检索结果-南通市图书馆

Chinese Physics B 2022年第12期31卷 418-423页

作者： Xue Zhao Jin-Wu Jiang Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Zhejiang Laboratory Hangzhou 311100China

The yttria-stabilized zirconia(YSZ)is a famous thermal barrier coating material to protect hot-end components of an *** a characteristic feature of the YSZ,the surface roughness shall play an important role in the interface thermal conductance between the YSZ and gas,considering that the gas is typically at an extremely high *** investigate the effect of the surface roughness on the thermal conductance of the YSZ-gas interface with surface roughness described by nanoscale pores on the surface of the *** reveal two competitive mechanisms related to the microstructure of the pore,i.e.,the actual contact area effect and the confinement *** increase of the pore depth will enlarge the actual contact area between the YSZ and gas,leading to enhancement of the solid-gas interface thermal *** contrast to the positive actual contact area effect,the geometry-induced confinement effect greatly reduces the interface thermal *** findings shall offer some fundamental understandings for the microscopic mechanisms of the YSZ-gas interface thermal conductance.

关键词： interface thermal conductance thermal barrier coating solid-gas interface confinement effect

Effect of Supersonic Fine Particles Bombarding on the Service Life of thermal barrier coating

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2011年第5期24卷 911-916页

作者： LIN Xiaoping DONG Yun WANG Zhiping LIU Shiqiang REN Zhimin DING Kunying Department of Materials Science and Engineering Northeastern Universi（y at Qinhuangdao Qinhuangdao 066004 China College of Science Civil Aviation University of China Tianjin 300300 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China

thermally Grown Oxide（TGO） is a dominating component in controlling the effectiveness of thermal barrier *** the growth of TGO,whether we could homogeneously distribute Al atom on the TGO and the intermediate metal layer will be the key factor in forming TGO with continuous,uniform and single-ingredient（Al2O3）.In this experiment,we bombarded particles on to the metallic bound *** studied the influence of supersonic particle bombardment on the diffusion of *** hope to control the growth of TGO by monitoring the diffusion of *** barrier coating（TBC）,which consists of a NiCoCrAlY bond coat and a ZrO2-8Y2O3（wt.%） topcoat（TC）,is fabricated on the nickel-base superalloy by air plasma spray（APS）.NiCoCrAlY bond coat is treated by supersonic fine particles bombarding（SFPB）.The morphology,oxidation behavior of TBC and phase are characterized by scanning electron microscope（SEM） equipped with an energy dispersive spectromrter（EDS） and X-ray diffractometer（XRD）.The influence of supersonic fine particles bombarding technique on the service life of thermal barrier coating is *** results show that SFPB technique improves the flaw of excessive surface undulation in the as-sprayed bond coat.A continuous,uniform and single-ingredient（Al2O3） TGO can quickly form in the SFPB TBC during high temperature oxidation *** thickening of TGO is relatively *** will effectively suppress the formation of other non-protective ***,SFPB technique reduces the growth stress level generated by the continuous growth of TGO,and also avoids the stress concentration induced by formation of the large particle spinal *** barrier coating still remains well after 350 thermal *** service life of TBC is *** proposed research provides theoretical basis and technical references to further improve and enhance the SFPB technique.

关键词： thermal barrier coating stress concentration supersonic fine particles bombarding thermally grown oxide

Comparative Study on Different Methods for Prediction of thermal Insulation Performance of thermal barrier coating Used on Turbine Blades

在线全文

学校读者我要写书评

暂无评论

Journal of thermal Science 2024年第1期33卷 172-189页

作者： ZHANG Zhixin ZENG Wu ZHANG Xiaodong ZENG Yuntao Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As turbine inlet temperature gets higher and higher,thermal barrier coating(TBC) is more and more widely used in turbine *** turbine blades with TBC,it is of great significance to evaluate the temperature distribution of its substrate metal quickly and accurately,especially during the design *** different degrees of simplification such as whether to consider the change of the geometric size of the fluid domain by TBC and whether to consider the planar heat conduction in TBC,three different methods used in conjugate heat transfer(CHT) simulation to model the TBC of the turbine blades have been developed and widely used by ***,little research has been conducted to investigate the influence of the three methods on the temperature distribution of turbine *** fill this gap,three geometric models were *** are a solid conduction model with a substrate metal layer and a TBC layer,a transonic turbine vane with internal cooling and TBC,and a plate cylindrical film hole cooling model with *** methods were used in these geometric models and their differences were carefully analyzed and *** result shows that for the conduction model used in this paper,with the same TBC surface temperature distribution,the difference between the three methods is very small and can be *** a transonic turbine vane with internal cooling,regarding the local maximum temperature of the substrate-TBC interface,the largest difference between the method in which TBC is considered as a thermal resistance or a virtual layer of cells and the method in which three-dimensional heat conduction equation of TBC is solved occurs at the trailing *** difference near the leading edge is below *** employed to the film cooling model,the difference of the laterally averaged temperature of the substrate-TBC interface can be 8 K which is mainly due to the change of the length to diameter ratio of the film cooling hole by *** the substrate

