Guides researchers and practitioners toward developing highly reliable ceramic-matrix composites The book systematically introduces the thermomechanical fatigue behavior of fiber-reinforced ceramic-matrix composites (CMCs) and environmental barrier coatings, including cyclic loading/unloading tensile behavior, cyclic fatigue behavior, dwell-fatigue behavior, thermomechanical fatigue behavior, and interface degradation behavior. It discusses experimental verification of CMCs and explains how to determine the thermomechanical properties. It also presents damage evolution models, lifetime prediction methods, and interface degradation rules. Thermomechanical Fatigue of Ceramic-Matrix Composites offers chapters covering unidirectional ceramic-matrix composites and cross-ply and 2D woven ceramic-matrix composites. For cyclic fatigue behavior of CMCs, it looks at the effects of fiber volume fraction, fatigue peak stress, fatigue stress ratio, matrix crack spacing, matrix crack mode, and woven structure on fatigue damage evolution. Both the Dwell-fatigue damage evolution and lifetime predictions models are introduced in the next chapter. Experimental comparisons of the cross-ply SiC/MAS composite, 2D SiC/SiC composite, and 2D NextelTM 720/Alumina composite are also included. Remaining sections examine: thermomechanical fatigue hysteresis loops; in-phase thermomechanical fatigue damage; out-of-phase thermomechanical fatigue; interface degradation models; and much more. -Offers unique content dedicated to thermomechanical fatigue behavior of ceramic-matrix composites (CMCs) and environmental barrier coatings -Features comprehensive data tables and experimental verifications -Covers a highly application-oriented subject?CMCs are being increasingly utilized in jet engines, industrial turbines, and exhaust systems Thermomechanical Fatigue of Ceramic-Matrix Composites is an excellent book for developers and users of CMCs, as well as organizations involved in evaluation and characterization of CMCs. It will appeal to materials scientists, construction engineers, process engineers, and mechanical engineers.
This book investigates the time-dependent behavior of fiber-reinforced ceramic-matrix composites (CMCs) at elevated temperatures. The author combines the time-dependent damage mechanisms of interface and fiber oxidation and fracture with the micromechanical approach to establish the relationships between the first matrix cracking stress, matrix multiple cracking evolution, tensile strength, tensile stress-strain curves and tensile fatigue of fiber-reinforced CMCs and time. Then, using damage models of energy balance, the fracture mechanics approach, critical matrix strain energy criterion, Global Load Sharing criterion, and hysteresis loops he determines the first matrix cracking stress, interface debonded length, matrix cracking density, fibers failure probability, tensile strength, tensile stress-strain curves and fatigue hysteresis loops. Lastly, he predicts the time-dependent mechanical behavior of different fiber-reinforced CMCs, i.e., C/SiC and SiC/SiC, using the developed approaches, in order to reduce the failure risk during the operation of aero engines. The book is intended for undergraduate and graduate students who are interested in the mechanical behavior of CMCs, researchers investigating the damage evolution of CMCs at elevated temperatures, and designers responsible for hot-section CMC components in aero engines.
The book "Interfaces of Ceramic-Matrix Composites" demonstrates the definition, function and type of the interface of ceramic-matrix composites and gives comprehensive investigations on the interface design, interface characterization, interface assessment, and interface damage law of both C/SiC and SiC/SiC ceramic-matrix composites subjected to tensile and fatigue loading at different testing conditions. Thereby, it helps material designers and engineers to better design ceramic-matrix composite components for applications.
Durability of Ceramic-Matrix Composites presents the latest information on these high-temperature structural materials and their outstanding advantages over more conventional materials, including their high specific strength, high specific modulus, high temperature resistance and good thermal stability. The critical nature of the application of these advanced materials makes it necessary to have a complete understanding of their characterization. This book focuses explicitly on the durability of CMCs and will be extremely valuable for materials scientists and engineers who are dealing with the simulation of durability response and fatigue of ceramic matrix composites. - Provides the latest theoretical and applied research in the field of ceramic matrix composites, particularly as it relates to usage in aerospace propulsion systems - Presents extensive information on the micromechanics of damage evolution, lifetime prediction and durability in ceramic matrix composites - Details parameter studies that are valuable for materials development and lifetime durability studies
This book presents the relationships between tensile damage and fracture, fatigue hysteresis loops, stress-rupture, fatigue life and fatigue limit stress, and stochastic loading stress. Ceramic-matrix composites (CMCs) possess low material density (i.e., only 1/4 - 1/3 of high-temperature alloy) and high-temperature resistance, which can reduce cooling air and improve structure efficiency. Understanding the failure mechanisms and internal damage evolution represents an important step to ensure reliability and safety of CMCs. This book investigates damage and fracture of fiber-reinforced ceramic-matrix composites (CMCs) subjected to stochastic loading, including: (1) tensile damage and fracture of fiber-reinforced CMCs subjected to stochastic loading; (2) fatigue hysteresis loops of fiber-reinforced CMCs subjected to stochastic loading; (3) stress rupture of fiber-reinforced CMCs with stochastic loading at intermediate temperature; (4) fatigue life prediction of fiber-reinforced CMCs subjected to stochastic overloading stress at elevated temperature; and (5) fatigue limit stress prediction of fiber-reinforced CMCs with stochastic loading. This book helps the material scientists and engineering designers to understand and master the damage and fracture of ceramic-matrix composites under stochastic loading.
This book focuses on mechanical hysteresis behavior in different fiber-reinforced ceramic-matrix composites (CMCs), including 1D minicomposites, 1D unidirectional, 2D cross-ply, 2D plain-woven, 2.5D woven, and 3D needle-punched composites. Ceramic-matrix composites (CMCs) are considered to be the lightweight high-temperature materials for hot-section components in aeroengines with the most potential. To improve the reliability and safety of CMC components during operation, it is necessary to conduct damage and failure mechanism analysis, and to develop models to predict this damage as well as fracture over lifetime - mechanical hysteresis is a key damage behavior in fiber-reinforced CMCs. The appearance of hysteresis is due to a composite’s internal damage mechanisms and modes, such as, matrix cracking, interface debonding, and fiber failure. Micromechanical damage models and constitutive models are developed to predict mechanical hysteresis in different CMCs. Effects of a composite’s constituent properties, stress level, and the damage states of the mechanical hysteresis behavior of CMCs are also discussed. This book also covers damage mechanisms, damage models and micromechanical constitutive models for the mechanical hysteresis of CMCs. This book will be a great resource for students, scholars, material scientists and engineering designers who would like to understand and master the mechanical hysteresis behavior of fiber-reinforced CMCs.
High Temperature Mechanical Behavior of Ceramic-Matrix Composites Covers the latest research on the high-temperature mechanical behavior of ceramic-matrix composites Due to their high temperature resistance, strength and rigidity, relatively light weight, and corrosion resistance, ceramic-matrix composites (CMCs) are widely used across the aerospace and energy industries. As these advanced composites of ceramics and various fibers become increasingly important in the development of new materials, understanding the high-temperature mechanical behavior and failure mechanisms of CMCs is essential to ensure the reliability and safety of practical applications. High Temperature Mechanical Behavior of Ceramic-Matrix Composites examines the behavior of CMCs at elevated temperature—outlining the latest developments in the field and presenting the results of recent research on different CMC characteristics, material properties, damage states, and temperatures. This up-to-date resource investigates the high-temperature behavior of CMCs in relation to first matrix cracking, matrix multiple cracking, tensile damage and fracture, fatigue hysteresis loops, stress-rupture, vibration damping, and more. This authoritative volume: Details the relationships between various high-temperature conditions and experiment results Features an introduction to the tensile, vibration, fatigue, and stress-rupture behavior of CMCs at elevated temperatures Investigates temperature- and time-dependent cracking stress, deformation, damage, and fracture of fiber-reinforced CMCs Includes full references and internet links to source material Written by a leading international researcher in the field, High Temperature Mechanical Behavior of Ceramic-Matrix Composites is an invaluable resource for materials scientists, surface chemists, organic chemists, aerospace engineers, and other professionals working with CMCs.
