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Microstructure and thermal cycling behavior of nanostructured yttria partially stabilized zirconia (YSZ) thermal barrier coatings

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Journal of Rare Earths 2010年第S1期28卷 198-201页

作者：孙杰张丽丽赵丹 School of Environmental and Chemical Engineering Shenyang Ligong University

Nanostructured yttria partially stabilized zirconia(YSZ) coatings were prepared by atmospheric plasma spraying(APS) using the conglomeration made by zirconia nanoparticle as the raw *** measurement methods,which consisted of scanning electron microscopy(SEM),transmission electron microscopy(TEM) and thermal cycling behavior,were used to character the morphology,composition and thermal oxidation behavior of the powder and the *** the results,it was shown that the YSZ coating was the laminar structure,and the elements distribution in the bond and top coat were *** YSZ coatings were composed of fine grains with size ranging from 30 to 110 *** laminar layers with columnar grains were surrounded with unmelted parts of the nanostructured powder and some equiaxed *** the as-sprayed nanostructured zirconia coatings,there existed pores that were less than 1 μ*** cracks were observed on some of the crystal *** cyclic oxidation experiment showed that the nanostructured coating had longer thermal cycling lifetime to exhibit the promising thermal cyclic oxidation *** failure of the nanostructured TBC was similar to the failure of conventional APS TBC.

关键词： nanostructure yttria stabilized zirconia isothermal oxidation thermal barrier coatings rare earths

Effects of the Nozzle Design on the Properties of Plasma Jet and Formation of YSZ Coatings under Low Pressure Conditions

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 954-961页

作者： SUN Chengqi GAO Yang YANG Deming FU Yingqing College of Material Science and Engineering Dalian Maritime University Key Laboratory of Ship-Machinery Maintenance & Manufacture Dalian Maritime University

How to control the quality of the coatings has become a major problem during the plasma spraying. Because nozzle contour has a great influence on the characteristic of the plasma jet, two kinds of plasma torches equipped with a standard cylindrical nozzle and a converging-diverging nozzle are designed for low pressure plasma spraying（LPPS） and very low pressure plasma spraying（VLPPS）. yttria stabilized zirconia（YSZ） coatings are obtained in the reducing pressure environment. The properties of the plasma jet without or with powder injection are analyzed by optical emission spectroscopy, and the electron temperature is calculated based on the ratio of the relative intensity of two Arlspectral lines. The results show that some of the YSZ powder can be vaporized in the low pressure enlarged plasma jet, and the long anode nozzle may improve the characteristics of the plasma jet. The coatings deposited by LPPS are mainly composed of the equiaxed grains and while the unmelted powder particles and large scalar pores appear in the coatings made by VLPPS. The long anode nozzle could improve the melting of the powders and deposition efficiency, and enhance the coatings＇ hardness. At the same time, the long anode nozzle could lead to a decrease in the overspray phenomenon. Through the comparison of the two different size＇s nozzle, the long anode is much more suitable for making the YSZ coatings.

关键词： plasma torch yttria stabilized zirconia electron temperature equiaxed grain thermal barrier coatings

Effect of High Resistance Phases on Metal—Insulator Transition of La0.67Ca0.33MnO3

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Chinese Physics Letters 2003年第7期20卷 1116-1119页

作者：夏正才袁松柳张力江张国宏冯文唐洁刘莉刘胜唐超群 DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074

The temperature dependence of resistivity ρ of YSZ doping composite of (1-x)La0.67Ca0.33MnO3 + xYSZ and Y2O3 doping composite of (1-y)La0.67Ca0.33MnO3 + yY2O3 is investigated, respectively, in a temperature range 77-300 K, where the YSZ represents yttria-stabilized zirconia (8 mol%Y2O3+92 mol% ZrO2). Experimental results show that the YSZ doping level has important effects on both the metal-insulator (M-I) transition temperatures and zero field resistivity of the composites of (1-x)La0.67Ca0.33MnO3 + xYSZ. However, the Y2O3 doping level has little effect on the M-I transition temperatures and the zero field resistivity of (1-y)La0.67Ca0.33MnO3 + yY2O3 only increases slightly. The difference between the two types of composites may mainly result from the different distribution of high resistance phases at the grain boundaries and/or surfaces of La0.67Ca0.33MnO3 grains rather than the substitution of La3+ ions with Y3+ ions.

关键词： Composites Metal-insulator transition high resistance yttria stabilized zirconia Electrical resistivity temperature dependence Transition Temperature doping level Types of composites Phase

Theoretical Aspects on Doped-zirconia for Solid Oxide Fuel Cells:from Structure to Conductivity

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Chinese Journal of Chemical Physics 2021年第2期34卷 125-136,I0001页

作者： Shu-hui Guan Zhi-pan Liu Shanghai Academy of Agricultural Sciences Shanghai 201403China Collaborative Innovation Center of Chemistry for Energy Material Shanghai Key Laboratory of molecular Catalysis and Innovative MaterialsKey Laboratory of Computational Physical ScienceDepartment of ChemistryFudan UniversityShanghai 200438China

Solid oxide fuel cells(SOFCs)are regarded to be a key clean energy system to convert chemical energy(e.g.H_(2) and O_(2))into electrical energy with high efficiency,low carbon footprint,and fuel *** electrolyte,typically doped zirconia,is the"state of the heart"of the fuel cell technologies,determining the performance and the operating temperature of the overall *** stabilized zirconia(YSZ)have been widely used in SOFC due to its excellent oxide ion conductivity at high *** composition and temperature dependence of the conductivity has been hotly studied in experiment and,more recently,by theoretical *** characterization of the atomic structure for the mixed oxide system with different compositions is the key for elucidating the conductivity behavior,which,however,is of great challenge to both experiment and *** review presents recent theoretical progress on the structure and conductivity of YSZ *** compare different theoretical methods and their results,outlining the merits and deficiencies of the *** highlight the recent results achieved by using stochastic surface walking global optimization with global neural network potential(SSW-NN)method,which appear to agree with available experimental *** advent of machine-learning atomic simulation provides an affordable,efficient and accurate way to understand the complex material phenomena as encountered in solid *** future research directions for design better electrolytes are also discussed.

关键词： Solid oxide fuel cells yttria stabilized zirconia Conductivity Atomistic structure Theoretical aspects

Thermal properties of glass-ceramic bonded thermal barrier coating system

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Transactions of Nonferrous Metals Society of China 2015年第2期25卷 457-464页

作者： S.GHOSH Bio-ceramics and Coating Division CSIR–Central Glass and Ceramic Research Institute

The thermal properties of a thermal barrier coating （TBC） system comprised of BaO-MgO-SiO_2 based glass-ceramic bond coating, 8% （mass fraction） yttria stabilized zirconia （8YSZ） top coating and nimonic alloy substrate were evaluated. The thermal diffusivity and thermal conductivity of the TBC coated substrate were lower than those of bare substrate and glass-ceramic coated substrate under identical conditions. The specific heat capacity, thermal diffusivity and thermal conductivity of the TBC coated substrate increase with the increase of the temperature. Further, it is observed that the thermal conductivity of the TBC system decreases with the increase in the top coating thickness.

关键词： vglass-ceramic coating thermal barrier coating thermal properties yttria stabilized zirconia

Low Cost Fabrication and Performance of YSZ Electrolyte Thin-Substrate

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Low Cost Fabrication and Performance of YSZ Electrolyte Thin...