Thermal Barrier Coatings

Thermal Barrier Coatings
Author: Hongbo Guo
Publisher: Woodhead Publishing
Total Pages: 490
Release: 2023-01-18
Genre: Science
ISBN: 0128190280

Thermal Barrier Coatings, Second Edition plays a critical role in counteracting the effects of corrosion and degradation of exposed materials in high-temperature environments such as gas turbine and aero-engines. This updated edition reviews recent advances in the processing and performance of thermal barrier coatings, as well as their failure mechanisms. Novel technologies for the manufacturing of thermal barrier coatings (TBCs) such as plasma spray-physical vapor deposition and suspension plasma spray, are covered, as well as severe degradation of TBCs caused by CMAS attack. In addition to discussions of new materials and technologies, an outlook about next generation TBCs, including T/EBCs is discussed.This edition will provide the fundamental science and engineering of thermal barrier coatings for researchers in the field of TBCs, as well as students looking for a tutorial. Includes coverage of emerging materials, such as rare-earth doped ceramics Presents the latest on plasma spray-physical vapor deposition and suspension (solution precursor) Discusses the degradation of TBCs caused by CMAS attack and its protection Looks at thermally environmental barrier coatings, interdiffusion and diffusion barrier

Processing and Properties of Advanced Ceramics and Composites VII

Processing and Properties of Advanced Ceramics and Composites VII
Author: Morsi M. Mahmoud
Publisher: John Wiley & Sons
Total Pages: 454
Release: 2015-10-05
Genre: Technology & Engineering
ISBN: 1119183871

This volume contains 40 papers from the following 10 Materials Science and Technology (MS&T'14) symposia: Rustum Roy Memorial Symposium: Processing and Performance of Materials Using Microwaves, Electric and Magnetic Fields, Ultrasound, Lasers, and Mechanical Work Advances in Dielectric Materials and Electronic Devices Innovative Processing and Synthesis of Ceramics, Glasses and Composites Advances in Ceramic Matrix Composites Sintering and Related Powder Processing Science and Technology Advanced Materials for Harsh Environments Thermal Protection Materials and Systems Advanced Solution Based Processing for Ceramic Materials Controlled Synthesis, Processing, and Applications of Structure and Functional Nanomaterials Surface Protection for Enhanced Materials Performance

Effect of Manufacturing Parameters on TBC Systems Cyclic Oxidation Lifetime

Effect of Manufacturing Parameters on TBC Systems Cyclic Oxidation Lifetime
Author: Laura Chirivi
Publisher:
Total Pages:
Release: 2011
Genre:
ISBN:

Aero-gas turbine engines have to meet reliability, durability and fuel e ciency requirements. High turbine inlet temperatures may contribute to minimise fuel consumption and, in turn, environmental impact of the engine. Over the past few years, new designs and engine optimisation have allowed increase of such temperatures at a rate of 15 C per year, with maximum operating temperatures currently exceeding 1650 C. Ceramic coatings (also known as Thermal Barrier Coatings or TBCs) in conjunction with advanced cooling technologies are adopted to protect stator vanes and high pressure turbine blades from excessive thermal loads. Nevertheless, even with these protections in place, such components may experience a continuous service temperature of 1050 C, and peak temperatures as high as 1200 C. Therefore, it is vital that engine rotating components are able to maintain their mechanical properties at high temperature, while being able to withstand thermal loads and having su cient oxidation resistance to preserve the integrity of the ceramic coating, and eventually reaching desired component lives. Such strict requirements can be met with the use of complex Thermal Barrier Coat- ing systems or TBC systems; these consist of a nickel-based superalloy component which is rst coated with an environmental resistant layer (identi ed as bond coat ) and then with a ceramic coating. As its name suggests, the bond coat must not only protect the metallic substrate against oxidation and/or corrosion but must also provide su - cient bonding of the ceramic top layer to the metallic substrate. This goal is achieved through the formation of a further layer between the bond coat and the ceramic. In gas turbine applications, such a layer (identi ed as Thermally Grown Oxide or TGO) is an alumina scale which is the result of the bond coat oxidation during the ceramic deposition. During engine service, several time and cycle related phenomena occur within the TBC system which eventually lead the system to failure by spallation of the top coat. Aero-gas turbine engines have to meet reliability, durability and fuel e ciency requirements. High turbine inlet temperatures may contribute to minimise fuel consumption and, in turn, environmental impact of the engine. Over the past few years, new designs and engine optimisation have allowed increase of such temperatures at a rate of 15 C per year, with maximum operating temperatures currently exceeding 1650 C. Ceramic coatings (also known as Thermal Barrier Coatings or TBCs) in conjunction with advanced cooling technologies are adopted to protect stator vanes and high pressure turbine blades from excessive thermal loads. Nevertheless, even with these protections in place, such components may experience a continuous service temperature of 1050 C, and peak temperatures as high as 1200 C. Therefore, it is vital that engine rotating components are able to maintain their mechanical properties at high temperature, while being able to withstand thermal loads and having su cient oxidation resistance to preserve the integrity of the ceramic coating, and eventually reaching desired component lives. Such strict requirements can be met with the use of complex Thermal Barrier Coat- ing systems or TBC systems; these consist of a nickel-based superalloy component which is rst coated with an environmental resistant layer (identi ed as bond coat ) and then with a ceramic coating. As its name suggests, the bond coat must not only protect the metallic substrate against oxidation and/or corrosion but must also provide su - cient bonding of the ceramic top layer to the metallic substrate. This goal is achieved through the formation of a further layer between the bond coat and the ceramic. In gas turbine applications, such a layer (identi ed as Thermally Grown Oxide or TGO) is an alumina scale which is the result of the bond coat oxidation during the ceramic deposition. During engine service, several time and cycle related phenomena occur within the TBC system which eventually lead the system to failure by spallation of the top coat. Aero-gas turbine engines have to meet reliability, durability and fuel e ciency requirements. High turbine inlet temperatures may contribute to minimise fuel consumption and, in turn, environmental impact of the engine. Over the past few years, new designs and engine optimisation have allowed increase of such temperatures at a rate of 15 C per year, with maximum operating temperatures currently exceeding 1650 C. Ceramic coatings (also known as Thermal Barrier Coatings or TBCs) in conjunction with advanced cooling technologies are adopted to protect stator vanes and high pressure turbine blades from excessive thermal loads. Nevertheless, even with these protections in place, such components may experience a continuous service temperature of 1050 C, and peak temperatures as high as 1200 C. Therefore, it is vital that engine rotating components are able to maintain their mechanical properties at high temperature, while being able to withstand thermal loads and having su cient oxidation resistance to preserve the integrity of the ceramic coating, and eventually reaching desired component lives. Such strict requirements can be met with the use of complex Thermal Barrier Coat- ing systems or TBC systems; these consist of a nickel-based superalloy component which is rst coated with an environmental resistant layer (identi ed as bond coat ) and then with a ceramic coating. As its name suggests, the bond coat must not only protect the metallic substrate against oxidation and/or corrosion but must also provide su - cient bonding of the ceramic top layer to the metallic substrate. This goal is achieved through the formation of a further layer between the bond coat and the ceramic. In gas turbine applications, such a layer (identi ed as Thermally Grown Oxide or TGO) is an alumina scale which is the result of the bond coat oxidation during the ceramic deposition. During engine service, several time and cycle related phenomena occur within the TBC system which eventually lead the system to failure by spallation of the top coat. This may have catastrophic consequences as the uncoated component would face temperatures higher than the melting point of the constituent metal. This is avoided by strict maintenance regimes based on the minimum expected life of the coating. While essential for safeguarding the aircraft, this approach prevents the TBC systems from being used to their full potential. This study investigates possible optimisation methods of the manufacturing process of TBC systems, with the aim of improving reproducibility in terms of time to failure, thereby extending their minimum life expectancy and reliability. Two di erent types of TBC systems are studied: a TBC system with a Platinum-di used bond coat and a TBC system with a Platinum-modi ed aluminide bond coat. The work focuses on the e ects due to modi cation of process parameters (varied within industrially accepted range) on the TBC systems lifetime in laboratory scale cyclic oxidation tests. Experimental results show that accurate monitoring of the metal substrate surface nish as well as of the Pt layer morphology and ceramic deposition temperature may result in a dramatic improvement in life expectancy of the system, up to sevenfold when compared to control samples, or threefold if compared to commercial coatings.

High Temperature Coatings

High Temperature Coatings
Author: Sudhangshu Bose
Publisher: Butterworth-Heinemann
Total Pages: 418
Release: 2017-11-27
Genre: Technology & Engineering
ISBN: 0128047437

High Temperature Coatings, Second Edition, demonstrates how to counteract the thermal effects of rapid corrosion and degradation of exposed materials and equipment that can occur under high operating temperatures. This is the first true practical guide on the use of thermally protective coatings for high-temperature applications, including the latest developments in materials used for protective coatings. It covers the make-up and behavior of such materials under thermal stress and the methods used for applying them to specific types of substrates, as well as invaluable advice on inspection and repair of existing thermal coatings. With his long experience in the aerospace gas turbine industry, the author has compiled the very latest in coating materials and coating technologies, as well as hard-to-find guidance on maintaining and repairing thermal coatings, including appropriate inspection protocols. The book is supplemented with the latest reference information and additional support to help readers find more application- and industry-type coatings specifications and uses. Offers an overview of the underlying fundamental concepts of thermally-protective coatings, including thermodynamics, energy kinetics, crystallography and equilibrium phases Covers essential chemistry and physics of underlying substrates, including steels, nickel-iron alloys, nickel-cobalt alloys and titanium alloys Provides detailed guidance on a wide variety of coating types, including those used against high temperature corrosion and oxidative degradation and thermal barrier coatings

The Superalloys

The Superalloys
Author: Roger C. Reed
Publisher: Cambridge University Press
Total Pages: 363
Release: 2008-07-31
Genre: Technology & Engineering
ISBN: 1139458639

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.

Thermal Spray Fundamentals

Thermal Spray Fundamentals
Author: Pierre L. Fauchais
Publisher: Springer Science & Business Media
Total Pages: 1587
Release: 2014-01-24
Genre: Technology & Engineering
ISBN: 0387689915

This book provides readers with the fundamentals necessary for understanding thermal spray technology. Coverage includes in-depth discussions of various thermal spray processes, feedstock materials, particle-jet interactions, and associated yet very critical topics: diagnostics, current and emerging applications, surface science, and pre and post-treatment. This book will serve as an invaluable resource as a textbook for graduate courses in the field and as an exhaustive reference for professionals involved in thermal spray technology.