scholarly journals Analysis of Long-Term Deterioration Characteristics of High Voltage Insulators

2019 ◽  
Vol 10 (1) ◽  
pp. 123 ◽  
Author(s):  
Taeyong Kim ◽  
Simpy Sanyal ◽  
Ja-Bin Koo ◽  
Ju-Am Son ◽  
In-Hyuk Choi ◽  
...  
Keyword(s):  
Zinc Coating ◽  
Three Dimensional ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Iron Corrosion ◽  
Long Duration ◽  
Porcelain Insulators ◽  
Corrosion Of Iron ◽  
Non Destructive

The deterioration of the cement that bonds the cap, pin, and porcelain shell of the porcelain insulators can be observed by three-dimensional computed tomography (3D-CT), a non-destructive test. When porcelain insulators are used for a long duration, the size of the pores existing in the cement increase as the cement expands due to the alkali-silica reaction (ASR). It is possible to visually confirm the corrosion of caps and pins. The degree of corrosion is divided into four noticeable stages (I–IV), and deterioration of cement includes one of the four stages of corrosion. The standard time of replacement of insulator vs. continued use is presented. As a result of X-ray diffraction (XRD) analysis, Fe is oxidized to Fe2O3 at 36, 43, 54, and 70 degrees. The corrosion in cement is caused by factors including the value of pH, oxygen content, and temperature. For the caps and pins, although a zinc coating is applied to prevent the corrosion of iron, corrosion of zinc is caused by substances present in the external environment. When the zinc coating begins to corrode, the corrosion of the Fe component of the cap and pin accelerates, causing mechanical/electrical problems.

scholarly journals The Effect of Simultaneous Si and Ti/Mo Alloying on High-Temperature Strength of Fe3Al-Based Iron Aluminides

Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4268
Author(s):  
Věra Vodičková ◽  
Martin Švec ◽  
Pavel Hanus ◽  
Pavel Novák ◽  
Antonín Záděra ◽  
...  
Keyword(s):  
Phase Composition ◽  
High Temperature ◽  
Yield Stress ◽  
Electron Backscatter Diffraction ◽  
Xrd Analysis ◽  
Iron Aluminides ◽  
High Temperature Strength ◽  
X Ray Diffraction ◽  
Backscatter Diffraction

The effect of phase composition and morphology on high-temperature strength in the compression of Fe-Al-Si-based iron aluminides manufactured by casting was investigated. The structure and high-temperature strength in the compression of three alloys—Fe28Al5Si, Fe28Al5Si2Mo, and Fe28Al5Si2Ti—were studied. Long-term (at 800 °C for 100 h) annealing was performed for the achievement of structural stability. The phase composition and grain size of alloys were primarily described by means of scanning electron microscopy equipped with energy dispersive analysis and Electron Backscatter Diffraction (EBSD). The phase composition was verified by X-ray diffraction (XRD) analysis. The effect of Mo and Ti addition as well as the effect of long-term annealing on high-temperature yield stress in compression were investigated. Both additives—Mo and Ti—affected the yield stress values positively. Long-term annealing of Fe28Al5Si-X iron aluminide alloyed with Mo and Ti deteriorates yield stress values slightly due to grain coarsening.

Self-Irradiation of Monazite Ceramics: Contrasting Behavior of PuPO4 and (La,Pu)PO4 Doped with Pu-238

2004 ◽  
Vol 824 ◽  
Author(s):  
Boris E. Burakov ◽  
Maria A. Yagovkina ◽  
Vladimir M. Garbuzov ◽  
Alexander A. Kitsay ◽  
Vladimir A. Zirlin
Keyword(s):  
Radiation Damage ◽  
Crack Formation ◽  
Alpha Decay ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Deep Blue ◽  
Long Term Storage ◽  
First Time ◽  
Term Storage

AbstractTo investigate the behavior of monazite during accelerated radiation damage, which simulates effects of long term storage, 238Pu-doped polycrystalline samples of (La,Pu)PO4 and PuPO4 were synthesized for the first time ever and studied using powder X-ray diffraction (XRD) analysis and optical microscopy. The starting precursor materials were obtained by precipitation of La and (or) Pu from their aqueous nitrate solutions followed by calcination in air at 700°C for 1 hour, cold pressing, and sintering in air at 1200-1250°C for 2 hours. The 238Pu contents in ceramic samples measured using gamma spectrometry were (in wt.% el.): 8.1 for (La,Pu)PO4 and 7.2 for PuPO4. The (La,Pu)PO4 monazite remained crystalline at ambient temperature up to a cumulative dose of 1.19 × 1025 alpha decays/m3. In contrast, the PuPO4 monazite became nearly completely amorphous at a relatively low dose of 4.2 × 1024 alpha decays/m3. Swelling and crack formation due to the alpha decay damage was observed in the PuPO4 ceramic. Also, under self-irradiation this sample completely changed color from initial deep blue to black. The (La,Pu)PO4 monazite was characterized by a similar change in color from initial light blue to gray, however, no swelling or crack formation have so far been observed. The results of this study allow us to conclude that the radiation damage behavior of monazite strictly depends on the chemical composition. The justification of monazite-based ceramics as actinide waste forms requires additional investigation.

Three-dimensional welding residual stresses evaluation based on the eigenstrain methodology via X-ray measurements at the surface

2014 ◽  
Vol 03 (04) ◽  
pp. 1450023
Author(s):  
Masaru Ogawa
Keyword(s):  
Neutron Diffraction ◽  
Residual Stresses ◽  
Three Dimensional ◽  
Strain Gauges ◽  
X Ray Diffraction ◽  
Stress Evaluation ◽  
X Ray ◽  
Residual Strains ◽  
Non Destructive ◽  
Evaluation Accuracy

In order to assure structural integrity for operating welded structures, it is necessary to evaluate crack growth rate and crack propagation direction for each observed crack non-destructively. Here, three dimensional (3D) welding residual stresses must be evaluated to predict crack propagation. Today, X-ray diffraction is used and the ultrasonic method has been proposed as non-destructive method to measure residual stresses. However, it is impossible to determine residual stress distributions in the thickness direction. Although residual stresses through a depth of several tens of millimeters can be evaluated non-destructively by neutron diffraction, it cannot be used as an on-site measurement technique. This is because neutron diffraction is only available in special irradiation facilities. Author pays attention to the bead flush method based on the eigenstrain methodology. In this method, 3D welding residual stresses are calculated by an elastic Finite Element Method (FEM) analysis from eigenstrains which are evaluated by an inverse analysis from released strains by strain gauges in the removal of the reinforcement of the weld. Here, the removal of the excess metal can be regarded as non-destructive treatment because toe of weld which may become crack starters can be eliminated. The effectiveness of the method has been proven for welded plates and pipes even with relatively lower bead height. In actual measurements, stress evaluation accuracy becomes poorer because measured values of strain gauges are affected by processing strains on the machined surface. In the previous studies, the author has developed the bead flush method that is free from the influence of the affecting strains by using residual strains on surface by X-ray diffraction. However, stress evaluation accuracy is not good enough because of relatively poor measurement accuracy of X-ray diffraction. In this study, a method to improve the estimation accuracy of residual stresses in this method is formulated, and it is shown numerically that inner welding residual stresses can be estimated accurately from the residual strains measured by X-ray diffraction.

Non-destructive identification of unknown minor phases in polycrystalline bulk alloys using three-dimensional X-ray diffraction

2017 ◽  
Vol 124 ◽  
pp. 206-214 ◽  
Author(s):  
Yiming Yang ◽  
Liang Xu ◽  
Yudan Wang ◽  
Guohao Du ◽  
Sam Yang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bulk Alloys ◽  
Non Destructive

X-Ray Diffraction Study of Cold Sprayed Ni-20Cr and Ni-50Cr Coatings on Boiler

2012 ◽  
Vol 620 ◽  
pp. 257-262 ◽  
Author(s):  
Niraj Bala ◽  
Harpreet Singh ◽  
Satya Prakash
Keyword(s):  
Chemical Composition ◽  
Xrd Analysis ◽  
Crystallographic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrd Study ◽  
Non Destructive ◽  
Sprayed Coatings ◽  
Boiler Steels ◽  
Better Than

X-ray diffraction (XRD) is a versatile, non-destructive technique that reveals detailed information about the chemical composition and crystallographic structure of materials. In this work Ni-20Cr and Ni-50Cr coatings were deposited on two boiler steels namely T22 and SA 516 steel. The measurement of residual stresses of these cold sprayed coatings was done with the help of X-ray diffraction technique. This paper discussed the XRD study of the as-sprayed coatings. Further the XRD technique was used to study the uncoated and coated steels after cyclic exposure to air, molten salt [Na2SO4-60%V2O5], and actual boiler environments. The results obtained from the XRD analysis have been shown. The weight change results showed that the coated steels performed better than their uncoated counterparts which might be attributed to the formation of protective phases.

Simulation and Evaluation of Residual Stress in Bone at the Interface with Implant

2011 ◽  
Vol 681 ◽  
pp. 315-320
Author(s):  
Abdelilah Benmarouane ◽  
Yeting Shi ◽  
Bastien Mireux ◽  
Thomas Buslaps ◽  
Alain Lodini
Keyword(s):  
X Ray Diffraction ◽  
Medical Field ◽  
Therapeutic Success ◽  
Element Analysis ◽  
Bone Implant ◽  
X Ray ◽  
Natural Bone ◽  
Simulation And Evaluation ◽  
Non Destructive

The use of the implants has become current since 1930. With the improvement of technology, titanium alloy coated with nano-hydroxyapatite has been used in the medical field. As a long-term establishment is a meter of the therapeutic success, it is necessary to use biocompatible implants in order to have good mechanical and fracture resistance at the interface bone-implant. In orthopaedic surgery Titanium (Ti-Al-4V) implants are currently coated with hydroxyapatite (HAp), Ca10 (PO4)6 (OH)2, in order to obtain a stable and functional direct connection between the bone and the implant. At the implant-bone interface the new bone reconstituted after implantation must have the same mechanicals properties as the natural bone in order to accept the implant. Therefore we studied the residuals stresses of the new bone crystals reconstituted at the interface applying non destructive x-ray diffraction and using finite element analysis in order to compare the results.

scholarly journals Differential taphonomic effects of petroleum seeps and karstic sinkholes on ancient dire wolf teeth: Hydrocarbon impregnation preserves fossils for chemical and histological analysis

2021 ◽  
Author(s):  
Sabrina B. Sholts ◽  
Leslea J. Hlusko ◽  
Joshua P. Carlson ◽  
Sebastian K. T. S. Wärmländer
Keyword(s):  
Histological Analysis ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Chemical Examination ◽  
Yield Information ◽  
Excellent Preservation ◽  
La Brea Tar Pits ◽  
Petroleum Seep ◽  
Dire Wolf

ABSTRACTHistological analysis of teeth can yield information on an organism’s growth and development, facilitating investigations of diet, health, environment, and long-term responses to selective pressures. In the Americas, an extraordinary abundance of Late Pleistocene fossils including teeth has been preserved in petroleum seeps, constituting a major source of information about biotic changes and adaptations at the end of the last glacial period. However, the usefulness of these fossils for histological studies is unclear, due to the unknown taphonomic effects of long-term deposition in petroleum. Here, we compare histological and chemical analyses on dire wolf (Canis dirus) teeth obtained from two different environments, i.e. a petroleum seep (Rancho La Brea tar pits, California) and a carstic sinkhole (Cutler Hammock sinkhole, Florida). Optical and scanning electron microscopy (SEM) together with X-ray diffraction (XRD) analysis revealed excellent preservation of dental microstructure in the seep sample, and the petroleum-induced discoloration was found not to interfere with the histological and chemical examination. By comparison, teeth from the sinkhole sample showed severe degradation and contamination of the dentine by exogenous substances. These results indicate that petroleum seep assemblages are useful, or even ideal, environments for preserving the integrity of fossil material for chemical and histological analysis.

Identification of α-phase crystallization Pigment Red 254 in artist's paints by powder x-ray diffraction

2014 ◽  
Vol 29 (3) ◽  
pp. 307-310
Author(s):  
Timothy Greening
Keyword(s):  
Xrd Analysis ◽  
Alpha Phase ◽  
Gas Chromatography Mass Spectrometry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Laser Raman ◽  
Α Phase ◽  
Non Destructive ◽  
Crystalline Component ◽  
Artistic Applications

Diketopyrrolopyrrole (DPP) is a pigment widely used in modern paints for industrial and artistic applications. Identification of this pigment in paint for art authentication and forensics has previously been accomplished with gas chromatography/mass spectrometry or Laser Raman. Three commercial artist's paints containing DPP were analyzed by x-ray diffraction (XRD). Alpha phase DPP was identified in two of the samples, barite extender the only crystalline component identified in the other sample. In conclusion, XRD analysis of paint samples can identify DPP, as can other organic analyses, but has the advantage of being non-destructive and also identifying the crystal structure. However, the fact that in one sample only extender could be identified does impose some limitations on the analysis of paints.

scholarly journals Processing of Orange Peel Biomass waste of Juice Industries and Valorization to Smart Acoustic Material

2021 ◽  
Author(s):  
Ganeswar Nath ◽  
Priyanka P Singh
Keyword(s):  
Particle Size ◽  
Fibrous Material ◽  
Orange Peel ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Biomass Waste ◽  
Reduction Property ◽  
Peripheral Mechanism ◽  
Class B ◽  
Non Destructive

Abstract Non-destructive technique like ultrasonication has played crucial role in fabrication of effective graded acoustic material using carbon rich organic waste material. The peculiar structural configuration inside the fibrous material like orange peel have attract the researcher to create special interest in designing of some building acoustic material as well as many technological products. The noise reduction property of orange peel fibres of different particle size has been improved considerably after ultrasonically mercerization of NaOH.High penetrating and dispersive property of ultrasonic wave to assemble and regrouping among the fibrous material are quite remarkable for enhancing noise attenuation inside the composite. Scanning Electron Microscopy (SEM), Energy Dispersive Spectra(EDS), Fourier Transform Infra-Red(FTIR) and X-Ray Diffraction(XRD) analysis of both untreated and treated orange peel fibre of different particle size indicate the deformation in cellulose as well as anti cellulose with the aid of ultrasonicationpermits the composites to be a suitable acoustic material. The result confirm that ultrasonic treated composite has potential to absorb 88.6% of sound which makes it a class- B noiseabsorber with peripheral mechanism within the composite.

Sign in / Sign up

Export Citation Format

Share Document