In situ generated ß-Yb₂Si₂O₇ environmental barrier coatings to protect non-oxide silicon-based ceramics in gas turbines (Band 16)
Title | In situ generated ß-Yb₂Si₂O₇ environmental barrier coatings to protect non-oxide silicon-based ceramics in gas turbines (Band 16) PDF eBook |
Author | Mateus Lenz Leite |
Publisher | Cuvillier Verlag |
Pages | 130 |
Release | 2022-02-25 |
Genre | Science |
ISBN | 3736965826 |
In face of an accelerating climate change, the reduction and substitution of fossil fuels is crucial to decarbonize energy production. Gas turbines can operate with versatile fuel sources like natural gas and future fuels such as hydrogen and ammonia. In a next future, thermal efficiencies above 65% are expected to be achieved by implementing non-oxide silicon-based (i.e. Si₃N₄, SiC and SiC/SiC) ceramic components. However, water vapor is one of the main combustion products, which leads to rapid corrosion due to the volatilization of the protective SiO₂ layer above 1200 °C. Hence, an in situ generated Yb₂Si₂O₇ double layered environmental barrier coating system composed of silazanes and the active fillers Yb2O3 and Si was processed at 1415 °C for 5 h in air to protect Si3N4, SiC and SiC/SiC from corrosion. The easy to apply coating system exhibits a dense microstructure with a thickness of up to 150 µm, besides an excellent adhesion strength (36.9 ± 6.2 MPa), hardness (6.9 ± 1.6 GPa) and scratch resistance (28 N). It remarkably overcomes over 15 thermal cycles between 1200 and 20 °C and shows almost no mass loss after harsh hot gas corrosion at 1200 °C for 200 h (pH2O = 0.15 atm, v = 100 m s⁻¹).
Environmental Barrier Coatings
Title | Environmental Barrier Coatings PDF eBook |
Author | Kang N. Lee |
Publisher | MDPI |
Pages | 168 |
Release | 2020-12-29 |
Genre | Science |
ISBN | 3039365177 |
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.
Reactive Sputter Deposition
Title | Reactive Sputter Deposition PDF eBook |
Author | Diederik Depla |
Publisher | Springer Science & Business Media |
Pages | 584 |
Release | 2008-06-24 |
Genre | Technology & Engineering |
ISBN | 3540766642 |
In this valuable work, all aspects of the reactive magnetron sputtering process, from the discharge up to the resulting thin film growth, are described in detail, allowing the reader to understand the complete process. Hence, this book gives necessary information for those who want to start with reactive magnetron sputtering, understand and investigate the technique, control their sputtering process and tune their existing process, obtaining the desired thin films.
Superalloys
Title | Superalloys PDF eBook |
Author | Matthew J. Donachie |
Publisher | ASM International |
Pages | 439 |
Release | 2002 |
Genre | Heat resistant alloys |
ISBN | 1615030646 |
This book covers virtually all technical aspects related to the selection, processing, use, and analysis of superalloys. The text of this new second edition has been completely revised and expanded with many new figures and tables added. In developing this new edition, the focus has been on providing comprehensive and practical coverage of superalloys technology. Some highlights include the most complete and up-to-date presentation available on alloy melting. Coverage of alloy selection provides many tips and guidelines that the reader can use in identifying an appropriate alloy for a specific application. The relation of properties and microstructure is covered in more detail than in previous books.
Advanced Ceramics and Composites
Title | Advanced Ceramics and Composites PDF eBook |
Author | Rainer Gadow |
Publisher | expert verlag |
Pages | 362 |
Release | 2000 |
Genre | Ceramic materials |
ISBN | 9783816918301 |
Nuclear Magnetic Resonance
Title | Nuclear Magnetic Resonance PDF eBook |
Author | Paul Hodgkinson |
Publisher | Royal Society of Chemistry |
Pages | 299 |
Release | 2021-11-11 |
Genre | Science |
ISBN | 1839164964 |
Nuclear magnetic resonance has proved a uniquely versatile and powerful spectroscopic technique, with applications across chemistry, physics and medicine. The success of NMR and its constant redevelopment means that the literature is vast and wide-ranging. Each chapter in this volume is a distillation of the key recent literature in different areas covering the spectrum of NMR theory and practice, and including solution-state, solid-state and in-vivo NMR. These reports will be invaluable both for new researchers wishing to engage with literature for the first time, and for seasoned practitioners, particularly service managers, wishing to keep in touch with the ever-expanding ways in which NMR is used.
Surface Coating and Modification of Metallic Biomaterials
Title | Surface Coating and Modification of Metallic Biomaterials PDF eBook |
Author | Cuie Wen |
Publisher | Woodhead Publishing |
Pages | 449 |
Release | 2015-03-31 |
Genre | Technology & Engineering |
ISBN | 1782423168 |
Despite advances in alternative materials, metals are still the biomaterial of choice for a number of clinical applications such as dental, orthopedic and cardiac implants. However, there are a number of intrinsic problems associated with implanting metal in the biological environment, such as wear, corrosion, biocompatibility and toxicity, which must be addressed. Modern technology has enabled scientists to modify metal surfaces or apply special coatings to metals to improve their performance safety. Surface Coating and Modification of Metallic Biomaterials will discuss the most important modification techniques and coatings for metals, first covering the fundamentals of metals as a biomaterial and then exploring surface modification techniques and coatings. - An expansive overview of surface modification techniques for biomedical use - In-depth exploration of issues arising from metal biomaterial use - Includes examples of applications in a clinical setting