Elastic Behaviour of Thin Stabilized-Zirconia Coatings

The residual stress in thin coatings of yttria stabilised-zirconia produced by Low Pressure Plasma Spraying were measured by X-ray Diffraction, using laboratory as well as synchrotron radiation sources. The specific microstructure, with absence of texture and fine distribution of nearly equiaxed grains, point out that despite the markedly anisotropic nature of cubic zirconia, coatings can be considered as macroscopically isotropic. This picture is also confirmed by the results of a parallel study, where the X-ray elastic constants were measured in-situ along two crystallographic directions ([440] and [620]): measured values agree fairly well with those calculated from single-crystal data under the Neerfeld-Hill assumptions. SR XRD provided a detailed information on the stress field across the thickness of the zirconia coatings. In particular the presence of a stress gradient was observed and modelled. The average stress is compressive, and increases with the coating thickness. Compression tend to increase from the surface toward the inside of the coating reaching a maximum of ~-1.0 GPa in a 24 µm coating.

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Characterization of Nanocrystalline Yttria-Stabilized Zirconia: An In Situ HTXRD Study

ISRN Nanotechnology ◽

10.5402/2011/305687 ◽

2011 ◽

Vol 2011 ◽

pp. 1-4 ◽

Cited By ~ 5

Author(s):

Mridula Biswas ◽

Chandrashekhar S. Kumbhar ◽

D. S. Gowtam

Keyword(s):

High Temperature ◽

Surface Area ◽

Coefficient Of Thermal Expansion ◽

High Specific Surface Area ◽

Yttria Stabilized Zirconia ◽

X Ray Diffraction ◽

Stabilized Zirconia ◽

X Ray ◽

Gel Combustion

Nanocrystalline yttria-stabilized zirconia powders, synthesized by the citrate nitrate gel combustion route, with yttria concentration varying from 8 to 12 mol% were studied by in situ high temperature X-ray diffraction in the temperature range of 25–1000°C. The sample obtained has a high specific surface area of 35 m2/g while calculated surface area was around 123 m2/g. The in situ high temperature X-ray diffraction study revealed that crystallite size remains in the range of 7–9 nm up to 800°C and then rapidly grows up to 21–23 nm upto 1000°C; only holding the material at 1000°C for 30 minutes can promote grain growth in the range of 42–49 nm. Coefficient of thermal expansion ranges from 9.65 to 9.03 ppm/°C for 8–12 mol% nanocrystalline yttria-stabilized zirconia.

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Pyrite micromorphology in three Australian Holocene sediments

Soil Research ◽

10.1071/sr98113 ◽

1999 ◽

Vol 37 (4) ◽

pp. 637 ◽

Cited By ~ 21

Author(s):

Richard T. Bush ◽

Leigh A. Sullivan

Keyword(s):

Electron Microscopy ◽

Sulfide Oxidation ◽

Estuarine Sediments ◽

X Ray Diffraction ◽

Thin Coatings ◽

X Ray ◽

Holocene Sediments ◽

Analytical Scanning Electron Microscopy ◽

Scanning Electron

The distribution and morphology of pyrite in 3 Holocene estuarine sediments were examined using light microscopy, analytical scanning electron microscopy, and X-ray diffraction. The distribution and morphologies of pyrite were similar with pyrite being dispersed throughout the soil matrices as well as concentrated in root remnants and other macropores. The pyrite occurred in both framboidal and irregularly shaped dense clusters from 4 to 15 µm diameter, and also in loose clusters. Individual crystals in these clusters ranged in size from 1 to 2 µm. Pyrite crystals exhibited octahedral, pyritohedral, and equant anhedral (i.e. rounded globular) habit. Organic matter coatings and clay coatings were common around pyrite at each site. Thin coatings of monosulfide with an acicular morphology occurred around some framboidal clusters at one site. The distribution of framboids and individual crystals in the clayey matrix, root remnants, and other macropores indicates that the pyrite in these sediments has formed in situ. These data have important implications for the rate of sulfide oxidation and acid production from these soils.

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Effect of non-hydrostatic conditions on the elastic behaviour of magnetite: an in situ single-crystal X-ray diffraction study

Physics and Chemistry of Minerals ◽

10.1007/s00269-007-0177-3 ◽

2007 ◽

Vol 34 (9) ◽

pp. 627-635 ◽

Cited By ~ 34

Author(s):

G. Diego Gatta ◽

I. Kantor ◽

T. Boffa Ballaran ◽

L. Dubrovinsky ◽

C. McCammon

Keyword(s):

Single Crystal ◽

Diffraction Study ◽

Elastic Behaviour ◽

X Ray Diffraction ◽

X Ray

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In-situ synchrotron X-ray diffraction analysis of the elastic behaviour of martensite and H-phase in a NiTiHf shape memory alloy fabricated by laser powder bed fusion

Additive Manufacturing Letters ◽

10.1016/j.addlet.2021.100003 ◽

2021 ◽

pp. 100003

Author(s):

Jiajia Shen ◽

Zhi Zeng ◽

Mohammadreza Nematollahi ◽

Norbert Schell ◽

Emad Maawad ◽

...

Keyword(s):

Shape Memory Alloy ◽

Diffraction Analysis ◽

Shape Memory ◽

Elastic Behaviour ◽

Powder Bed Fusion ◽

Laser Powder Bed Fusion ◽

X Ray Diffraction ◽

Powder Bed ◽

X Ray

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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In-situ investigation by X-ray diffraction and wafer curvature of phase formation and stress evolution during metal thin film – silicon reactions

Zeitschrift für Kristallographie Supplements ◽

10.1524/zksu.2007.2007.suppl_26.81 ◽

2007 ◽

Vol 2007 (suppl_26) ◽

pp. 81-89

Author(s):

O. Thomas

Keyword(s):

Thin Film ◽

Phase Formation ◽

Stress Evolution ◽

X Ray Diffraction ◽

X Ray ◽

Wafer Curvature ◽

Thin Film Silicon ◽

Metal Thin Film ◽

In Situ Investigation

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Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

Engineering and Technology Journal ◽

10.30684/etj.v38i4a.351 ◽

2020 ◽

Vol 38 (4A) ◽

pp. 491-500

Author(s):

Abeer F. Al-Attar ◽

Saad B. H. Farid ◽

Fadhil A. Hashim

Keyword(s):

Ionic Conductivity ◽

Electrochemical Impedance ◽

Structural Information ◽

Impedance Analysis ◽

High Energy ◽

Yttria Stabilized Zirconia ◽

X Ray Diffraction ◽

Stabilized Zirconia ◽

Powder Morphology ◽

X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

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