Download or read book In situ generated Yb Si O environmental barrier coatings to protect non oxide silicon based ceramics in gas turbines Band 16 written by Mateus Lenz Leite and published by Cuvillier Verlag. This book was released on 2022-02-25 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).

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 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 Novel Environmental Barrier Coatings for Resistance Against Degradation by Molten Glassy Deposits in the Presence of Water Vapor written by Caitlin Maureen Toohey and published by . This book was released on 2011 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Environmental barrier coatings (EBCs) are used to prevent oxidation of underlying ceramic-matrix composite (CMC) structural components in aircraft gas-turbine engines. As operating temperatures increase, ingested airborne sand poses a serious threat to the stability of these coatings, because the sand adheres to the hot EBC surfaces and melts, forming calcium--magnesium--aluminosilicate (CMAS) glass. The reaction of EBCs with molten CMAS can lead to EBC delamination. Additionally, the interaction of water vapor with the CMAS--reacted EBCs can result in the formation of undesirable phases. Yb2Si2O-- has been identified as a promising EBC ceramic, based on its desirable properties: phase stability up to 1600°C, low thermal expansion coefficient mismatch with common CMCs, and potential resistance against degradation by CMAS and water vapor. As--sintered Yb2Si2O-- and CMAS--coated Yb2Si2O-- are tested in an air environment and in a water vapor environment, at a temperature of 1300°C in both cases. The behavior of these ceramics is compared to that of reference materials. Results from oxidation and chemical stability studies and analyses are presented.

Download or read book Ceramic Materials and Components for Engines written by Jürgen G. Heinrich and published by John Wiley & Sons. This book was released on 2008-11-21 with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several ceramic parts have already proven their suitability for serial application in automobile engines in very impressive ways, especially in Japan, the USA and in Germany. However, there is still a lack of economical quality assurance concepts. Recently, a new generation of ceramic components, for the use in energy, transportation and environment systems, has been developed. The efforts are more and more system oriented in this field. The only possibility to manage this complex issue in the future will be interdisciplinary cooperation. Chemists, physicists, material scientists, process engineers, mechanical engineers and engine manufacturers will have to cooperate in a more intensive way than ever before. The R&D activities are still concentrating on gas turbines and reciprocating engines, but also on brakes, bearings, fuel cells, batteries, filters, membranes, sensors and actuators as well as on shaping and cutting tools for low expense machining of ceramic components. This book summarizes the scientific papers of the 7th International Symposium "Ceramic Materials and Components for Engines". Some of the most fascinating new applications of ceramic meterials in energy, transportation and environment systems are presented. The proceedings shall lead to new ideas for interdisciplinary activities in the future.

Download or read book Semiconductor Gas Sensors written by Raivo Jaaniso and published by Woodhead Publishing. This book was released on 2019-09-24 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor Gas Sensors, Second Edition, summarizes recent research on basic principles, new materials and emerging technologies in this essential field. Chapters cover the foundation of the underlying principles and sensing mechanisms of gas sensors, include expanded content on gas sensing characteristics, such as response, sensitivity and cross-sensitivity, present an overview of the nanomaterials utilized for gas sensing, and review the latest applications for semiconductor gas sensors, including environmental monitoring, indoor monitoring, medical applications, CMOS integration and chemical warfare agents. This second edition has been completely updated, thus ensuring it reflects current literature and the latest materials systems and applications. Includes an overview of key applications, with new chapters on indoor monitoring and medical applications Reviews developments in gas sensors and sensing methods, including an expanded section on gas sensor theory Discusses the use of nanomaterials in gas sensing, with new chapters on single-layer graphene sensors, graphene oxide sensors, printed sensors, and much more

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 Electrostatic Levitator written by and published by . This book was released on 1999 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Porous Ceramic Materials written by Dean Mo Liu and published by Trans Tech Publications Ltd. This book was released on 1995-09-26 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of porous ceramic materials has presented a new challenge to various industries, because porous ceramics are more durable in severe environments and their surface characteristics permit them to satisfy very specific requirements.

Download or read book Extractive Metallurgy of Niobium written by A.K. Suri and published by Routledge. This book was released on 2017-11-13 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: The growth and development witnessed today in modern science, engineering, and technology owes a heavy debt to the rare, refractory, and reactive metals group, of which niobium is a member. Extractive Metallurgy of Niobium presents a vivid account of the metal through its comprehensive discussions of properties and applications, resources and resource processing, chemical processing and compound preparation, metal extraction, and refining and consolidation. Typical flow sheets adopted in some leading niobium-producing countries for the beneficiation of various niobium sources are presented, and various chemical processes for producing pure forms of niobium intermediates such as chloride, fluoride, and oxide are discussed. The book also explains how to liberate the metal from its intermediates and describes the physico-chemical principles involved. It is an excellent reference for chemical metallurgists, hydrometallurgists, extraction and process metallurgists, and minerals processors. It is also valuable to a wide variety of scientists, engineers, technologists, and students interested in the topic.

Download or read book Introduction to Glass Science and Technology written by James E Shelby and published by Royal Society of Chemistry. This book was released on 2015-11-06 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a concise and inexpensive introduction for an undergraduate course in glass science and technology. The level of the book has deliberately been maintained at the introductory level to avoid confusion of the student by inclusion of more advanced material, and is unique in that its text is limited to the amount suitable for a one term course for students in materials science, ceramics or inorganic chemistry. The contents cover the fundamental topics of importance in glass science and technology, including glass formation, crystallization, phase separation and structure of glasses. Additional chapters discuss the most important properties of glasses, including discussion of physical, optical, electrical, chemical and mechanical properties. A final chapter provides an introduction to a number of methods used to form technical glasses, including glass sheet, bottles, insulation fibre, optical fibres and other common commercial products. In addition, the book contains discussion of the effects of phase separation and crystallization on the properties of glasses, which is neglected in other texts. Although intended primarily as a textbook, Introduction to Glass Science and Technology will also be invaluable to the engineer or scientist who desires more knowledge regarding the formation, properties and production of glass.

Download or read book Classic and Advanced Ceramics written by Robert B. Heimann and published by John Wiley & Sons. This book was released on 2010-04-16 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on the author's lectures to graduate students of geosciences, physics, chemistry and materials science, this didactic handbook covers basic aspects of ceramics such as composition and structure as well as such advanced topics as achieving specific functionalities by choosing the right materials. The focus lies on the thermal transformation processes of natural raw materials to arrive at traditional structural ceramics and on the general physical principles of advanced functional ceramics. The book thus provides practice-oriented information to readers in research, development and engineering on how to understand, make and improve ceramics and derived products, while also serving as a rapid reference for the practitioner. The choice of topics and style of presentation make it equally useful for chemists, materials scientists, engineers and mineralogists.

Download or read book Semiconductor Packaging written by Andrea Chen and published by CRC Press. This book was released on 2016-04-19 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: In semiconductor manufacturing, understanding how various materials behave and interact is critical to making a reliable and robust semiconductor package. Semiconductor Packaging: Materials Interaction and Reliability provides a fundamental understanding of the underlying physical properties of the materials used in a semiconductor package. By tying together the disparate elements essential to a semiconductor package, the authors show how all the parts fit and work together to provide durable protection for the integrated circuit chip within as well as a means for the chip to communicate with the outside world. The text also covers packaging materials for MEMS, solar technology, and LEDs and explores future trends in semiconductor packages.

Download or read book Corrosion Control for Offshore Structures written by Ramesh Singh and published by Gulf Professional Publishing. This book was released on 2014-08-12 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: A variable game changer for those companies operating in hostile, corrosive marine environments, Corrosion Control for Offshore Structures provides critical corrosion control tips and techniques that will prolong structural life while saving millions in cost. In this book, Ramesh Singh explains the ABCs of prolonging structural life of platforms and pipelines while reducing cost and decreasing the risk of failure. Corrosion Control for Offshore Structures places major emphasis on the popular use of cathodic protection (CP) combined with high efficiency coating to prevent subsea corrosion. This reference begins with the fundamental science of corrosion and structures and then moves on to cover more advanced topics such as cathodic protection, coating as corrosion prevention using mill applied coatings, field applications, and the advantages and limitations of some common coating systems. In addition, the author provides expert insight on a number of NACE and DNV standards and recommended practices as well as ISO and Standard and Test Methods. Packed with tables, charts and case studies, Corrosion Control for Offshore Structures is a valuable guide to offshore corrosion control both in terms of its theory and application. Prolong the structural life of your offshore platforms and pipelines Understand critical topics such as cathodic protection and coating as corrosion prevention with mill applied coatings Gain expert insight on a number of NACE and DNV standards and recommended practices as well as ISO and Standard Test Methods.

Download or read book The Superalloys written by Roger C. Reed and published by Cambridge University Press. This book was released on 2008-07-31 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superalloys are unique high-temperature materials used in gas turbine engines, which display excellent resistance to mechanical and chemical degradation. This book introduces the metallurgical principles which have guided their development. Suitable for graduate students and researchers, it includes exercises and additional resources at www.cambridge.org/9780521859042.

Download or read book Sol Gel Technologies for Glass Producers and Users written by Michel Andre Aegerter and published by Springer Science & Business Media. This book was released on 2013-03-19 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sol-Gel Techniques for Glass Producers and Users provides technological information, descriptions and characterizations of prototypes, or products already on the market, and illustrates advantages and disadvantages of the sol-gel process in comparison to other methods. The first chapter entitled "Wet Chemical Technology" gives a summary of the basic principles of the sol-gel chemistry. The most promising applications are related to coatings. Chapter 2 describes the various "Wet Chemical Coating Technologies" from glass cleaning to many deposition and post-coating treatment techniques. These include patterning of coatings through direct or indirect techniques which have became very important and for which the sol-gel processing is particularly well adapted. Chapter 3 entitled "Bulk Glass Technologies" reports on the preparation of special glasses for different applications. Chapter 4 entitled "Coatings and Materials Properties" describes the properties of the different coatings and the sol-gel materials, fibers and powders. The chapter also includes a section dedicated to the characterization techniques especially applied to sol-gel coatings and products.

Download or read book High Temperature Oxidation Protection of Tungsten written by and published by . This book was released on 1969 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: