Thermochemical reduction of yttria-stabilized-zirconia crystals: Optical and electron microscopy

1998 ◽  
Vol 57 (21) ◽  
pp. 13439-13447 ◽  
Author(s):  
B. Savoini ◽  
C. Ballesteros ◽  
J. E. Muñoz Santiuste ◽  
R. González ◽  
Y. Chen
Keyword(s):  
Electron Microscopy ◽  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia ◽  
Optical And Electron Microscopy ◽  
Thermochemical Reduction

Effect of Coupled Conditions of Thermal Cycle and Dump Environment on Conductivity of 5mol% Yttria Stabilized Zirconia

2013 ◽  
Vol 591 ◽  
pp. 245-248 ◽  
Author(s):  
Jin Feng Xia ◽  
Hong Qiang Nian ◽  
Tao Feng ◽  
Hai Fang Xu ◽  
Dan Yu Jiang
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
High Temperature ◽  
Thermal Cycle ◽  
Oxygen Sensor ◽  
Yttria Stabilized Zirconia ◽  
Cyclic Change ◽  
Stabilized Zirconia ◽  
Transmission Electron

In some applications such as automotive oxygen sensor, 5mol% Y2O3stabilized zirconia (5YSZ) is generally used because it has both excellent ionic conductivity and mechanical properties. The automotive oxygen sensor would experience a cyclic change from high temperature (engine running) environment to the low temperature damp environment (in the tail pipe when vehicle stops). The conductivity change with coupled conditions of thermal cycle and dump environment in the 5mol%Y2O3ZrO2(5YSZ) system was examined by XRD,Impedance spectroscopy and transmission electron microscopy (SEM) in this paper.

Thermochemical reduction of Pr3+ -doped yttria-stabilized zirconia

1997 ◽  
Vol 72-74 ◽  
pp. 714-715 ◽  
Author(s):  
B. Savoini ◽  
J.E.Muñoz Santiuste ◽  
R. Gonźalez ◽  
Y. Chen
Keyword(s):  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia ◽  
Thermochemical Reduction

Effect of Coupled Conditions of Thermal Cycle and Dump Environment on Microstructure of 5mol% Yttria Stabilized Zirconia

2013 ◽  
Vol 544 ◽  
pp. 330-333 ◽  
Author(s):  
Jin Feng Xia ◽  
Ge Ming Liu ◽  
Niu Sheng Peng ◽  
Tao Feng ◽  
Hai Fang Xu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Raman Spectroscopy ◽  
Thermal Cycle ◽  
Oxygen Sensor ◽  
Yttria Stabilized Zirconia ◽  
Cyclic Change ◽  
Stabilized Zirconia ◽  
Scanning Electron

In some applications such as automotive oxygen sensor, 5mol% Y2O3stabilized zirconia (5YSZ) is generally used because it has both excellent ionic conductivity and mechanical properties. the automotive oxygen sensor would experience a cyclic change from high temperature (engine running) environment to the lowtemperature damp environment (in the tail pipe when vehicle stops). The microstructures change with coupled conditions of thermal cycle and dump environment in the 5mol%Y2O3–ZrO2 (5YSZ) system was examined by XRD，Raman spectroscopy and scanning electron microscopy (SEM) in this paper.

Analysis of the Y-TZP Ceramic Substucture in Blasting with Aluminum Oxide before and after Sintering

2014 ◽  
Vol 805 ◽  
pp. 576-580
Author(s):  
C.L. Melo-Silva ◽  
C.F. Carvalho ◽  
T.C.F. Melo-Silva ◽  
R.X. Freitas ◽  
F.R.F. Silva ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Aluminum Oxide ◽  
Good Alternative ◽  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia ◽  
Resin Cements ◽  
Before And After ◽  
Scanning Electron ◽  
Group 1

The objective of this study was to evaluate the microstructure of a ceramic based on yttria stabilized zirconia (Y-TZP) in blasting with aluminum oxide and its effect on the sintering. 25 pre-sintered Y-TZP blocks were obtained. Ten samples were blasted with alumina, and then all samples were sintered and divided into the groups: Control-no treatment; alumina G1-blasted with alumina and sintered; alumina and Rocatec G1-blasted, sintered, and Rocatec; alumina G2-sintered, alumina blasting; alumina and Rocatec G2-sintering, alumina blasting, and Rocatec. The samples were evaluated by a scanning electron microscopy. The qualitative analysis showed that the treated samples had an increase in the surface texture and that group 1– alumina and Rocatec– presented the silica incorporation to be regular and homogeneous. It was concluded that the treatment of pre-sintered surfaces is a good alternative in the bonding strength between the Y-TZP and the resin cements.

