Effectiveness of Diffusion Barrier Coatings for Mo-Re Embedded in C/SiC and C/C
Author:
Publisher:
Published: 2001
Total Pages: 48
ISBN-13:
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Effectiveness of Diffusion Barrier Coatings for Mo-Re Embedded in C/Sic and C/C
Author: National Aeronautics and Space Adm Nasa
Publisher: Independently Published
Published: 2018-09-19
Total Pages: 48
ISBN-13: 9781723829871
DOWNLOAD EBOOKAdvanced high-temperature cooling applications may often require the elevated-temperature capability of carbon/silicon carbide or carbon/carbon composites in combination with the hermetic capability of metallic tubes. In this paper, the effects of C/SiC and C/C on tubes fabricated from several different refractory metals were evaluated. Though Mo, Nb, and Re were evaluated in the present study, the primary effort was directed toward two alloys of Mo-Re, namely, arc cast Mo-41Re and powder metallurgy Mo-47.5Re. Samples of these refractory metals were subjected to either the PyC/SiC deposition or embedding in C/C. MoSi2(Ge), R512E, and TiB2 coatings were included on several of the samples as potential diffusion barriers. The effects of the processing and thermal exposure on the samples were evaluated by conducting burst tests, microhardness surveys, and scanning electron microscopic examination (using either secondary electron or back scattered electron imaging and energy dispersive spectroscopy). The results showed that a layer of brittle Mo-carbide formed on the substrates of both the uncoated Mo-41Re and the uncoated Mo-47.5Re, subsequent to the C/C or the PyC/SiC processing. Both the R512E and the MoSi2(Ge) coatings were effective in preventing not only the diffusion of C into the Mo-Re substrate, but also the formation of the Mo-carbides. However, none of the coatings were effective at preventing both C and Si diffusion without some degradation of the substrate.Glass, David E. and Shenoy, Ravi N. and Wang, Zeng-Mei and Halbig, Michael C.Glenn Research Center; Langley Research CenterPROTECTIVE COATINGS; CARBON-CARBON COMPOSITES; RHENIUM; FABRICATION; REFRACTORY METALS; POWDER METALLURGY; SILICON CARBIDES; MOLYBDENUM CARBIDES; DIFFUSION; HERMETIC SEALS; DEGRADATION; SUBSTRATES; TITANIUM BORIDES; BURST TESTS; SCANNING ELECTRON MICROSCOPY; HIGH TEMPERATURE; MICROHARDNESS
Environmental Barrier Coatings
Author: Kang N. Lee
Publisher: MDPI
Published: 2020-12-29
Total Pages: 168
ISBN-13: 3039365177
DOWNLOAD EBOOKThe 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.
Handbook of Advanced Ceramics and Composites
Author: Yashwant Mahajan
Publisher: Springer
Published: 2020-11-26
Total Pages: 1527
ISBN-13: 9783030163464
DOWNLOAD EBOOKThis handbook presents an authoritative account of the potential of advanced ceramics and composites in strategic applications, including defense, national security, aerospace, and energy security (especially nuclear energy). It highlights how their unique combination of superior properties such as low density, high strength, high elastic modulus, high hardness, high temperature capability, and excellent chemical and environmental stability are optimized in technologies within these fields. The handbook is organized according to application type. It allows readers to learn about strategies that have been used in different fields and to transfer them to their own. The book addresses a wide variety of ceramics and their composites, including PZT ceramics, carbon nanotubes, aerogels, silica radomes, relaxor ferroelectrics, and many others.
Plasma Electrolytic Oxidation (PEO) Coatings
Author: Marta Mohedano
Publisher: MDPI
Published: 2021-06-02
Total Pages: 172
ISBN-13: 3036505520
DOWNLOAD EBOOKPlasma electrolytic oxidation (PEO), also known as micro-arc oxidation (MAO), functionalizes surfaces, improving the mechanical, thermal, and corrosion performance of metallic substrates, along with other tailored properties (e.g., biocompatibility, catalysis, antibacterial response, self-lubrication, etc.). The extensive field of applications of this technique ranges from structural components, in particular, in the transport sector, to more advanced fields, such as bioengineering. The present Special Issue covers the latest advances in PEO‐coated light alloys for structural (Al, Mg) and biomedical applications (Ti, Mg), with 10 research papers and 1 review from leading research groups around the world.
Advances in Ceramic Matrix Composites
Author: I M Low
Publisher: Woodhead Publishing
Published: 2018-01-20
Total Pages: 844
ISBN-13: 0081021674
DOWNLOAD EBOOKAdvances in Ceramic Matrix Composites, Second Edition, delivers an innovative approach to ceramic matrix composites, focusing on the latest advances and materials developments. As advanced ceramics and composite materials are increasingly utilized as components in batteries, fuel cells, sensors, high-temperature electronics, membranes and high-end biomedical devices, and in seals, valves, implants, and high-temperature and wear components, this book explores the substantial progress in new applications. Users will gain knowledge of the latest advances in CMCs, with an update on the role of ceramics in the fabrication of Solid Oxide Fuel Cells for energy generation, and on natural fiber-reinforced eco-friendly geopolymer and cement composites. The specialized information contained in this book will be highly valuable to researchers and graduate students in ceramic science, engineering and ceramic composites technology, and engineers and scientists in the aerospace, energy, building and construction, biomedical and automotive industries. - Provides detailed coverage of parts and processing, properties and applications - Includes new developments in the field, such as natural fiber-reinforced composites and the use of CMCs in Solid Oxide Fuel Cells (SOFCs) - Presents state-of-the-art research, enabling the reader to understand the latest applications for CMCs
Handbook of Ceramic Composites
Author: Narottam P. Bansal
Publisher: Springer Science & Business Media
Published: 2006-08-25
Total Pages: 547
ISBN-13: 0387239863
DOWNLOAD EBOOKThis valuable handbook has been compiled by internationally renowned researchers in the field. Each chapter is focused on a specific composite system or a class of composites, presenting a detailed description of processing, properties, and applications.
Advances in Composites Manufacturing and Process Design
Author: Philippe Boisse
Publisher: Woodhead Publishing
Published: 2015-07-29
Total Pages: 493
ISBN-13: 1782423206
DOWNLOAD EBOOKThe manufacturing processes of composite materials are numerous and often complex. Continuous research into the subject area has made it hugely relevant with new advances enriching our understanding and helping us overcome design and manufacturing challenges. Advances in Composites Manufacturing and Process Design provides comprehensive coverage of all processing techniques in the field with a strong emphasis on recent advances, modeling and simulation of the design process. Part One reviews the advances in composite manufacturing processes and includes detailed coverage of braiding, knitting, weaving, fibre placement, draping, machining and drilling, and 3D composite processes. There are also highly informative chapters on thermoplastic and ceramic composite manufacturing processes, and repairing composites. The mechanical behaviour of reinforcements and the numerical simulation of composite manufacturing processes are examined in Part Two. Chapters examine the properties and behaviour of textile reinforcements and resins. The final chapters of the book investigate finite element analysis of composite forming, numerical simulation of flow processes, pultrusion processes and modeling of chemical vapour infiltration processes. - Outlines the advances in the different methods of composite manufacturing processes - Provides extensive information on the thermo-mechanical behavior of reinforcements and composite prepregs - Reviews numerical simulations of forming and flow processes, as well as pultrusion processes and modeling chemical vapor infiltration
Ceramic Coatings
Author: Feng Shi
Publisher: BoD – Books on Demand
Published: 2012-02-24
Total Pages: 300
ISBN-13: 9535100831
DOWNLOAD EBOOKThe main target of this book is to state the latest advancement in ceramic coatings technology in various industrial fields. The book includes topics related to the applications of ceramic coating covers in enginnering, including fabrication route (electrophoretic deposition and physical deposition) and applications in turbine parts, internal combustion engine, pigment, foundry, etc.
Applied Coal Petrology
Author: Isabel Suárez-Ruiz
Publisher: Academic Press
Published: 2008
Total Pages: 388
ISBN-13: 9780080450513
DOWNLOAD EBOOKAn understanding of basic coal properties is important for achieving reductions in trace element emissions and improving the efficiency of combustion and combined-cycle gasification. The production of methane from coal beds is related to the properties of the in situ coal. Similarly, coal bed sequestration of carbon dioxide produced from combustion is dependent on the reservoir properties. Environmental problems accompany coal on its way from the mine to the point of utilization and beyond. Health aspects related with coal mining and coal utilization are also included because, in planning for coal use, it is impossible to separate environmental and health issues from the discussion of coal utilization. The book is aimed at a wide audience, ranging from researchers, lecturers and students to professionals in industry and discusses issues (such as the environmental, and health) that are of concern to the general public as a whole.-