关键词： turbine blade thermal barrier coating conjugate heat transfer film cooling hole

Simulation of residual stresses and their effects on thermal barrier coating systems using finite element method

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2015年第3期58卷 49-58页

作者： ZHU JianGuo CHEN Wei XIE HuiMin Faculty of Civil Engineering and Mechanics Jiangsu University School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Key Laboratory of Applied Mechanics (AML) Department of Engineering Mechanics Tsinghua University

thermal barrier coating(TBC)systems are widely used in industrial gas-turbine ***,premature failures have impaired the use of TBCs and cut down their lifetime,which requires a better understanding of their failure *** the present study,experimental studies of isothermal cycling are firstly carried out with the observation and estimation of *** to the experimental results,a finite element model is established for the analysis of stress perpendicular to the TBC/BC *** residual stress distributions in TBC are obtained to reflect the influence of mechanical properties,oxidation,and interfacial *** calculated results show that the maximum tensile stress concentration appears at the peak of TBC and continues to increase with thermal *** of the microstructural characteristics of plasma-sprayed TBCs,cracks initialize in tensile stress concentration(TSC)regions at the peaks of TBC and propagate along the TBC/BC interface resulting in the spallation of ***,the inclusion of creep is crucial to failure prediction and is more important than the inclusion of sintering in the simulation.

关键词： residual stress failure mechanism finite element method thermal barrier coating

Influence of Annealing on the Grain Growth and thermal Diffusivity of Nanostructured YSZ thermal barrier coating

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2006年第6期22卷 793-797页

作者： Na WANG Chungen ZHOU Shengkai GONG Huibin XU Department of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The nanostructured zirconia coatings were deposited by atmospherically plasma spraying. Scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and X-ray diffraction were used to investigate the microstructure of the zirconia coatings. thermal diffusivity values at normal temperatures have been evaluated by laser flash technique. Effect of annealing on the microstructure evolution of the zirconia coating has been performed. The grains and thermal diffusivity are increased with increasing annealing time and temperature. The grain growth is according to the GRIGC （the grain rotation induced grain coalescence） mechanism. The increase in thermal diffusivity is attributed to the grain growth and the decrease in porosity of nanostructured zirconia coatings.

关键词： Grain size thermal diffusivity thermal barrier coating Plasma spraying

Improved Toughness and thermal Expansion of Non-stoichiometry Gd_(2-x)Zr_(2+x)O_(7+x/2) Ceramics for thermal barrier coating Application

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2016年第1期32卷 28-33页

作者： Lei Guo Mingzhu Li Yu Zhang Fuxing Ye School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Advanced Joining Technology Tianjin UniversityTianjin 300072China Key Lab of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300072China

Gd2Zr207 has been considered as a promising thermal barrier coating candidate, but its toughness and thermal expansion coefficient （TEC） need to be improved. In this study, Gd2-xZr2 ＋xO7 ＋χ/2 （χ = 0, 0.1, 0.3, 0.5, 0.7） compounds were produced to improve the toughness and enlarge the TEC. Gd2Zr207 and Gd1.9Zr2.1O7.05 exhibited pyrochlore structure, while Gd2-xZr2 ＋xO7 ＋χ/2 （χ = 0.3, 0.5, 0.7） consisted of pyrochlore and t＇-ZrO2 phases. With increasing ZrO2 content, the pyrochlore in the compounds had decreased lattice parameter, and its ordering degree decreased when χ 〈 0.3, then it almost kept unchanged with higher ZrO2 content. Among the Gd2-xZr2 ＋xO7 ＋χ/2 ceramics investigated, the toughness of the compounds in- creased with increasing ZrO2 content, while Gd1.7Zr23O7.15 exhibited the largest TEC. The related mechanisms were discussed in detail.

关键词： thermal barrier coating Ceramic Phase structure Toughness thermal expansion coefficient

Investigation on plasma-sprayed ZrO_2 thermal barrier coating on nickel alloy substrate

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University of Technology 2002年第4期9卷 225-228页

作者：卢安贤常鹰蔡小梅 School of Materials Science and Engineering Central South University

The thermal barrier coatings with NiCrAlY alloy bonding layer, NiCrAlY Y 2O 3 stabilized ZrO 2 transition layer and Y 2O 3 stabilized ZrO 2 ceramic layer are prepared on nickel alloy substrates using the plasma spray technique. The relationship among the composition, structure and property of the coatings are investiga ted by means of optical microscope, scanning electronic microscope and the experiments of thermal shock resistance cycling and high temperature oxidation resistance. The results show that the structure design of introdu cing a transition layer between Ni alloy substrate and ZrO 2 ceramic coating guarantees the high quality and properties of the coatings; ZrO 2 coatings doped with a little SiO 2 possesses better thermal shock resistance and more excellent hot corrosion resistance as compared with ZrO 2 coating materials without SiO 2 ;the improvement in performance of ZrO 2 coating doped with SiO 2 is due to forming more dense coating structure by self closing effects of the flaws and pores in the ZrO 2 coatings.

