owing to the increase in bond interaction potential,resulting in a reduction of the difference in diffusion rates among alkyl chains. 展开更多
关键词 temperature effect dissipative particle dynamics ultra-high molecular weight polyethylene POLYPROPYLENE volume extensional flow chain conformation BLENDS
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Effects of mechanical boundary conditions on thermal shock resistance of ultra-high temperature ceramics
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作者 Tianbao CHENG Weiguo LI +2 位作者 Yushan SHI Wei LU Daining FANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第2期201-210,共10页
The effects of mechanical boundary conditions, often encountered in thermalstructural engineering, on the thermal shock resistance(TSR) of ultra-high temperature ceramics(UHTCs) are studied by investigating the TS... The effects of mechanical boundary conditions, often encountered in thermalstructural engineering, on the thermal shock resistance(TSR) of ultra-high temperature ceramics(UHTCs) are studied by investigating the TSR of a UHTC plate with various types of constraints under the first, second, and third type of thermal boundary conditions. The TSR of UHTCs is strongly dependent on the heat transfer modes and severity of the thermal environments. Constraining the displacement of the lower surface in the thickness direction can significantly decrease the TSR of the UHTC plate, which is subject to the thermal shock at the upper surface. In contrast, the TSR of the UHTC plate with simply supported edges or clamped edges around the lower surface is much better. 展开更多
关键词 thermal shock resistance(TSR) ultra-high temperature ceramic(UHTC) mechanical boundary condition temperature-dependent material property thermal environment
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Porous Ultra-high Temperature Ceramics for Ultra-high Temperature Thermal Protection System
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作者 LI Fei LIU Jixuan ZHANG Guojun 《China's Refractories》 CAS 2020年第4期23-28,共6页
Ultra-high temperature ceramics(UHTCs)are a family of borides,carbides and nitrides of transition elements such as hafnium,zirconium,tantalum and niobium.They exhibit the highest known melting points,good mechanical s... Ultra-high temperature ceramics(UHTCs)are a family of borides,carbides and nitrides of transition elements such as hafnium,zirconium,tantalum and niobium.They exhibit the highest known melting points,good mechanical strength,good chemical and thermal stability under certain conditions.In last decade,researchers dedicated to characterize porous UHTCs aiming to develop novel thermal insulating materials that could withstand temperatures over 2000℃.In this article,the preparation and characteristics of porous UHTCs were reviewed.Dry processing,colloidal processing and solution processing routes have been used to prepare porous UHTCs with porosities ranging from 5%to 97%and pore sizes ranging from hundreds of nanometers to hundreds of micrometers.The obtained porous UHTCs are chemically and dimensionally stable at temperatures up to 2000℃ during static state high-temperature thermal aging. 展开更多
关键词 ultra-high temperature ceramics porous ceramics thermal protection system extreme environments
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“Low Creep Ultra-high Temperature Corundum Mullite Kiln Furnature” Developed by Sinosteel LIRR Rewarded as “National New Product”
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《China's Refractories》 CAS 2012年第4期12-12,共1页
Recently, " Low Creep Ultra-high Temperature Corundum Mullite Kiln Fumature" developed by Sinosteel L1RR was listed in The National New Product Program in 2012 of The Ministry of Science and Technology of China.
关键词 high Low Creep ultra-high temperature Corundum Mullite Kiln Furnature
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Ultra-High Temperature Gratings
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作者 John Canning Somnath Bandyopadhyay +1 位作者 Michael Stevenson Kevin Cook 《Journal of Electronic Science and Technology of China》 2008年第4期420-422,共3页
Regenerated gratings seeded by type-I gratings are shown to withstand temperatures beyond 1000 ℃. The method of regeneration offers a new approach to increasing temperature resistance of stable fibre Bragg and other ... Regenerated gratings seeded by type-I gratings are shown to withstand temperatures beyond 1000 ℃. The method of regeneration offers a new approach to increasing temperature resistance of stable fibre Bragg and other gratings. These ultra-high temperature (UHT) gratings extend the applicability of silicate based components to high temperature applications such as monitoring of smelters and vehicle and aircraft engines to high power fibre lasers. 展开更多
关键词 ANNEALING Bragg gratings regenerated gratings temperature sensing ultra-high temperature.
