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 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 International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanical Properties and Performance of Engineering Ceramics and Composites VI Volume 32 Issue 2 written by Dileep Singh and published by John Wiley & Sons. This book was released on 2011-10-11 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a collection of papers from The American Ceramic Society's 35th International Conference on Advanced Ceramics and Composites, held in Daytona Beach, Florida, January 23-28, 2011. This issue includes papers presented in the Mechanical Behavior and Performance of Ceramics & Composites Symposium on topics such as processing-microstructure properties correlations; fracture mechanics, modeling and testing; tribological properties; applications; and processing.
Download or read book 21st Annual Conference on Composites Advanced Ceramics Materials and Structures A Volume 18 Issue 3 written by J. P. Singh and published by John Wiley & Sons. This book was released on 2009-09-28 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is part of the Ceramic Engineering and Science Proceeding (CESP) series. This series contains a collection of papers dealing with issues in both traditional ceramics (i.e., glass, whitewares, refractories, and porcelain enamel) and advanced ceramics. Topics covered in the area of advanced ceramic include bioceramics, nanomaterials, composites, solid oxide fuel cells, mechanical properties and structural design, advanced ceramic coatings, ceramic armor, porous ceramics, and more.
Download or read book Mechanical and Fractographic Characterization of Polymer derived Silicon Carbide Fibers written by Ernesto J. Serrano and published by . This book was released on 1998 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microstructural Characterisation of Silicon Carbide Fibres written by Kim Dyos and published by . This book was released on 1992 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 20th Annual Conference on Composites Advanced Ceramics Materials and Structures B Volume 17 Issue 4 written by John B. Wachtman and published by John Wiley & Sons. This book was released on 2009-09-28 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is part of the Ceramic Engineering and Science Proceeding (CESP) series. This series contains a collection of papers dealing with issues in both traditional ceramics (i.e., glass, whitewares, refractories, and porcelain enamel) and advanced ceramics. Topics covered in the area of advanced ceramic include bioceramics, nanomaterials, composites, solid oxide fuel cells, mechanical properties and structural design, advanced ceramic coatings, ceramic armor, porous ceramics, and more.
Download or read book Ceramic Fibers and Coatings written by Committee on Advanced Fibers for High-Temperature Ceramic Composites and published by National Academies Press. This book was released on 1998-05-05 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-temperature ceramic fibers are the key components of ceramic matrix composites (CMCs). Ceramic fiber properties (strength, temperature and creep resistance, for example)-along with the debonding characteristics of their coatings-determine the properties of CMCs. This report outlines the state of the art in high-temperature ceramic fibers and coatings, assesses fibers and coatings in terms of future needs, and recommends promising avenues of research. CMCs are also discussed in this report to provide a context for discussing high-temperature ceramic fibers and coatings.
Download or read book Composites Industry Abstracts written by and published by . This book was released on 1996 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ceramic Abstracts written by and published by . This book was released on 2000 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 20th Annual Conference on Composites Advanced Ceramics Materials and Structures written by and published by . This book was released on 1996 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Barrier Coatings written by Kang N. Lee and published by MDPI. This book was released on 2020-12-29 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: The global increase in air travel will require commercial vehicles to be more efficient than ever before. Advanced engine hot section materials are a key technology required to keep fuel consumption and emission to a minimum in next-generation gas turbines. Ceramic matrix composites (CMCs) are the most promising material to revolutionize gas turbine hot section materials technology because of their excellent high‐temperature properties. Rapid surface recession due to volatilization by water vapor is the Achilles heel of CMCs. Environmental barrier coatings (EBCs) is an enabling technology for CMCs, since it protects CMCs from water vapor. The first CMC component entered into service in 2016 in a commercial engine, and more CMC components are scheduled to follow within the next few years. One of the most difficult challenges to CMC components is EBC durability, because failure of EBC leads to a rapid reduction in CMC component life. Key contributors to EBC failure include recession, oxidation, degradation by calcium‐aluminum‐magnesium silicates (CMAS) deposits, thermal and thermo‐mechanical strains, particle erosion, and foreign object damage (FOD). Novel EBC chemistries, creative EBC designs, and robust processes are required to meet EBC durability challenges. Engine-relevant testing, characterization, and lifing methods need to be developed to improve EBC reliability. The aim of this Special Issue is to present recent advances in EBC technology to address these issues. In particular, topics of interest include but are not limited to the following: • Novel EBC chemistries and designs; • Processing including plasma spray, suspension plasma spray, solution precursor plasma spray, slurry process, PS-PVD, EB-PVD, and CVD; • Testing, characterization, and modeling; • Lifing.
