scholarly journals Synchrotron X-ray measurement techniques for thermal barrier coated cylindrical samples under thermal gradients

2013 ◽  
Vol 84 (8) ◽  
pp. 083904 ◽  
Author(s):  
Sanna F. Siddiqui ◽  
Kevin Knipe ◽  
Albert Manero ◽  
Carla Meid ◽  
Janine Wischek ◽  
...  
Keyword(s):  
Measurement Techniques ◽  
Thermal Barrier ◽  
Thermal Gradients ◽  
X Ray ◽  
Cylindrical Samples

scholarly journals Towards a methodology for the characterisation of the fabric of wet clays using X-ray scattering

2019 ◽  
Vol 92 ◽  
pp. 01005
Author(s):  
Georgios Birmpilis ◽  
Reza Ahmadi-Naghadeh ◽  
Jelke Dijkstra
Keyword(s):  
Materials Science ◽  
Measurement Techniques ◽  
Invasive Technique ◽  
Colloidal Systems ◽  
Characteristic Distance ◽  
X Ray ◽  
Hydrophobic Coating ◽  
X Ray Scattering ◽  
Wide Range ◽  
Ray Scattering

X-ray scattering is a promising non-invasive technique to study evolving nano- and micromechanics in clays. This study discusses the experimental considerations and a successful method to enable X-ray scattering to study clay samples at two extreme stages of consolidation. It is shown that the proposed sample environment comprising flat capillaries with a hydrophobic coating can be used for a wide range of voids ratios ranging from a clay suspension to consolidated clay samples, that are cut from larger specimens of reconstituted or natural clay. The initial X-ray scattering results using a laboratory instrument indicate that valuable information on, in principal evolving, clay fabric can be measured. Features such as characteristic distance between structural units and particle orientations are obtained for a slurry and a consolidated sample of kaolinite. Combined with other promising measurement techniques from Materials Science the proposed method will help advance the contemporary understanding on the behaviour of dense colloidal systems of clay, as it does not require detrimental sample preparation

X-RAY PHOTOELECTRON SPECTROSCOPY STUDIES ON THE BONDING PROPERTIES OF AMORPHOUS CARBON NITRIDE FILMS SYNTHESIZED BY PULSED LASER DEPOSITION WITH DIFFERENT SUBSTRATE TEMPERATURES

2005 ◽  
Vol 12 (02) ◽  
pp. 185-195
Author(s):  
M. RUSOP ◽  
T. SOGA ◽  
T. JIMBO
Keyword(s):  
Pulsed Laser Deposition ◽  
Amorphous Carbon ◽  
Photoelectron Spectroscopy ◽  
Carbon Nitride ◽  
Measurement Techniques ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
X Ray ◽  
Amorphous Carbon Nitride ◽  
Substrate Temperatures

Amorphous carbon nitride films ( a-CN x) were deposited by pulsed laser deposition of camphoric carbon target with different substrate temperatures (ST). The influence of ST on the synthesis of a-CN x films was investigated. The nitrogen-to-carbon (N/C) and oxygen-to-carbon (O/C) atomic ratios, bonding state, and microstructure of the deposited a-CN x films were characterized by X-ray photoelectron spectroscopy and were confirmed by other standard measurement techniques. The bonding states between C and N , and C and O in the deposited films were found to be significantly influenced by ST during the deposition process. The N/C and O/C atomic ratios of the a-CN x films reached the maximum value at 400°C. ST of 400°C was proposed to promote the desired sp 3-hybridized C and the C 3 N 4 phase. The C–N bonding of C–N , C=N and C≡N were observed in the films.

Preparation of Ultra–Fine La3NbO7 Powder by Solid State Reaction

2012 ◽  
Vol 512-515 ◽  
pp. 158-161 ◽  
Author(s):  
Ling Dai ◽  
Qiang Xu ◽  
Shi Zhen Zhu ◽  
Ling Liu
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Single Phase ◽  
Thermal Barrier ◽  
X Ray Diffraction ◽  
X Ray ◽  
Granular Particle ◽  
Fine Particle Size ◽  
Ultra Fine Particle ◽  
Different Temperatures

As a new candidate material for the ceramic layer in thermal barrier coatings (TBCs) system, La3NbO7 was synthesized with La2O3 powder and Nb2O5 powder by solid state reaction. The stating powders with a mole ratio of La to Nb of 3:1 were mixed and then the mixture was calcined under the different temperatures(800°C, 1000°C, 1200°C) and dwell times(2h, 6h, 10h). The phase structure of the powder was observed by X–ray diffraction(XRD), and the microstructure of the sample was observed by scanning electron microscope(SEM). The effect of calcination temperature and dwell Time on the phase formation were examined. The results indicate that the La3NbO7 powder with single phase can be synthesized successfully at 1200°C for 10h in air, and the La3NbOsub>7 powders synthesized have an ultra-fine particle size of 0.5˜1µm with a granular particle shape. With the temperature increasing, LaNbO4/sub> was synthesized firstly and then La3NbO7 was synthesized with a mole ratio of La2O3 to LaNbO4 of 1:1.

scholarly journals Diffracting-grain identification from electron backscatter diffraction maps during residual stress measurements: a comparison between the sin2ψ and cosα methods

2019 ◽  
Vol 52 (4) ◽  
pp. 828-843 ◽  
Author(s):  
Dorian Delbergue ◽  
Damien Texier ◽  
Martin Lévesque ◽  
Philippe Bocher
Keyword(s):  
Residual Stress ◽  
Grain Size ◽  
Tilt Angle ◽  
Measurement Errors ◽  
Electron Backscatter Diffraction ◽  
Measurement Techniques ◽  
Single Exposure ◽  
X Ray ◽  
Electron Backscatter ◽  
Backscatter Diffraction

X-ray diffraction (XRD) is a widely used technique to evaluate residual stresses in crystalline materials. Several XRD measurement methods are available. (i) The sin2ψ method, a multiple-exposure technique, uses linear detectors to capture intercepts of the Debye–Scherrer rings, losing the major portion of the diffracting signal. (ii) The cosα method, thanks to the development of compact 2D detectors allowing the entire Debye–Scherrer ring to be captured in a single exposure, is an alternative method for residual stress measurement. The present article compares the two calculation methods in a new manner, by looking at the possible measurement errors related to each method. To this end, sets of grains in diffraction condition were first identified from electron backscatter diffraction (EBSD) mapping of Inconel 718 samples for each XRD calculation method and its associated detector, as each method provides different sets owing to the detector geometry or to the method specificities (such as tilt-angle number or Debye–Scherrer ring division). The X-ray elastic constant (XEC) ½S 2, calculated from EBSD maps for the {311} lattice planes, was determined and compared for the different sets of diffracting grains. It was observed that the 2D detector captures 1.5 times more grains in a single exposure (one tilt angle) than the linear detectors for nine tilt angles. Different XEC mean values were found for the sets of grains from the two XRD techniques/detectors. Grain-size effects were simulated, as well as detector oscillations to overcome them. A bimodal grain-size distribution effect and `artificial' textures introduced by XRD measurement techniques are also discussed.

scholarly journals Microstructure and Corrosion Behavior of Friction Stir-Welded 6061 Al/AZ31 Mg Joints with a Zr Interlayer

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1115 ◽  
Author(s):  
Yang Zheng ◽  
Xiaomeng Pan ◽  
Yinglei Ma ◽  
Shuming Liu ◽  
Libin Zang ◽  
...  
Keyword(s):  
Corrosion Behavior ◽  
Galvanic Corrosion ◽  
Stir Zone ◽  
Thermal Barrier ◽  
Al Alloy ◽  
X Ray ◽  
Friction Stir ◽  
Base Materials ◽  
Dissimilar Alloys ◽  
Scanning Electron

Friction stir welding (FSW) with a Zr interlayer was employed to join dissimilar alloys of 6061 Al and AZ31 Mg. The microstructures of Al/Mg and Al/Zr/Mg joints were investigated by optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometer (EDS). The results showed that the central part of the Zr interlayer was smashed and intermixed with the base materials in the stir zone, whereas the undamaged part remained stable at the Al/Mg interface. The formation of Al–Mg intermetallic compounds (IMCs) was suppressed by the Zr interlayer due to its synergetic effects of chemical modification and thermal barrier. The electrochemical measurements revealed a differentiated corrosion behavior for each joint, where the corrosion rate of representative regions increased in the order of Al alloy < Mg alloy < heat-affected zone < stir zone. The immersion tests indicated an enhancement in corrosion resistance for the Al/Zr/Mg joint compared with the Al/Mg joint, which is owing to the mitigated galvanic corrosion between the base materials by the Zr interlayer.

X-Ray Imaging of the Filling of “T” Shaped Microchannel Using a MEDIPIX2 Pixel Detector

2004 ◽  
Author(s):  
A. Vabre ◽  
E. Manach ◽  
O. Gal ◽  
S. Legoupil
Keyword(s):  
Measurement Technique ◽  
Chemical Engineering ◽  
Measurement Techniques ◽  
Photon Counting ◽  
Pixel Detector ◽  
Lab On Chip ◽  
X Ray ◽  
Space Resolution ◽  
Research Perspectives ◽  
European Collaboration

Fluid flows in “T” or “Y” shaped structures of microchannels are studied in order to develop modeling approaches as well as adapted measurement techniques. The applications of these structures are numerous and concern in particular biology and chemical engineering for which the integration of microchannels in lab-on-chip and/or microreactor is an important challenge. Our works concern the development of a measurement technique for the study of the filling of a “T” shaped microchannel structure by a liquid. In the studied channels, the experimental constraints are strong. Indeed, the space steps involved within the phenomena are very much reduced and vary from 1 to 10 μm. Moreover, the dynamics of the flow implies a high acquisition frequency, ranging from 10 to 100 Hz. Our technological choice is based on the measurement of the attenuation of an X-ray beam in the matter. The main advantage of this non-intrusive technique is that it can be implemented even in media opaque to visible light. Also, that X-ray techniques can theoretically reach a better space resolution than optical ones. The measurement technique is quantitative and a 3D measurement is achievable by tomography. These methods are validated for problems located at centimetric space steps and high acquisition frequencies, [1], [2]. The objective of this work is to match the microfluidics field requirement (space steps and attenuation contrast), while preserving high time frequencies. Our experimental bench consists of a X-ray generator, that makes possible to obtain high enlargements of the observed object whit a reduced blur in the image. The image is obtained by a pixel detector called Medipix2. This detector is under development within a European collaboration which gathers 16 partners around the CERN, the CEA being a partner. The main assets of this detector are its high space resolution, its operational photon counting mode and its high acquisition frequency. The presented works constitute a very first implementation and validation of the proposed technique for the microfluidics field. Experimental results are obtained and presented. They allow a measurement of the filling conditions of the “T” shape structure of microchannels. The orientations and research perspectives to improve the obtained results by the technique could be evaluated accurately and important basis of our work are now established and quantified for the future.

Sign in / Sign up

Export Citation Format

Share Document