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Emergent ultra-high temperature ferromagnetism in La_(2)CoO_(4±x) thin films
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作者 Ziang Meng Han Yan +13 位作者 Peixin Qin Zhuo Yin Peiheng Jiang Xiaorong Zhou Xiaoning Wang Hongyu Chen Li Liu Zhiyuan Duan Guojian Zhao Weisheng Zhao Fengxia Hu Qinghua Zhang Zhicheng Zhong Zhiqi Liu 《Nano Research》 SCIE EI CSCD 2024年第8期7250-7255,共6页
Searching for novel ferromagnetic oxides with high Curie temperature(TC)has been one of the main goals for oxide spintronics.The well-known perovskite cobaltate LaCoO_(3) is a classical ferromagnet in its thin-film fo... Searching for novel ferromagnetic oxides with high Curie temperature(TC)has been one of the main goals for oxide spintronics.The well-known perovskite cobaltate LaCoO_(3) is a classical ferromagnet in its thin-film form;however,it suffers from a low TC(~85 K).Here we report a new type of ferromagnetic La-Co-O films with an ultrahigh TC of~820 K.They are fabricated by pulsed laser deposition from a LaCoO_(3) target at low oxygen partial pressures.Detailed structural analysis indicates that they crystallize in terms of the Ruddlesden–Popper phase of La_(2)CoO_(4±x).In sharp contrast to the antiferromagnetism of bulk La_(2)CoO_(4),the strong ferromagnetism in the La_(2)CoO_(4±x) thin films is firmly demonstrated by magnetometry measurements,X-ray magnetic circular dichroism characterization,and magnetotransport experiments.More importantly,density functional theory calculations indicate that the nonstoichiometric oxygen induces an antiferromagnetic-to-ferromagnetic phase transition,accompanied by the orbital reconstruction of Co 3d electrons.Thus,our study provides an attractive strategy for designing or synthesizing exotic magnetic oxides with high ordering temperatures. 展开更多
关键词 ferromagnetic oxides ultra-high Curie temperature La_(2)CoO_(4) spin current transport oxygen engineering
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High speed laser cladding as a new approach to prepare ultra-high temperature ceramic coatings
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作者 Qiyao Deng Pengfei He +8 位作者 Chuan Sun Yang Li Yue Xing Yujie Wang Jinglong Li Xiubing Liang Xin Wang Yujie Zhou Yujun Cai 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2024年第2期143-154,共12页
Ultra-high temperature ceramic(UHTC)coatings are used to protect the hot-end components of hypervelocity aerocrafts from thermal ablation.This study provides a new approach to fabricate UHTC coatings with high speed l... Ultra-high temperature ceramic(UHTC)coatings are used to protect the hot-end components of hypervelocity aerocrafts from thermal ablation.This study provides a new approach to fabricate UHTC coatings with high speed laser cladding(HSLC)technology,and places more emphasis on investigating the formation mechanism,phase compositions,and mechanical properties of HSLC-UHTC coatings.Results show that a well-bonded interface between the coating and the tantalum alloy substrate can be formed.The coating is mainly composed of(Zr,Ta)C ceramic solid solution phase with a content of higher than 90% by volume and Ta(W)metal solid solution phase.At a relatively high powder feeding rate,the ZrC ceramic phase appears in the coating while a dense ZrC UHTC top layer with a thickness of up to~50μm is successfully fabricated.As for the mechanical properties of the HSLC coatings,the fracture toughness of the coating decreases with the increase of powder feeding rate.The increase of carbide solid solution phase can significantly improve the high temperature microhardness(552.7±1.8 HV0.5@1000℃).The innovative design of HSLC ZrC-based coatings on refractory alloys accomplishes continuous transitions on microstructure and properties from the substrate to the UHTC top layer,which is a very promising candidate scheme for thermal protection coating. 展开更多
关键词 high speed laser cladding(HSLC) ultra-high temperature ceramic(UHTC) thermal protection coating microstructure mechanical properties
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Microstructure and Oxidation Behavior of ZrB_(2)-SiC Ceramics Fabricated by Tape Casting and Reactive Melt Infiltration
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作者 TAN Min CHEN Xiaowu +5 位作者 YANG Jinshan ZHANG Xiangyu KAN Yanmei ZHOU Haijun XUE Yudong DONG Shaoming 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第8期955-964,共10页
ZrB_(2)-based ceramics typically necessitate high temperature and pressure for sintering,whereas ZrB_(2)-SiC ceramics can be fabricated at 1500℃using the process of reactive melt infiltration with Si.In comparison to... ZrB_(2)-based ceramics typically necessitate high temperature and pressure for sintering,whereas ZrB_(2)-SiC ceramics can be fabricated at 1500℃using the process of reactive melt infiltration with Si.In comparison to the conventional preparation method,reactive synthesis allows for the more facile production of ultra-high temperature ceramics with fine particle size and homogeneous composition.In this work,ZrSi_(2),B4C,and C were used as raw materials to prepare ZrB_(2)-SiC via combination of tape casting and reactive melt infiltration herein referred to as ZBC ceramics.Control sample of ZrB_(2)-SiC was also prepared using ZrB_(2) and SiC as raw materials through an identical process designated as ZS ceramics.Microscopic analysis of both ceramic groups revealed smaller and more uniformly distributed particles of the ZrB_(2) phase in ZBC ceramics compared to the larger particles in ZS ceramics.Both sets of ceramics underwent cyclic oxidation testing in the air at 1600℃for a cumulative duration of 5 cycles,each cycle lasting 2 h.Analysis of the oxidation behavior showed that both ZBC ceramics and ZS ceramics developed a glassy SiO_(2)-ZrO_(2) oxide layer on their surfaces during the oxidation.This layer severed as a barrier against oxygen.In ZBC ceramics,ZrO_(2) is finely distributed in SiO_(2),whereas in ZS ceramics,larger ZrO_(2) particles coexist with glassy SiO_(2).The surface oxide layer of ZBC ceramics maintains a dense structure because the well-dispersed ZrO_(2) increases the viscosity of glassy SiO_(2),preventing its crystallization during the cooling.Conversely,some SiO_(2) in the oxide layer of ZS ceramics may crystallize and form a eutectic with ZrO_(2),leading to the formation of ZrSiO_(4).This leads to cracking of the oxide layer due to differences in thermal expansion coefficients,weakening its barrier effect.An analysis of the oxidation resistance shows that ZBC ceramics exhibit less increase in oxide layer thickness and mass compared to ZS ceramics,suggesting superior oxidation resistance of ZBC ceramics. 展开更多
关键词 ultra-high temperature ceramic ZRB2-SIC oxidation behavior reactive melt infiltration
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Key Technologies in the Design and Construction of 300 m Ultra-High Arch Dams 被引量:14
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作者 RenkunWang 《Engineering》 SCIE EI 2016年第3期350-359,共10页
Starting with the Ertan arch dam (240 m high, 3300 MW) in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 (305 m), Xiaowan (294... Starting with the Ertan arch dam (240 m high, 3300 MW) in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 (305 m), Xiaowan (294.5m), and Xiluodu (285.5 m) arch dams have reached the 300 m height level (i.e., near or over 300 m), making them the tallest arch dams in the world. The design and construction of these 300 m ultra-high arch dams posed significant challenges, due to high water pressures, high seismic de- sign criteria, and complex geological conditions. The engineering team successfully tackled these chal- lenges and made critical breakthroughs, especially in the area of safety control. In this paper, the author summarizes various key technological aspects involved in the design and construction of 300 m ultra- high arch dams, including the strength and stability of foundation rock, excavation of the dam base and surface treatment, dam shape optimization, safety design guidelines, seismic analysis and design, treatment of a complex foundation, concrete temperature control, and crack prevention. The experience gained from these projects should be valuable for future practitioners. 展开更多
关键词 ultra-high arch dam Shape optimization Arch dam overall safety Seismic safety Concrete temperature contro
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Advances in ultra-high temperature ceramics,composites,and coatings 被引量:37
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作者 Dewei NI Yuan CHENG +10 位作者 Jiaping ZHANG Ji-Xuan LIU Ji ZOU Bowen CHEN Haoyang WU Hejun LI Shaoming DONG Jiecai HAN Xinghong ZHANG Qiangang FU Guo-Jun ZHANG 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第1期1-56,共56页
Ultra-high temperature ceramics(UHTCs)are generally referred to the carbides,nitrides,and borides of the transition metals,with the Group IVB compounds(Zr&Hf)and TaC as the main focus.The UHTCs are endowed with ul... Ultra-high temperature ceramics(UHTCs)are generally referred to the carbides,nitrides,and borides of the transition metals,with the Group IVB compounds(Zr&Hf)and TaC as the main focus.The UHTCs are endowed with ultra-high melting points,excellent mechanical properties,and ablation resistance at elevated temperatures.These unique combinations of properties make them promising materials for extremely environmental structural applications in rocket and hypersonic vehicles,particularly nozzles,leading edges,and engine components,etc.In addition to bulk UHTCs,UHTC coatings and fiber reinforced UHTC composites are extensively developed and applied to avoid the intrinsic brittleness and poor thermal shock resistance of bulk ceramics.Recently,high-entropy UHTCs are developed rapidly and attract a lot of attention as an emerging direction for ultra-high temperature materials.This review presents the state of the art of processing approaches,microstructure design and properties of UHTCs from bulk materials to composites and coatings,as well as the future directions. 展开更多
关键词 ultra-high temperature ceramics(UHTCs) COATINGS COMPOSITES high-entropy ultra-high temperature ceramics
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Design, Preparation and Properties of Carbon Fiber Reinforced Ultra-High Temperature Ceramic Composites for Aerospace Applications: A Review 被引量:62
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作者 Sufang Tang Chenglong Hu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第2期117-130,共14页
Carbon fiber reinforced ultra-high temperature ceramic (UHTC) composites, consisting of carbon fibers embedded in a UHTC-matrix or a C-SiC-UHTC-matrix, are deemed as the most viable class of materials that can overc... Carbon fiber reinforced ultra-high temperature ceramic (UHTC) composites, consisting of carbon fibers embedded in a UHTC-matrix or a C-SiC-UHTC-matrix, are deemed as the most viable class of materials that can overcome the poor fracture toughness and thermal shock resistance of monolithic UHTC ma- terials, and also improve the oxidation resistance and ablation resistance of C/C and C/SiC composites at ultra-high temperatures. In this review, we summarize the different processing routes of the compos- ites based on the UHTC introducing methods, including chemical vapor infiltration/deposition (CVI/D), precursor infiltration and pyrolysis (PIP), reactive melt infiltration (RMI), slurry infiltration (SI). in-sito reaction, hot pressing (HP), etc; and the advantages and drawbacks of each method are briefly dis- cussed. The carbon fiber reinforced UHTC composites can be highly tailorable materials in terms of fiber. interface, and matrix. From the perspective of service environmental applications for engine propul- sions anti hypersonic vehicles, the material designs (mainly focusing on the composition, quantity, structure of matrix, as well as the architecture of carbon fibers, UHTCs and pores), their relevant processing routes and properties (emphasizing on the mechanical and ablation properties) are discussed in this paper. In addition, we propose a material architecture to realize the multi-function through changing the distri- bution of carbon fibers, UHTCs and pores, which will be an important issue for future development of carbon fiber reinforced UHTC composites. 展开更多
关键词 Carbon fiber composites Ceramic matrix composites (CMC) ultra-high temperature ceramic (UHTC) Ablation
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Sol–gel derived porous ultra-high temperature ceramics 被引量:9
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作者 Fei LI Xiao HUANG +1 位作者 Ji-Xuan LIU Guo-Jun ZHANG 《Journal of Advanced Ceramics》 SCIE CSCD 2020年第1期1-16,共16页
Ultra-high temperature ceramics(UHTCs)are considered as a family of nonmetallic and inorganic materials that have melting point over 3000℃.Chemically,nearly all UHTCs are borides,carbides,and nitrides of early transi... Ultra-high temperature ceramics(UHTCs)are considered as a family of nonmetallic and inorganic materials that have melting point over 3000℃.Chemically,nearly all UHTCs are borides,carbides,and nitrides of early transition metals(e.g.,Zr,Hf,Nb,Ta).Within the last two decades,except for the great achievements in the densification,microstructure tailoring,and mechanical property improvements of UHTCs,many methods have been established for the preparation of porous UHTCs,aiming to develop high-temperature resistant,sintering resistant,and lightweight materials that will withstand temperatures as high as 2000℃for long periods of time.Amongst the synthesis methods for porous UHTCs,sol–gel methods enable the preparation of porous UHTCs with pore sizes from 1 to 500μm and porosity within the range of 60%–95%at relatively low temperature.In this article,we review the currently available sol–gel methods for the preparation of porous UHTCs.Templating,foaming,and solvent evaporation methods are described and compared in terms of processing–microstructure relations.The properties and high temperature resistance of sol–gel derived porous UHTCs are discussed.Finally,directions to future investigations on the processing and applications of porous UHTCs are proposed. 展开更多
关键词 sol–gel ultra-high temperature ceramics porous ceramics PROCESSING MICROSTRUCTURE
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Elucidating the role of preferential oxidation during ablation:Insights on the design and optimization of multicomponent ultra-high temperature ceramics 被引量:8
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作者 Ziming YE Yi ZENG +2 位作者 Xiang XIONG Qingbo WEN Huilin LUN 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第12期1956-1975,共20页
Multicomponent ultra-high temperature ceramics(UHTCs)are promising candidates for thermal protection materials(TPMs)used in aerospace field.However,finding out desirable compositions from an enormous number of possibl... Multicomponent ultra-high temperature ceramics(UHTCs)are promising candidates for thermal protection materials(TPMs)used in aerospace field.However,finding out desirable compositions from an enormous number of possible compositions remains challenging.Here,through elucidating the role of preferential oxidation in ablation behavior of multicomponent UHTCs via the thermodynamic analysis and experimental verification,the correlation between the composition and ablation performance of multicomponent UHTCs was revealed from the aspect of thermodynamics.We found that the metal components in UHTCs can be thermodynamically divided into preferentially oxidized component(denoted as MP),which builds up a skeleton in oxide layer,and laggingly oxidized component(denoted as ML),which fills the oxide skeleton.Meanwhile,a thermodynamically driven gradient in the concentration of MP and ML forms in the oxide layer.Based on these findings,a strategy for pre-evaluating the ablation performance of multicomponent UHTCs was developed,which provides a preliminary basis for the composition design of multicomponent UHTCs. 展开更多
关键词 multicomponent ceramics ultra-high temperature ceramics(UHTCs) preferential oxidation oxidation behavior ablation resistance
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Anisotropic thermal expansion in high-entropy multicomponent AlB_(2)-type diboride solid solutions
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作者 Frédéric Monteverde Mattia Gaboardi +3 位作者 Federico Saraga Lun Feng William Fahrenholtz Gregory Hilmas 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第1期331-343,共13页
High-entropy(HE)ultra-high temperature ceramics have the chance to pave the way for future applications propelling technology advantages in the fields of energy conversion and extreme environmental shielding.Among oth... High-entropy(HE)ultra-high temperature ceramics have the chance to pave the way for future applications propelling technology advantages in the fields of energy conversion and extreme environmental shielding.Among others,HE diborides stand out owing to their intrinsic anisotropic layered structure and ability to withstand ultra-high temperatures.Herein,we employed in-situ high-resolution synchrotron diffraction over a plethora of multicomponent compositions,with four to seven transition metals,with the intent of understanding the thermal lattice expansion following different composition or synthesis process.As a result,we were able to control the average thermal expansion(TE)from 1.3×10^(−6)to 6.9×10^(−6)K^(−1)depending on the combination of metals,with a variation of in-plane to out-of-plane TE ratio ranging from 1.5 to 2.8. 展开更多
关键词 ultra-high temperature ceramics borides high-entropy ceramics spark plasma sintering synchrotron diffraction anisotropic thermal expansion
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