Download or read book Ceramic Microstructures written by Antoni P. Tomsia and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 841 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume, titled Proceedings of the International Materials Symposium on Ce ramic Microstructures: Control at the Atomic Level summarizes the progress that has been achieved during the past decade in understanding and controlling microstructures in ceram ics. A particular emphasis of the symposium, and therefore of this volume, is advances in the characterization, understanding, and control of micro structures at the atomic or near-atomic level. This symposium is the fourth in a series of meetings, held every ten years, devoted to ceramic microstructures. The inaugural meeting took place in 1966, and focussed on the analysis, significance, and production of microstructure; the symposium emphasized the need for, and importance of characterization in achieving a more complete understanding of the physical and chemical characteristics of ceramics. A consensus emerged at that meeting on the critical importance of characterization in achieving a more complete understanding of ceramic properties. That point of view became widely accepted in the ensuing decade. The second meeting took place in 1976 at a time of world-wide energy shortages and thus emphasized energy-related applications of ceramics, and more specifically, microstructure-property relationships of those materials. The third meeting, held in 1986, was devoted to the role that interfaces played both during processing, and in influencing the ultimate properties of single and polyphase ceramics, and ceramic-metal systems.
Download or read book Cementitious Materials for Nuclear Waste Immobilization written by Rehab O. Abdel Rahman and published by John Wiley & Sons. This book was released on 2014-11-17 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cementitious materials are an essential part in any radioactive waste disposal facility. Conditioning processes such as cementation are used to convert waste into a stable solid form that is insoluble and will prevent dispersion to the surrounding environment. It is incredibly important to understand the long-term behavior of these materials. This book summarises approaches and current practices in use of cementitious materials for nuclear waste immobilisation. It gives a unique description of the most important aspects of cements as nuclear waste forms: starting with a description of wastes, analyzing the cementitious systems used for immobilization and describing the technologies used, and ending with analysis of cementitious waste forms and their long term behavior in an envisaged disposal environment. Extensive research has been devoted to study the feasibility of using cement or cement based materials in immobilizing and solidifying different radioactive wastes. However, these research results are scattered. This work provides the reader with both the science and technology of the immobilization process, and the cementitious materials used to immobilize nuclear waste. It summarizes current knowledge in the field, and highlights important areas that need more investigation. The chapters include: Introduction, Portland cement, Alternative cements, Cement characterization and testing, Radioactive waste cementation, Waste cementation technology, Cementitious wasteform durability and performance assessment.
Download or read book Conference Papers Index written by and published by . This book was released on 1987 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monthly. Papers presented at recent meeting held all over the world by scientific, technical, engineering and medical groups. Sources are meeting programs and abstract publications, as well as questionnaires. Arranged under 17 subject sections, 7 of direct interest to the life scientist. Full programs of meetings listed under sections. Entry gives citation number, paper title, name, mailing address, and any ordering number assigned. Quarterly and annual indexes to subjects, authors, and programs (not available in monthly issues).
Download or read book Spark Plasma Sintering of Materials written by Pasquale Cavaliere and published by Springer. This book was released on 2019-02-18 with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes spark plasma sintering (SPS) in depth. It addresses fundamentals and material-specific considerations, techniques, and applications across a broad spectrum of materials. The book highlights methods used to consolidate metallic or ceramic particles in very short times. It highlights the production of complex alloys and metal matrix composites with enhanced mechanical and wear properties. Emphasis is placed on the speed of the sintering processes, uniformity in product microstructure and properties, reduced grain growth, the compaction and sintering of materials in one processing step, various materials processing, and high energy efficiency. Current and potential applications in space science and aeronautics, automation, mechanical engineering, and biomedicine are addressed throughout the book.
