Download or read book Electron Microscopy Characterisation of Polycrystalline Silicon Carbide written by Nolufefe Muriel Ndzane and published by . This book was released on 2014 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterisation of Polycrystalline Silicon Carbide by Scanning and Transmission Electron Microscopy written by Atomic Energy of Canada Limited and published by . This book was released on 1970 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Process related Defects in Silicon Carbide by Electron Microscopy written by Per O. Å Persson and published by . This book was released on 2001 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanical Chemical and Microstructural Characterization of Monazite Coated Silicon Carbide Fibers written by Narottam P. Bansal and published by . This book was released on 2000 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tensile strengths of as-received Hi-Nicalon and Sylramic fibers and those having monazite surface coatings, deposited by atmospheric pressure chemical vapor deposition, were measured at room temperature and the Weibull statistical parameters determined. The average tensile strengths of uncoated Hi-Nicalon and Sylramic fibers were 3.19 +/- 0.73 and 2.78 +/- 0.53 GPa with a Weibull modulus of 5.41 and 5.52, respectively. The monazite-coated Hi-Nicalon and Sylramic fibers showed strength loss of approx. 10 and 15 percent, respectively, compared with the as-received fibers. The elemental compositions of the fibers and the coatings were analyzed using scanning Auger microprobe and energy dispersive X-ray spectroscopy. The LaPO4 coating on Hi-Nicalon fibers was approximately stoichiometric and about 50 nm thick. The coating on the Sylramic fibers extended to a depth of about 100 to 150 nm. The coating may have been stoichiometric LaPO4 in the first 30 to 40 nm of the layer. However, the surface roughness of Sylramic fiber made this profile somewhat difficult to interpret. Microstructural analyses of the fibers and the coatings were done by scanning electron microscopy, transmission electron microscopy, and selected area electron diffraction.

Download or read book Electron Optical Studies of Heteroepitaxial Growth of Beta Silicon Carbide Layers Through Molten Metal Intermediates written by Joseph J. Comer and published by . This book was released on 1970 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beta silicon carbide has the potential of becoming an important semiconductor device material for hazardous military environments such as high temperature and radiation. This report is concerned with a study of the growth of thin single crystal films of beta silicon carbide through molten metal intermediates. Thin films of nickel, cobalt, chromium and iron were deposited by vacuum deposition on to the (0001) faces of single crystals of alpha silicon carbide. Then heteroepitaxial layers of beta silicon carbide were deposited through the molten metal films by the hydrogen reduction of methyltrichlorosilane. The deposited films were studied by electron microscopy, electron diffraction and electron beam microprobe analysis to determine the growth mechanism and to arrive at optimum conditions for heteroepitaxial growth. From the results obtained it was concluded that nickel and cobalt were equally effective in promoting epitaxial growth. Films of nickel only 20A in thickness were as effective as those up to 300A. Results with chromium and iron were disappointing for different reasons. Chromium did not etch the substrate surface uniformly because of poor wetting. With iron, whisker growth of beta silicon carbide occurred at the surface. Although in many respects the growth of mechanism resembled that of the vapor-liquid-solid method, certain differences were observed which make the actual growth mechanism using nickel and cobalt films still uncertain. (Author).

