Download or read book Performance of MCrAlX coatings written by Pimin Zhang and published by Linköping University Electronic Press. This book was released on 2019-11-04 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: MCrAlY coatings (M=Ni and/or Co) are widely used for the protection of superalloy components against oxidation and hot corrosion in the hot sections of gas turbines. The drive for coating systems to bestow adequate oxidation and corrosion resistance upon the components becomes urgent as an inevitable result of the necessary improvement in engine combustion efficiency and service lifetime. Through the careful design of the composition, MCrAlY coating performance can be optimized to meet the needs under different service conditions and component materials, therefore, “MCrAlX”, with “X” stands for the minor alloying elements, is used to highlight the effect. In the present thesis, the performance of new MCrAlX coatings is investigated with respect to oxidation, hot corrosion and interactions between coating-superalloy substrates. Oxidation of MCrAlX coatings can be generally categorized into initial, steady and close-to-end stages. Coating performance can be affected by various factors at different stages, therefore, experiments were designed by targeting the oxidation stages. Investigation on the initial stage oxidation behavior of MCrAlY coatings with post-deposition surface treatments reveals the different growth mechanisms of alumina scales. Surface treatments significantly reduce the alumina growth rate by suppressing transient alumina development and aiding the early formation of ?-Al2O3, which improves the long-term oxidation performance of the coating. Similarly, the modification of minor alloy elements in MCrAlX coatings also serves the purpose. The oxidation behavior of new MCrAlX coatings was investigated at the steady oxidation stage, followed by the microstructure observation, thermodynamic and kinetic simulations. As an alternative reactive element addition of Y, Ce shows a negative effect on the formation of columnar alumina scales of high strain tolerance. In comparison, Fe or Ru addition shows no influence on alumina growth, rather than strengthening the phase stability in the coating and reducing the interdiffusion between coating-substrate through different mechanisms. As the oxidation proceeds to the close-to-end stage, a reliable criterion to estimate the capability of coating to form ?-Al2O3 is of great importance to accurately evaluate coating lifetime. A temperature-dependent critical Al-activity criterion was proposed to better predict the formation of a continuous ?-Al2O3 scale based on correction of elemental activity using thermodynamic database to replace the empirical Al-concentration based criterion. Severe interdiffusion occurs between coating-substrate during high temperature oxidation, accelerating the degradation of the system. Interdiffusion behavior of diffusion couples of superalloys-MCrAlX coatings were examined. It is highlighted that the recrystallization of superficial layer of the substrate contributes to the secondary reaction zone formation and element interdiffusion controls subsequent zone thickening. Study on Type I hot corrosion behavior of new MCrAlX coatings shows that the addition of Fe has no influence on basic fluxing reactions before severe Al depletion from the coating occurs. Instead, it boosts the “effective” Al supply of coating by shifting the equilibrium concentration of Al in the ? phase to a low Al level. Besides, the pre-mature coating degradation at the coating-substrate interface was due to the fast growth of corrosion products from substrate induced large local volume expansions, resulting in early coating spallation. MCrAlY ytbeläggningar (M=Ni och/eller Co) används ofta för att skydda komponenter tillverkade av superlegeringar mot oxidation samt högtemperaturskorrosion i de heta gasturbindelarna. Förbättrad förbränningseffektivitet och livslängd hos gasturbiner, gör att ytbeläggningssystemen måste besitta adekvata oxidations- och korrosionsmotstånd. Genom att omsorgsfullt utforma den kemiska sammansättningen hos MCrAlY ytbeläggningar kan deras prestanda optimeras för att möta kraven från olika driftförhållanden samt olika substratmaterial, därför används beteckningen "MCrAlX" för att belysa förändringar av den kemiska kompositionen, där "X" står för reaktiva legeringsämnen som tillsätts i mindre mängder. I denna avhandling undersöks prestandan hos en ny MCrAlX ytbeläggning med hänsyn till oxidation, högtemperaturskorrosion och interaktionen mellan ytbeläggningen och superlegeringssubstratet. Oxidation av MCrAlX ytbeläggningar kan generellt kategoriseras i tre faser; initiala, stabila och nära-slutet fasen. Ytbeläggningens prestanda kan påverkas av olika faktorer vid de olika faserna, därför utformades olika experiment för att undersöka de olika oxidationsfaserna. Undersökningen av den initiala fasen av oxidationsbeteendet hos MCrAlX ytbeläggningar som genomgått ytbehandlingar efter ytbeläggningsdeponeringen avslöjade olika tillväxtmekanismer hos aluminiumoxidskikten. Aluminiumoxidens tillväxthastighet reducerades signifikant av ytbehandlingarna, detta genom att undertrycka utvecklingen av övergående aluminiumoxid och bistå den tidiga tillväxten av ?-Al2O3, vilket förbättrar ytbeläggningens oxidationsprestanda långsiktigt. De reaktiva legeringsämnena som tillsätts i mindre mänger påverkar ytbeläggningens oxidationsprestanda på liknande sätt. Oxidationsbeteendet hos de nya MCrAlX ytbeläggningarna i den stabila fasen följdes av mikrostrukturundersökning, termodynamiska och kinetiska simuleringar. Det framkom att Ce visar en negativ effekt på bildandet av kolumnära aluminiumoxidskikt med hög töjningstolerans som alternativt reaktivt legeringsämne till Y. Jämförelsevis ger Fe- eller Ru-tillsatser ingen påverkan på aluminiumoxidtillväxten, förutom att det förstärker fasstabiliteten i ytbeläggningen samt genom olika mekanismer reducerar interdiffusionen mellan ytbeläggningen och substratet. När oxidationsprocessen kommit till nära-slutet fasen, är det viktigt att uppskatta kapaciteten hos en ytbeläggning att bilda ?-Al2O3, detta då det är ett tillförlitligt kriterium för att noggrant kunna utvärdera ytbeläggningens livslängd. Därför föreslogs ett temperaturberoende kriterium för kritisk Al-aktivitet för att bättre kunna förutsäga bildandet av ett kontinuerligt ?-Al2O3-skikt. Kriteriet baserades på korrigering av legeringsämnens aktivitet genom att använda en termodynamisk databas, detta för att ersätta det empiriska Al-koncentrations baserade kriteriet. Vid högtemperatursoxidation sker en omfattande interdiffusion mellan ytbeläggningen och substratet, vilket accelererar degraderingen av ytbeläggningssystemet. Därför har interdiffusionsbeteendet mellan superlegeringssubstratet och MCrAlX ytbeläggningen undersökts i denna avhandling. Det framkom att rekristallisationen av ytliga skikt av substratet bidrar till formationen av den sekundära reaktionszonen och att interdiffusion kontrollerar zonens efterföljande tjocklektillväxt. Undersökningen av Typ I högtemperaturskorrosionsbeteendet hos en ny MCrAlX ytbeläggning visar att legeringstillägg av Fe inte påverkar de grundläggande flödesreaktionerna innan en kritisk Al utarmning sker i ytbeläggningen. Istället stimulerar det tillförseln av Al genom att skifta jämviktskoncentrationen av Al i ? fasen till en låg nivå av Al. Det framkom också att den tidiga degraderingen av ytbeläggningen vid gränsskiktet mellan ytbeläggningen och substratet kommer av att den snabba tillväxten av korrosionsprodukter från substratet inducerade en stor lokal volymsutvidgning, vilket ledde till tidig ytbeläggningsspallation.
Download or read book Oxidation behaviour of MCrAlX coatings written by Pimin Zhang and published by Linköping University Electronic Press. This book was released on 2018-02-12 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: MCrAlY coatings (M=Ni and/or Co) have been widely used for the protection of superalloy components against oxidation and hot corrosion in the hot sections of gas turbines. The drive to improve engine combustion efficiency while reducing emissions by increasing the operation temperature brings a big challenge for coating design. As a result, the need for improvement of MCrAlY coatings for better oxidation resistance is essential. Formation of a stable, dense, continuous, and slow-growing ?-Al2O3 layer, on the MCrAlY coating surface, is the key to oxidation protection, since the protective ?-Al2O3 scale offers superior oxidation resistance due to its lower oxygen-diffusion rate as compared with other oxides. The ability of a MCrAlY coating to form and maintain such a protective scale depends on the coating composition and microstructure, and can be improved through optimization of deposition parameters, modification of coating surface conditions, and so on. Part of this thesis work focuses on studying the effect of post-deposition surface treatments on the oxidation behavior of MCrAlX coatings (X can be yttrium and/or other minor alloying elements). The aim is to gain fundamental understanding of alumina scale evolution during oxidation which is important for achieving improved oxidation resistance of MCrAlX coatings. Oxide scale formed on coatings at initial oxidation stage and the effect of surface treatment were investigated by a multi-approach study combining photo-stimulated luminescence, microstructural observation and weight gain. Results showed that both mechanically polished and shot-peened coatings exhibited superior performance due to rapid formation of ?-Al2O3 fully covering the coating and suppressing growth of transient alumina, assisted by the high density of ?-Al2O3 nuclei on surface treatment induced defects. The early development of a two-layer alumina scale, consisting of an inward-grown inner ?-Al2O3 layer and an outer layer transformed from outward-grown transient alumina, resulted in a higher oxide growth rate of the as-sprayed coating. The positive effect of the surface treatments on retarding oxide scale growth and suppressing formation of spinel was also observed in oxidation test up to 1000 hrs. As the oxidation proceeds to the close-to-end stage, a reliable criterion to estimate the capability of coating to form ?-Al2O3 is of great importance to accurately evaluate coating lifetime, which is the aim of the other part of the thesis work. Survey of published results on a number of binary Ni-Al and ternary Ni-Cr-Al, Ni-Al-Si systems shows that the empirical Al-concentration based criterion is inadequate to properly predict the formation of a continuous ?-Al2O3 scale. On the other hand, correlating the corresponding Al-activity data, calculated from measured chemical compositions using the Thermo-Calc software, to the experimental oxidation results has revealed a temperature dependent, critical Al-activity value for forming continuous ?-Al2O3 scale. To validate the criterion, long-term oxidation tests were performed on five MCrAlX coatings with varying compositions and the implementation of the Al-activity based criterion on these coatings successfully predicted ?-Al2O3 formation, showing a good agreement with experiment results.
Download or read book Oxidation and Corrosion of New MCrAlX Coatings written by Kang Yuan and published by . This book was released on 2014 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design of Thermal Barrier Coatings written by Mohit Gupta and published by Springer. This book was released on 2015-05-05 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book details the relationships between microstructure, interface roughness, and properties of thermal barrier coatings. The author proposes a method for the reduction of the thermal conductivity of the ceramic layer in order to increase the lifetime of thermal barrier coatings. He includes models for the optimization of ceramic layer microstructure and interface roughness.
Download or read book High Temperature Coatings written by Sudhangshu Bose and published by Butterworth-Heinemann. This book was released on 2017-11-27 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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
Download or read book Advances in Material Science and Engineering written by Seyed Sattar Emamian and published by Springer Nature. This book was released on 2022-10-05 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights the recent research works on mechanical, manufacturing and plant engineering presented during the 7th International Conference on Mechanical, Manufacturing and Plant Engineering (ICMMPE 2021) held on 29th November 2021. It highlights the latest advances in the emerging areas, brings together researchers and professionals in the field and provides a valuable platform for exchanging ideas and fostering collaboration. Addressing real-world problems concerning joining technologies that are at the heart of various manufacturing sectors, the respective papers present the outcomes of the latest experimental and numerical work on problems in soldering, arc welding and solid-state joining technologies.
Download or read book Advanced Materials written by Ajit Behera and published by Springer Nature. This book was released on 2021-11-21 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a thorough introduction to the essential topics in modern materials science. It brings together the spectrum of materials science topics, spanning inorganic and organic materials, nanomaterials, biomaterials, and alloys within a single cohesive and comprehensive resource. Synthesis and processing techniques, structural and crystallographic configurations, properties, classifications, process mechanisms, applications, and related numerical problems are discussed in each chapter. End-of-chapter summaries and problems are included to deepen and reinforce the reader's comprehension. Provides a cohesive and comprehensive reference on a wide range of materials and processes in modern materials science; Presents material in an engaging manner to encourage innovative practices and perspectives; Includes chapter summaries and problems at the end of every chapter for reinforcement of concepts.
Download or read book Oxidation Behaviour of MCrAlX Coatings written by Pimin Zhang and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coatings for Harsh Environments written by Shiladitya Paul and published by MDPI. This book was released on 2020-11-13 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: The operation of numerous components that are critical to safety in industries around the world relies on protective coatings. These coatings often allow process equipment to serve a purpose in environments well beyond the operational limit of the uncoated components. Durability, ease of application, repairability, reliability and long-term performance of such coatings are all key to their application. Therefore, this book, Coatings for Harsh Environments, is devoted to research and review articles on the metallic, non-metallic and composite coatings used in aggressive environments. In particular, the topics of interest include, but are not limited to: coatings for high temperature and molten salt applications; thermal spray and cold spray coatings for aggressive environments; corrosion, wear and cavitation resistant coatings; coatings for mitigating marine corrosion; coatings for chemical and petrochemical plants; thermal barrier coatings.
Download or read book Aerospace Alloys written by Stefano Gialanella and published by Springer Nature. This book was released on 2019-10-30 with total page 583 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an up-to-date overview on the main classes of metallic materials currently used in aeronautical structures and propulsion engines and discusses other materials of potential interest for structural aerospace applications. The coverage encompasses light alloys such as aluminum-, magnesium-, and titanium-based alloys, including titanium aluminides; steels; superalloys; oxide dispersion strengthened alloys; refractory alloys; and related systems such as laminate composites. In each chapter, materials properties and relevant technological aspects, including processing, are presented. Individual chapters focus on coatings for gas turbine engines and hot corrosion of alloys and coatings. Readers will also find consideration of applications in aerospace-related fields. The book takes full account of the impact of energy saving and environmental issues on materials development, reflecting the major shifts that have occurred in the motivations guiding research efforts into the development of new materials systems. Aerospace Alloys will be a valuable reference for graduate students on materials science and engineering courses and will also provide useful information for engineers working in the aerospace, metallurgical, and energy production industries.
Download or read book Materials Corrosion and Protection written by Yongchang Huang and published by Walter de Gruyter GmbH & Co KG. This book was released on 2018-02-05 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces corrosion mechanisms and protection technologies for metallic and non-metallic materials. A focus lies on the protection of high-tech materials with applications in space and environments exposed to unclear radiation and biological hazards. The determination, measurement and control of different corrosion mechanisms are discussed in detail. Combining theories with case studies, it is an essential reference for material scientists and engineers.
Download or read book Manufacturing Engineering Technology written by Will Craig & Ashley Leonard and published by Scientific e-Resources. This book was released on 2019-10-04 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Thermal Energy Storage Systems written by Luisa F. Cabeza and published by Woodhead Publishing. This book was released on 2020-10-28 with total page 799 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Thermal Energy Storage Systems, 2nd edition, presents a fully updated comprehensive analysis of thermal energy storage systems (TES) including all major advances and developments since the first edition published. This very successful publication provides readers with all the information related to TES in one resource, along with a variety of applications across the energy/power and construction sectors, as well as, new to this edition, the transport industry. After an introduction to TES systems, editor Dr. Prof. Luisa Cabeza and her team of expert authors consider the source, design and operation of the use of water, molten salts, concrete, aquifers, boreholes and a variety of phase-change materials for TES systems, before analyzing and simulating underground TES systems. This edition benefits from 5 new chapters covering the most advanced technologies including sorption systems, thermodynamic and dynamic modelling as well as applications to the transport industry and the environmental and economic aspects of TES. It will benefit researchers and academics of energy systems and thermal energy storage, construction engineering academics, engineers and practitioners in the energy and power industry, as well as architects of plants and storage systems and R&D managers. Includes 5 brand new chapters covering Sorption systems, Thermodynamic and dynamic models, applications to the transport sector, environmental aspects of TES and economic aspects of TES All existing chapters are updated and revised to reflect the most recent advances in the research and technologies of the field Reviews heat storage technologies, including the use of water, molten salts, concrete and boreholes in one comprehensive resource Describes latent heat storage systems and thermochemical heat storage Includes information on the monitoring and control of thermal energy storage systems, and considers their applications in residential buildings, power plants and industry
Download or read book Superalloy written by Fouad Sabry and published by One Billion Knowledgeable. This book was released on 2022-01-17 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: What Is Superalloy A superalloy, or high-performance alloy, is an alloy with the ability to operate at a high fraction of its melting point. Several key characteristics of a superalloy are excellent mechanical strength, resistance to thermal creep deformation, good surface stability, and resistance to corrosion or oxidation. How You Will Benefit (I) Insights, and validations about the following topics: Chapter 1: Superalloy Chapter 2: Oxide dispersion-strengthened alloy Chapter 3: Titanium aluminide Chapter 4: Alloy Chapter 5: Strength of materials Chapter 6: Creep (deformation) Chapter 7: Corrosion Chapter 8: Redox (II) Answering the public top questions about superalloy. (III) Real world examples for the usage of superalloy in many fields. (IV) 17 appendices to explain, briefly, 266 emerging technologies in each industry to have 360-degree full understanding of superalloy' technologies. Who This Book Is For Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of superalloy.
Download or read book CO2 Free Ammonia as an Energy Carrier written by Ken-ichi Aika and published by Springer Nature. This book was released on 2022-11-01 with total page 679 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes important findings in intensive studies conducted in Japan on ammonia as an energy carrier. It illustrates an advanced solar-heat capture system and storage materials at 600°C and hydrogen production with SOECs and a new IS method through the use of heat. New industrial ammonia catalysts and a demonstration process that started running in Fukushima are also introduced. Advanced ammonia decomposition catalysts and the process that were developed for use by the hydrogen station are presented. An advanced direct ammonia fuel cell was developed and the base data are shown. The book explains that ammonia is used as a fuel for industrial applications because its burning can be controlled without emitting extra NOx in the gas turbine and the real coal co-fired power plant. These breakthroughs have made a strong impact in the world as a practical technology for CO2 reduction. Also provided here are the scientific and industrial backgrounds as well as the environmental assessment and economic evaluation for the future.This book will be helpful for all who are interested in energy technology—researchers, students, and strategy planners at companies and in the government.
Download or read book Advanced Thermally Assisted Surface Engineering Processes written by Ramnarayan Chattopadhyay and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surfaces are the bounding faces of solids. The interaction of component surface with the working environment results in wear and corrosion. Estimated loss due to wear and corrosion in the USA is around $500 billion. Engineered surfaces are the key to the reduction of losses due to wear and corrosion. There are surface engineering books on specific processes such as thermal spraying and vapor phase deposition or about specific heat sources such as plasma or laser. However, there are few, if any, covering the whole range of advanced surface engineering processes. Advanced Thermally Assisted Surface Engineering Processes has been structured to provide assistance and guidance to the engineers, researchers and students in choosing the right process from the galaxy of newer surface engineering techniques using advanced heat sources.
Download or read book Introduction to Materials for Advanced Energy Systems written by Colin Tong and published by Springer. This book was released on 2018-12-12 with total page 911 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first of its kind text enables today’s students to understand current and future energy challenges, to acquire skills for selecting and using materials and manufacturing processes in the design of energy systems, and to develop a cross-functional approach to materials, mechanics, electronics and processes of energy production. While taking economic and regulatory aspects into account, this textbook provides a comprehensive introduction to the range of materials used for advanced energy systems, including fossil, nuclear, solar, bio, wind, geothermal, ocean and hydropower, hydrogen, and nuclear, as well as thermal energy storage and electrochemical storage in fuel cells. A separate chapter is devoted to emerging energy harvesting systems. Integrated coverage includes the application of scientific and engineering principles to materials that enable different types of energy systems. Properties, performance, modeling, fabrication, characterization and application of structural, functional and hybrid materials are described for each energy system. Readers will appreciate the complex relationships among materials selection, optimizing design, and component operating conditions in each energy system. Research and development trends of novel emerging materials for future hybrid energy systems are also considered. Each chapter is basically a self-contained unit, easily enabling instructors to adapt the book for coursework. This textbook is suitable for students in science and engineering who seek to obtain a comprehensive understanding of different energy processes, and how materials enable energy harvesting, conversion, and storage. In setting forth the latest advances and new frontiers of research, the text also serves as a comprehensive reference on energy materials for experienced materials scientists, engineers, and physicists. Includes pedagogical features such as in-depth side bars, worked-out and end-of- chapter exercises, and many references to further reading Provides comprehensive coverage of materials-based solutions for major and emerging energy systems Brings together diverse subject matter by integrating theory with engaging insights