Nonlinear Damage Behavior of Ceramic Matrix Composites help readers [researchers, material scientists and design engineers] gain greater understanding on the damage mechanisms inside CMCs so they can better design components used in aeronautics and astronautics. Key areas addressed in the book include: the nonlinear damage behavior of ceramic-matrix composites, including damage mechanisms and models, nonlinear damage behavior of ceramic-matrix composites under tensile and fatigue loading, strain-rate dependent, stochastic loading dependent, and time dependent nonlinear damage behavior, and the effect of pre-exposure and thermal fatigue on non-linear damage behavior of ceramic-matrix composites. - Provides comprehensive coverage on damage mechanisms and models under tensile and cyclic fatigue loading which ultimately control nonlinear behavior - Covers nonlinear damage analyses of CMC components and experimental observations of damage evolution - Presents extensive knowledge on fracture mechanic principles used in the design of aerospace propulsion systems
This book focuses on the damage, fracture and fatigue of ceramic-matrix composites. It investigates tensile damage and fracture, fatigue hysteresis, and the properties of interfaces subjected to cyclic fatigue loading. Further, it predicts fatigue life at room and elevated temperatures using newly developed damage models and methods, and it analyzes and compares damage, fracture and fatigue behavior of different fiber performs: unidirectional, cross-ply, 2D and 2.5D woven. The developed models and methods can be used to predict the damage and lifetime of ceramic-matrix composites during applications on hot section components.Ceramic-matrix composites (CMCs) are high-temperature structural materials with the significant advantages of high specific strength, high specific modulus, high temperature resistance and good thermal stability, which play a crucial role in the development of high thrust weight ratio aero engines. The critical nature of the application of these advanced materials makes comprehensive characterization a necessity, and as such this book provides designers with essential information pertaining not only to the strength of the materials, but also to their fatigue and damage characteristics.
With the second-largest economy and rapidly growing military strength, China is now an emerging regional and global super power, which makes it confronted with a sudden increase in opportunities, pressures and conflicts in terms of international issues. This book gives a comprehensive and systematic introduction to the development of China’s diplomatic strategies since 1980s, which have been changed approximately every ten years to cope with the complicated and changing international situations. In 1980s, China took "non-alignment" to create a solid external environment for the reform and opening-up which had just been initiated. With the collapse of the Soviet Union, upheaval in Eastern Europe and the end of the Cold War in 1990s, China adopted the principle of "keeping a low profile and making some contributions", to adhere to the road of socialism while avoid making enemies. Nowadays, due to the continuous enhancement of national power and international status, China replaces "making some contributions" with "making positive actions", to get more actively involved in international affairs. This book will be a valuable reference for studies in China’s diplomacy and international relations. Readers interested in contemporary China will also be attracted by it.
This book focuses on the damage, fracture and fatigue of ceramic-matrix composites. It investigates tensile damage and fracture, fatigue hysteresis, and the properties of interfaces subjected to cyclic fatigue loading. Further, it predicts fatigue life at room and elevated temperatures using newly developed damage models and methods, and it analyzes and compares damage, fracture and fatigue behavior of different fiber performs: unidirectional, cross-ply, 2D and 2.5D woven. The developed models and methods can be used to predict the damage and lifetime of ceramic-matrix composites during applications on hot section components.Ceramic-matrix composites (CMCs) are high-temperature structural materials with the significant advantages of high specific strength, high specific modulus, high temperature resistance and good thermal stability, which play a crucial role in the development of high thrust weight ratio aero engines. The critical nature of the application of these advanced materials makes comprehensive characterization a necessity, and as such this book provides designers with essential information pertaining not only to the strength of the materials, but also to their fatigue and damage characteristics.
Ceramic matrix composites (CMCs) can withstand higher temperatures, reduce cooling airflow, improve turbine efficiency, and greatly reduce structural mass compared to the high temperature alloys. This book focuses on the matrix first/multiple cracking, crack opening and closure behavior in CMCs at high temperatures. While conducting in situ experimental observations to analyze the damage mechanisms and failure modes, the author develops micromechanical damage models and constitutive models to predict the first matrix cracking stress, multiple matrix cracking density, matrix crack opening displacement, and cracking closure stress at high temperatures. The effects of composite’s constituent properties, stress level, and ambient temperature on matrix cracking, opening, and closure are also discussed. This book will help material scientists and engineering designers to understand and master the matrix cracking and closure behavior of fiber-reinforced CMCs.
High Temperature Mechanical Behavior of Ceramic-Matrix Composites Covers the latest research on the high-temperature mechanical behavior of ceramic-matrix composites Due to their high temperature resistance, strength and rigidity, relatively light weight, and corrosion resistance, ceramic-matrix composites (CMCs) are widely used across the aerospace and energy industries. As these advanced composites of ceramics and various fibers become increasingly important in the development of new materials, understanding the high-temperature mechanical behavior and failure mechanisms of CMCs is essential to ensure the reliability and safety of practical applications. High Temperature Mechanical Behavior of Ceramic-Matrix Composites examines the behavior of CMCs at elevated temperature—outlining the latest developments in the field and presenting the results of recent research on different CMC characteristics, material properties, damage states, and temperatures. This up-to-date resource investigates the high-temperature behavior of CMCs in relation to first matrix cracking, matrix multiple cracking, tensile damage and fracture, fatigue hysteresis loops, stress-rupture, vibration damping, and more. This authoritative volume: Details the relationships between various high-temperature conditions and experiment results Features an introduction to the tensile, vibration, fatigue, and stress-rupture behavior of CMCs at elevated temperatures Investigates temperature- and time-dependent cracking stress, deformation, damage, and fracture of fiber-reinforced CMCs Includes full references and internet links to source material Written by a leading international researcher in the field, High Temperature Mechanical Behavior of Ceramic-Matrix Composites is an invaluable resource for materials scientists, surface chemists, organic chemists, aerospace engineers, and other professionals working with CMCs.
Durability of Ceramic-Matrix Composites presents the latest information on these high-temperature structural materials and their outstanding advantages over more conventional materials, including their high specific strength, high specific modulus, high temperature resistance and good thermal stability. The critical nature of the application of these advanced materials makes it necessary to have a complete understanding of their characterization. This book focuses explicitly on the durability of CMCs and will be extremely valuable for materials scientists and engineers who are dealing with the simulation of durability response and fatigue of ceramic matrix composites. - Provides the latest theoretical and applied research in the field of ceramic matrix composites, particularly as it relates to usage in aerospace propulsion systems - Presents extensive information on the micromechanics of damage evolution, lifetime prediction and durability in ceramic matrix composites - Details parameter studies that are valuable for materials development and lifetime durability studies
This book focuses on mechanical hysteresis behavior in different fiber-reinforced ceramic-matrix composites (CMCs), including 1D minicomposites, 1D unidirectional, 2D cross-ply, 2D plain-woven, 2.5D woven, and 3D needle-punched composites. Ceramic-matrix composites (CMCs) are considered to be the lightweight high-temperature materials for hot-section components in aeroengines with the most potential. To improve the reliability and safety of CMC components during operation, it is necessary to conduct damage and failure mechanism analysis, and to develop models to predict this damage as well as fracture over lifetime - mechanical hysteresis is a key damage behavior in fiber-reinforced CMCs. The appearance of hysteresis is due to a composite’s internal damage mechanisms and modes, such as, matrix cracking, interface debonding, and fiber failure. Micromechanical damage models and constitutive models are developed to predict mechanical hysteresis in different CMCs. Effects of a composite’s constituent properties, stress level, and the damage states of the mechanical hysteresis behavior of CMCs are also discussed. This book also covers damage mechanisms, damage models and micromechanical constitutive models for the mechanical hysteresis of CMCs. This book will be a great resource for students, scholars, material scientists and engineering designers who would like to understand and master the mechanical hysteresis behavior of fiber-reinforced CMCs.
This book focuses on the matrix cracking behavior in ceramic–matrix composites (CMCs), including first matrix cracking behavior, matrix cracking evolution behavior, matrix crack opening and closure behavior considering temperature and oxidation. The micro-damage mechanisms are analyzed, and the micromechanical damage models are developed to characterize the cracking behavior. Experimental matrix cracking behavior of different CMCs at room and elevated temperatures is predicted. The book can help the material scientists and engineering designers to better understand the cracking behavior in CMCs.
Guides researchers and practitioners toward developing highly reliable ceramic-matrix composites The book systematically introduces the thermomechanical fatigue behavior of fiber-reinforced ceramic-matrix composites (CMCs) and environmental barrier coatings, including cyclic loading/unloading tensile behavior, cyclic fatigue behavior, dwell-fatigue behavior, thermomechanical fatigue behavior, and interface degradation behavior. It discusses experimental verification of CMCs and explains how to determine the thermomechanical properties. It also presents damage evolution models, lifetime prediction methods, and interface degradation rules. Thermomechanical Fatigue of Ceramic-Matrix Composites offers chapters covering unidirectional ceramic-matrix composites and cross-ply and 2D woven ceramic-matrix composites. For cyclic fatigue behavior of CMCs, it looks at the effects of fiber volume fraction, fatigue peak stress, fatigue stress ratio, matrix crack spacing, matrix crack mode, and woven structure on fatigue damage evolution. Both the Dwell-fatigue damage evolution and lifetime predictions models are introduced in the next chapter. Experimental comparisons of the cross-ply SiC/MAS composite, 2D SiC/SiC composite, and 2D NextelTM 720/Alumina composite are also included. Remaining sections examine: thermomechanical fatigue hysteresis loops; in-phase thermomechanical fatigue damage; out-of-phase thermomechanical fatigue; interface degradation models; and much more. -Offers unique content dedicated to thermomechanical fatigue behavior of ceramic-matrix composites (CMCs) and environmental barrier coatings -Features comprehensive data tables and experimental verifications -Covers a highly application-oriented subject?CMCs are being increasingly utilized in jet engines, industrial turbines, and exhaust systems Thermomechanical Fatigue of Ceramic-Matrix Composites is an excellent book for developers and users of CMCs, as well as organizations involved in evaluation and characterization of CMCs. It will appeal to materials scientists, construction engineers, process engineers, and mechanical engineers.
Ceramic Matrix Composites: Lifetime and Strength Prediction Under Static and Stochastic Loading focuses on the strain response and lifetime prediction of fiber-reinforced ceramic-matrix composites under stress-rupture loading at intermediate temperatures. Typical damage mechanisms of matrix cracking, interface debonding and oxidation, and fiber's oxidation and fracture are considered in the micromechanical analysis. Effects of composite's constituent properties, peak stress, and testing temperature on the composite's strain response and lifetime are also analyzed in detail. Finally, a comparison of constant and different stochastic stress spectrum on composite's damage evolution and fracture is discussed. This book will be a practical guide for the material researcher and component designer needing to better understand the composite's damage and fracture behavior under stress-rupture loading at intermediate temperatures. - Contains detailed analysis of the stress-rupture behavior of fiber-reinforced ceramic-matrix composites - Includes experimental data on stress-rupture behavior of different CMCs - Presents micromechanical constituent models for characterizing damage and fracture behavior under stress-rupture loading - Provides data on the physical properties of each constituent at various temperatures, along with the composite's response
This book focuses on the vibration behavior of ceramic-matrix composites (CMCs), including (1) vibration natural frequency of intact and damaged CMCs; (2) vibration damping of CMCs considering fibers debonding and fracture; (3) temperature-dependent vibration damping of CMCs; (4) time-dependent vibration damping of CMCs; and (5) cyclic-dependent vibration damping of CMCs. Ceramic-matrix composites (CMCs) possess low material density (i.e., only 1/4 or 1/3 of high-temperature alloy) and high-temperature resistance, which can reduce cooling air and improve structure efficiency. Understanding the failure mechanisms and internal damage evolution represents an important step to ensure reliability and safety of CMCs. Relationships between microstructure, damage mechanisms, vibration natural frequency, and vibration damping of CMCs are established. This book helps the material scientists and engineering designers to understand and master the vibration behavior of CMCs at room and elevated temperatures.
This book presents the relationships between tensile damage and fracture, fatigue hysteresis loops, stress-rupture, fatigue life and fatigue limit stress, and stochastic loading stress. Ceramic-matrix composites (CMCs) possess low material density (i.e., only 1/4 - 1/3 of high-temperature alloy) and high-temperature resistance, which can reduce cooling air and improve structure efficiency. Understanding the failure mechanisms and internal damage evolution represents an important step to ensure reliability and safety of CMCs. This book investigates damage and fracture of fiber-reinforced ceramic-matrix composites (CMCs) subjected to stochastic loading, including: (1) tensile damage and fracture of fiber-reinforced CMCs subjected to stochastic loading; (2) fatigue hysteresis loops of fiber-reinforced CMCs subjected to stochastic loading; (3) stress rupture of fiber-reinforced CMCs with stochastic loading at intermediate temperature; (4) fatigue life prediction of fiber-reinforced CMCs subjected to stochastic overloading stress at elevated temperature; and (5) fatigue limit stress prediction of fiber-reinforced CMCs with stochastic loading. This book helps the material scientists and engineering designers to understand and master the damage and fracture of ceramic-matrix composites under stochastic loading.
This book investigates the time-dependent behavior of fiber-reinforced ceramic-matrix composites (CMCs) at elevated temperatures. The author combines the time-dependent damage mechanisms of interface and fiber oxidation and fracture with the micromechanical approach to establish the relationships between the first matrix cracking stress, matrix multiple cracking evolution, tensile strength, tensile stress-strain curves and tensile fatigue of fiber-reinforced CMCs and time. Then, using damage models of energy balance, the fracture mechanics approach, critical matrix strain energy criterion, Global Load Sharing criterion, and hysteresis loops he determines the first matrix cracking stress, interface debonded length, matrix cracking density, fibers failure probability, tensile strength, tensile stress-strain curves and fatigue hysteresis loops. Lastly, he predicts the time-dependent mechanical behavior of different fiber-reinforced CMCs, i.e., C/SiC and SiC/SiC, using the developed approaches, in order to reduce the failure risk during the operation of aero engines. The book is intended for undergraduate and graduate students who are interested in the mechanical behavior of CMCs, researchers investigating the damage evolution of CMCs at elevated temperatures, and designers responsible for hot-section CMC components in aero engines.
The book "Interfaces of Ceramic-Matrix Composites" demonstrates the definition, function and type of the interface of ceramic-matrix composites and gives comprehensive investigations on the interface design, interface characterization, interface assessment, and interface damage law of both C/SiC and SiC/SiC ceramic-matrix composites subjected to tensile and fatigue loading at different testing conditions. Thereby, it helps material designers and engineers to better design ceramic-matrix composite components for applications.
Ceramic Matrix Composites: Lifetime and Strength Prediction Under Static and Stochastic Loading focuses on the strain response and lifetime prediction of fiber-reinforced ceramic-matrix composites under stress-rupture loading at intermediate temperatures. Typical damage mechanisms of matrix cracking, interface debonding and oxidation, and fiber's oxidation and fracture are considered in the micromechanical analysis. Effects of composite's constituent properties, peak stress, and testing temperature on the composite's strain response and lifetime are also analyzed in detail. Finally, a comparison of constant and different stochastic stress spectrum on composite's damage evolution and fracture is discussed. This book will be a practical guide for the material researcher and component designer needing to better understand the composite's damage and fracture behavior under stress-rupture loading at intermediate temperatures. - Contains detailed analysis of the stress-rupture behavior of fiber-reinforced ceramic-matrix composites - Includes experimental data on stress-rupture behavior of different CMCs - Presents micromechanical constituent models for characterizing damage and fracture behavior under stress-rupture loading - Provides data on the physical properties of each constituent at various temperatures, along with the composite's response
Nonlinear Damage Behavior of Ceramic Matrix Composites help readers [researchers, material scientists and design engineers] gain greater understanding on the damage mechanisms inside CMCs so they can better design components used in aeronautics and astronautics. Key areas addressed in the book include: the nonlinear damage behavior of ceramic-matrix composites, including damage mechanisms and models, nonlinear damage behavior of ceramic-matrix composites under tensile and fatigue loading, strain-rate dependent, stochastic loading dependent, and time dependent nonlinear damage behavior, and the effect of pre-exposure and thermal fatigue on non-linear damage behavior of ceramic-matrix composites. - Provides comprehensive coverage on damage mechanisms and models under tensile and cyclic fatigue loading which ultimately control nonlinear behavior - Covers nonlinear damage analyses of CMC components and experimental observations of damage evolution - Presents extensive knowledge on fracture mechanic principles used in the design of aerospace propulsion systems
This textbook covers the fundamentals of reliability theory and its application for engineering processes, especially for aircraft units and systems. Reliability basis was explained for the best understanding of reliability analysis application for engineering systems in aviation industry. Several approaches for the reliability analysis and their application with examples are presented. It also introduces main trends in the modern reliability theory development. This book will be interested for university students and early-career engineers of aviation industry majors.
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