Download or read book Nondestructive Ultrasonic Characterization of Armor Grade Silicon Carbide written by Andrew Richard Portune and published by . This book was released on 2011 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ceramic materials have traditionally been chosen for armor applications for their superior mechanical properties and low densities. At high strain rates seen during ballistic events, the behavior of these materials relies upon the total volumetric flaw concentration more so than any single anomalous flaw. In this context flaws can be defined as any microstructural feature which detriments the performance of the material, potentially including secondary phases, pores, or unreacted sintering additives. Predicting the performance of armor grade ceramic materials depends on knowledge of the absolute and relative concentration and size distribution of bulk heterogeneities. Ultrasound was chosen as a nondestructive technique for characterizing the microstructure of dense silicon carbide ceramics. Acoustic waves interact elastically with grains and inclusions in large sample volumes, and were well suited to determine concentration and size distribution variations for solid inclusions. Methodology was developed for rapid acquisition and analysis of attenuation coefficient spectra. Measurements were conducted at individual points and over large sample areas using a novel technique entitled scanning acoustic spectroscopy. Loss spectra were split into absorption and scattering dominant frequency regimes to simplify analysis. The primary absorption mechanism in polycrystalline silicon carbide was identified as thermoelastic in nature. Correlations between microstructural conditions and parameters within the absorption equation were established through study of commercial and custom engineered SiC materials. Nonlinear least squares regression analysis was used to estimate the size distributions of boron carbide and carbon inclusions within commercial SiC materials. This technique was shown to additionally be capable of approximating grain size distributions in engineered SiC materials which did not contain solid inclusions. Comparisons to results from electron microscopy exhibited favorable agreement between predicted and observed distributions. Developed techniques were applied to large sample areas using scanning acoustic spectroscopy to map variations in the size distribution and concentration of grains and solid inclusions within the bulk microstructure. The experiments performed in this thesis form the foundation of a novel characterization technique capable of mapping variations in sample composition which could be extended to a wide range of dense polycrystalline heterogeneous materials.

Download or read book Mechanical Chemical and Microstructural Characterization of Monazite Coated Silicon Carbide Fibers written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tensile strengths of as-received Hi-Nicalon and Sylramic fibers and those having monazite surface coatings, deposited by atmospheric pressure chemical vapor deposition, were measured at room temperature and the Weibull statistical parameters determined. The average tensile strengths of uncoated Hi-Nicalon and Sylramic fibers were 3.19 +/- 0.73 and 2.78 +/- 0.53 GPa with a Weibull modulus of 5.41 and 5.52, respectively. The monazite-coated Hi-Nicalon and Sylramic fibers showed strength loss of approx. 10 and 15 percent, respectively, compared with the as-received fibers. The elemental compositions of the fibers and the coatings were analyzed using scanning Auger microprobe and energy dispersive X-ray spectroscopy. The LaPO4 coating on Hi-Nicalon fibers was approximately stoichiometric and about 50 nm thick. The coating on the Sylramic fibers extended to a depth of about 100 to 150 nm. The coating may have been stoichiometric LaPO4 in the first 30 to 40 nm of the layer. However, the surface roughness of Sylramic fiber made this profile somewhat difficult to interpret. Microstructural analyses of the fibers and the coatings were done by scanning electron microscopy, transmission electron microscopy, and selected area electron diffraction. Hi-Nicalon fiber consists of fine beta-SiC nanocrystals ranging in size from 1 to 30 mn embedded in an amorphous matrix. Sylramic is a polycrystalline stoichiometric silicon carbide fiber consisting of submicron beta-SiC crystallites ranging from 100 to 300 nm. Small amount of TiB2 nanocrystallites (approx. 50 nm) are also present. The LaPO4 coating on Hi-Nicalon fibers consisted of a chain of peanut shape particles having monazite-(La) structure. The coating on Sylramic fibers consisted of two layers. The inner layer was a chain of peanut shape particles having monazite-(La) structure. The outer layer was comprised of much smaller particles with a microcrystalline structure. Bansal, N. P. and Wheeler, D. R. and Chen, Y. L. Glenn Rese