Degradation of Yttria Stabilized Zirconia Thermal Barrier Coatings by Molten CMAS (CaO-MgO-Al2O3-SiO2) Deposits

2008 ◽  
Vol 595-598 ◽  
pp. 207-212 ◽  
Author(s):  
Prabhakar Mohan ◽  
Biao Yuan ◽  
Travis Patterson ◽  
Vimal Desai ◽  
Yong Ho Sohn
Keyword(s):  
Electron Microscopy ◽  
Thermal Barrier Coatings ◽  
Yttria Stabilized Zirconia ◽  
Microstructural Development ◽  
Thermal Barrier ◽  
Isothermal Heat Treatment ◽  
Stabilized Zirconia ◽  
Free Standing ◽  
Barrier Coatings ◽  
Ysz Coating

In advanced gas turbine engines that operate in a dust-laden environment causing ingestion of siliceous debris into engines, thermal barrier coatings (TBCs) are highly susceptible to degradation by molten CMAS (calcium-magnesium alumino silicate) deposits. In this study, the degradation mechanisms other than the commonly reported thermomechanical damage are investigated with an emphasis on the thermochemical aspects of molten CMAS induced degradation of TBCs. Free-standing yttria stabilized zirconia (8YSZ) TBC specimens in contact with a model CMAS composition were subjected to isothermal heat treatment in air at temperatures ranging from 1200°C to 1350°C. Phase transformations and microstructural development were examined by using x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Starting at 1250°C, the molten CMAS readily infiltrated and dissolved the YSZ coating followed by reprecipitation of zirconia with a different morphology and composition that depends on the local melt chemistry. Significant amount of Y2O3 depleted monoclinic ZrO2 phase evolved from CMAS melt that dissolved ť-ZrO2 was evident. Thus the mechanism of dissolution and reprecipitation due to molten CMAS damage resulted in destabilization of the YSZ with disruptive phase transformation (t’ f + m).

Synthesis of Yttria-Stabilised Zirconia Matrices for Immobilisation of Actinides by Internal Gelation Method

2007 ◽  
Author(s):  
G. Benay ◽  
G. Modolo ◽  
R. Odoj
Keyword(s):  
Electron Microscopy ◽  
Spent Nuclear Fuel ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Internal Gelation ◽  
X Ray ◽  
Remote Handling ◽  
Co Conversion ◽  
Formation Of Cracks

In the scope of the co-conversion of actinides solutions obtained from partitioning spent nuclear fuel, the internal gelation of ceria-doped yttria-stabilized zirconia was investigated. This dust-free method to fabricate kernels, which can be used as fuel or pressed into pellets, is technically easy to implement and compatible with remote handling. The effects of the quantity of reactants used on the properties of the material were studied. Gels, kernels and pellets were analyzed by thermal analysis, electron microscopy and X-ray diffraction. It was found that the initial broth composition played an important role in the structure of kernels and the formation of cracks during thermal treatment. Pellets obtained with a repressing method were found to present densities up to 86% TD.

Solvothermal synthesis of zirconia and yttria-stabilized zirconia nanocrystalline particles

2007 ◽  
Vol 22 (1) ◽  
pp. 46-55 ◽  
Author(s):  
Xin M. Wang ◽  
Ping Xiao
Keyword(s):  
Electron Microscopy ◽  
Nitrogen Adsorption ◽  
Particle Size Analysis ◽  
Zirconium Hydroxide ◽  
Yttria Stabilized Zirconia ◽  
Size Analysis ◽  
Stabilized Zirconia ◽  
Particle Properties ◽  
Transmission Electron ◽  
Nanocrystalline Particles

A solvothermal method was used to prepare zirconia and yttria-stabilized zirconia (YSZ) particles using zirconium hydroxide and yttrium hydroxide particles as precursors and ethanol or isopropanol as reaction media. The particle properties were characterized with x-ray diffractometry, scanning electron microscopy, transmission electron microscopy, thermal analysis, laser particle-size analysis, nitrogen adsorption (Brunauer–Emmett–Teller method) and Zeta potential analysis. Cubic/tetragonal ZrO2 and YSZ nanocrystals with crystallite size around 5 nm were obtained. The effect of different hydroxide precursors, attrition milling of hydroxide precursors, solvothermal processing conditions, and mineralizer was investigated and discussed by referring to the crystallization process of zirconium hydroxides.

Sign in / Sign up

Export Citation Format

Share Document