关键词： plasma spray Ni alloy substrate transition layer ZrO2 ceramic layer thermal barrier coating

Fracture of thermal barrier coating with multiple surface cracks and delaminations:Interlayer effect

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2014年第7期21卷 2579-2583页

作者：范学领许荣 M.Kikuchi State Key Laboratory for Strength and Vibration of Mechanical Structures(School of Aerospace Engineering Xi'an Jiaotong University) Department of Mechanical Engineering Faculty of Science and TechnologyTokyo University of Science

Multiple surface cracks and interfacial delamination are the major failure mechanisms in film/substrate *** effect of interlayer upon the failure mechanisms of interfacial delamination concomitant to surface crack was *** element model was developed to obtain the stress and energy release rate(ERR),which governs the propagation of interface *** dependences of delamination upon the geometry and constitutive properties of interlayer were *** results indicate that the effect of elastic modulus of interlayer on the steady state ERR is *** cases of different geometrical parameters,however,the steady ERR decreases with the increase of the interlayer *** findings lead to the conclusion that the interlayer constraint has significant effect on the ERR and thus coating life,which can be adopted to modify the ceramic top coat.

关键词： thermal barrier coating delamination interlayer energy release rate

Microstructural features and properties of plasma sprayed YPSZ/NiCrAlY thermal barrier coating (TBC)

在线全文

学校读者我要写书评

暂无评论

China Welding 2004年第2期13卷 91-96页

作者：孙大谦王文权宣兆志宫文彪 Key Laboratory of Automobile Materials Jilin University Changchun 130025

The plasma sprayed thermal barrier coating (TBC) consists of NiCrAlY bond coating and yttria partially stabilized zirconia (YPSZ) top coating. NiCrAlY coating mainly contains Ni solid solution with face centered cubic lattice, Al_2O_3 oxides and pores. The most obvious feature of YPSZ coating with tetragonal zirconia is a lot of vertical microcracks in this coating. The thermal insulation capability of the TBC increased with an increase in YPSZ coating thickness, the temperature drop across the TBC increasing from 60℃ to 92℃ with increasing YPSZ coating thickness from 100 μm to 500 μm. The thermal shock resistance of the TBC decreased with increasing YPSZ coating thickness and cracks initiated mainly in original vertical microcrack tips of the YPSZ coating and propagated not only along YPSZ coating/ NiCrAlY coating interface but also through NiCrAlY coating. The oxidation process of the TBC at 1 200℃ can be divided into two stages: transient oxidation stage with rapid oxidation rate and steady oxidation stage with slow oxidation. Their transition time was about 10 hours. The weight gain for 100 hours was 3.222 mg/mm2. It is favorable to increase YPSZ coating toughness and to decrease the pores and oxides of the TBC system for improving thermal shock resistance and oxidation resistance of the TBC.

关键词： plasma spray thermal barrier coating microstructure properties

Effect of Al-deposition on erosion resistance of plasma sprayed thermal barrier coating

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2015年第8期25卷 2587-2593页

作者：张小锋周克崧董淑娟徐伟宋进兵刘敏 .华南理工大学材料科学与工程学院广州510640 广州有色金属研究院新材料研究所广州510650 IRTES-LERMPS Laboratory Université de Technologie de Belfort-Montbéliard

A columnar Al film was firstly deposited on the top of 7%Y2O3？stabilized zirconia （7YSZ） ceramic coating in thermal barrier coating （TBC） system by magnetron sputtering. A vacuum treatment was then carried out at 700 °C for 1 h and 900 °C for 5 h to improve the erosion resistance of Al-deposited TBC. Aα-Al2O3 layer was in situ synthesized on the top of 7YSZ coating via vacuum heat treatment. The microstructure evolution of Al-deposited TBC illustrated that a loose surface-layer and a dense sub-layer formed on the top of 7YSZ coating after vacuum treatment. The phase structures of the as-sprayed TBC and the Al-deposited TBC after vacuum heat treatment were characterized by X-ray diffraction （XRD） and transmission electron microscope （TEM） assisted with focused ion beam （FIB）. Particulate erosion resistances of the as-sprayed TBC and treated TBC were compared at room temperature. In addition, erosion mechanism and schematic diagram were proposed. The results show that the Al-deposited TBC after vacuum heat treatment has better particulate erosion resistance than the as-sprayed one.

关键词： thermal barrier coating erosion resistance in situ synthesis