Download or read book Processing and Microstructural Characterization of Reaction formed Silicon Carbide RFSC and Computer Simulations X ray Diffraction and High Resolution Transmission Electron Microscopy of Stacking Faults in Beta SiC written by Vijay Vasant Pujar and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book I Processing and Microstructural Characterization of Reaction formed Silicon Carbide RFSC and written by Vijay Vasant Pujar and published by . This book was released on 1997 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structural Characterization of Hard Materials by Transmission Electron Microscopy TEM written by Chun-sŏk Park and published by . This book was released on 2008 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microscopy of Semiconducting Materials 2007 written by A.G. Cullis and published by Springer Science & Business Media. This book was released on 2008-12-02 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains invited and contributed papers presented at the conference on ‘Microscopy of Semiconducting Materials’ held at the University of Cambridge on 2-5 April 2007. The event was organised under the auspices of the Electron Microscopy and Analysis Group of the Institute of Physics, the Royal Microscopical Society and the Materials Research Society. This international conference was the fifteenth in the series that focuses on the most recent world-wide advances in semiconductor studies carried out by all forms of microscopy and it attracted delegates from more than 20 countries. With the relentless evolution of advanced electronic devices into ever smaller nanoscale structures, the problem relating to the means by which device features can be visualised on this scale becomes more acute. This applies not only to the imaging of the general form of layers that may be present but also to the determination of composition and doping variations that are employed. In view of this scenario, the vital importance of transmission and scanning electron microscopy, together with X-ray and scanning probe approaches can immediately be seen. The conference featured developments in high resolution microscopy and nanoanalysis, including the exploitation of recently introduced aberration-corrected electron microscopes. All associated imaging and analytical techniques were demonstrated in studies including those of self-organised and quantum domain structures. Many analytical techniques based upon scanning probe microscopies were also much in evidence, together with more general applications of X-ray diffraction methods.

Download or read book Proceedings of The Twenty eighth Annual Meeting Houston Texas October 5 6 7 and 8 1970 written by Electron Microscopy Society of America and published by . This book was released on 1970 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Surface Characterization written by Dag Brune and published by John Wiley & Sons. This book was released on 2008-07-11 with total page 715 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Surface Characterization" provides an authoritative guide to the wide range of powerful techniques that are used to characterize the surfaces of materials. Practical in approach, it not only describes the major analytical techniques but emphasizes how they can be used to solve a multitude of chemical and physical problems. A special feature of the book is that the various techniques are grouped according to the material property under investigation. These parts are preceded by an overview comparing the capabilities of the characterization methods available. Extensive data tables allow the reader to assess rapidly the strengths as well as the pitfalls inherent in each method. Chapters on chemical composition, optical and crystallographic properties, microtopography, surface processes, tribological, electrical and magnetic properties of surface films are featured. In addition, chapters specializing on applications within the life sciences on the microscopic scale and chemometrics are included. "Surface Characterization" is addressed to both academic and industrial audiences. Scientists and engineers working on the production and development of new materials will find it an invaluable reference source. Physicist, chemists, chemical engineers, material scientists and engineers from every area of materials research will benefit from the wealth of practical advice the book provides.

Download or read book Amorphous Silicon Carbide Thin Films written by Mariana Amorim Fraga and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon carbide (SiC) has been described as a suitable semiconductor material to use in MEMS and electronic devices for harsh environments. In recent years, many developments in SiC technology as bulk growth, materials processing, electronic devices and sensors have been shown. Moreover, some studies show the synthesis, characterisation and processing of crystalline SiC films. However, few works have investigated the potential of amorphous silicon carbide (a-SiC) thin films for sensors applications. This book presents fundamentals of amorphous silicon carbide thin films and their applications in piezoresistive sensors for high temperature applications.

Download or read book SiC Natural and Synthetic Diamond and Related Materials written by A.A. Gippius and published by Elsevier. This book was released on 1992-04-24 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume addresses the burgeoning field of wide band gap materials. The 64 contributed and invited papers will do much to stimulate the well-justified ongoing work, both theoretical and experimental, in this area. The high standard of the papers attests to the significant progress that has been made in this field, as well as reporting on the challenging problems that still remain to be solved.

Download or read book Growth and Characterization of Silicon Carbide on AIN Si written by John H. Goldsmith and published by . This book was released on 2008 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Epitaxial silicon carbide (SiC) was grown using chemical vapor deposition (CVD) on silicon substrates with Aluminum Nitride (AIN) buffer layers. Subsequent films where characterized by Raman Spectroscopy, Scanning Electron microscopy, Atomic Force microscopy, and X-ray diffraction. There is a large lattice mismatch between SiC and silicon, by introducing an AIN buffer layer, which has a close lattice match to SiC, the strain on the film is reduced and hence the density of defects is reduced. Trimethylsilane, an relatively inert alternative to silane, was used as the precursor providing both the required silicon and carbon atoms.

Download or read book Energy Research Abstracts written by and published by . This book was released on 1990 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: