Table of Contents
Preface xiii
Acknowledgments xv
1 Introduction 1
1.1 Tensile Behavior of CMCs at Elevated Temperature 2
1.2 Fatigue Behavior of CMCs at Elevated Temperature 6
1.3 Stress Rupture Behavior of CMCs at Elevated Temperature 7
1.4 Vibration Behavior of CMCs at Elevated Temperature 9
1.5 Conclusion 10
References 10
2 First Matrix Cracking of Ceramic-Matrix Composites at Elevated Temperature 19
2.1 Introduction 19
2.2 Temperature-Dependent Matrix Cracking Stress of C/SiC Composites 20
2.2.1 Theoretical Models 20
2.2.2 Results and Discussion 21
2.2.2.1 Temperature-Dependent Matrix Cracking Stress of C/SiC Composite for Different Fiber Volumes 23
2.2.2.2 Temperature-Dependent Matrix Cracking Stress of C/SiC Composite for Different Interface Shear Stress 24
2.2.2.3 Temperature-Dependent Matrix Cracking Stress of C/SiC Composite for Different Fiber/Matrix Interface Frictional Coefficients 25
2.2.2.4 Temperature-Dependent Matrix Cracking Stress of C/SiC Composite for Different Interface Debonding Energies 26
2.2.2.5 Effect of Matrix Fracture Energy on Temperature-Dependent Matrix Cracking Stress of C/SiC Composite 27
2.2.3 Experimental Comparisons 28
2.3 Temperature-Dependent Matrix Cracking Stress of SiC/SiC Composite 29
2.3.1 Results and Discussion 30
2.3.1.1 Temperature-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Fiber Volumes 30
2.3.1.2 Temperature-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Interface Shear Stress 30
2.3.1.3 Temperature-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Interface Frictional Coefficients 33
2.3.1.4 Temperature-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Interface Debonding Energies 34
2.3.1.5 Temperature-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Matrix Fracture Energies 34
2.3.2 Experimental Comparisons 36
2.4 Time-Dependent Matrix Cracking Stress of C/SiC Composites 39
2.4.1 Theoretical Models 39
2.4.2 Results and Discussion 41
2.4.2.1 Time-Dependent Matrix Cracking Stress of C/SiC Composite for Different Fiber Volumes 42
2.4.2.2 Time-Dependent Matrix Cracking Stress of C/SiC Composite for Different Interface Shear Stress 42
2.4.2.3 Time-Dependent Matrix Cracking Stress of C/SiC Composite for Different Interface Frictional Coefficients 50
2.4.2.4 Time-Dependent Matrix Cracking Stress of C/SiC Composite for Different Interface Debonding Energies 53
2.4.2.5 Time-Dependent Matrix Cracking Stress of C/SiC Composite for Different Matrix Fracture Energies 56
2.4.3 Experimental Comparisons 59
2.5 Time-Dependent Matrix Cracking Stress of Si/SiC Composites 59
2.5.1 Results and Discussion 59
2.5.1.1 Time-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Fiber Volumes 60
2.5.1.2 Time-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Interface Shear Stress 62
2.5.1.3 Time-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Interface Debonding Energies 66
2.5.1.4 Time-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Matrix Fracture Energies 68
2.5.2 Experimental Comparisons 68
2.6 Conclusion 71
References 71
3 Matrix Multiple Cracking Evolution of Fiber-Reinforced Ceramic-Matrix Composites at Elevated Temperature 75
3.1 Introduction 75
3.2 Temperature-Dependent Matrix Multiple Cracking Evolution of C/SiC Composites 76
3.2.1 Theoretical Models 77
3.2.1.1 Temperature-Dependent Stress Analysis 77
3.2.1.2 Temperature-Dependent Interface Debonding 78
3.2.1.3 Temperature-Dependent Matrix Multiple Cracking 79
3.2.2 Results and Discussion 80
3.2.2.1 Temperature-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Interface Shear Stress 82
3.2.2.2 Temperature-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Interface Debonding Energies 84
3.2.2.3 Temperature-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Matrix Fracture Energies 85
3.2.3 Experimental Comparisons 88
3.3 Temperature-Dependent Matrix Multiple Cracking Evolution of SiC/SiC Composites 89
3.3.1 Results and Discussion 90
3.3.1.1 Temperature-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Fiber Volumes 90
3.3.1.2 Temperature-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Interface Shear Stress 92
3.3.1.3 Temperature-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Interface Frictional Coefficients 93
3.3.1.4 Temperature-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Interface Debonding Energies 95
3.3.1.5 Temperature-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Matrix Fracture Energies 98
3.3.2 Experimental Comparisons 100
3.4 Time-Dependent Matrix Multiple Cracking Evolution of C/SiC Composites 101
3.4.1 Theoretical Models 102
3.4.1.1 Time-Dependent Stress Analysis 102
3.4.1.2 Time-Dependent Interface Debonding 103
3.4.1.3 Time-Dependent Matrix Multiple Cracking 105
3.4.2 Results and Discussion 106
3.4.2.1 Time-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Interface Shear Stress 106
3.4.2.2 Time-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Interface Frictional Coefficients 108
3.4.2.3 Time-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Interface Debonding Energies 111
3.4.2.4 Time-Dependent Matrix Multiple Cracking of C/SiC Composite for Different Matrix Fracture Energies 113
3.4.3 Experimental Comparisons 114
3.5 Time-Dependent Matrix Multiple Cracking Evolution of SiC/SiC Composites 116
3.5.1 Results and Discussion 117
3.5.1.1 Time-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Fiber Volumes 117
3.5.1.2 Time-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Interface Shear Stress 120
3.5.1.3 Time-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Interface Frictional Coefficients 127
3.5.1.4 Time-Dependent Matrix Multiple Cracking of SiC/SiC Composite for Different Interface Debonding Energies 130
3.5.1.5 Time-Dependent Matrix Cracking Stress of SiC/SiC Composite for Different Matrix Fracture Energies 133
3.5.2 Experimental Comparisons 136
3.5.2.1 Unidirectional SiC/SiC Composite 136
3.5.2.2 SiC/SiC Minicomposite 139
3.6 Conclusion 139
References 140
4 Time-Dependent Tensile Behavior of Ceramic-Matrix Composites 145
4.1 Introduction 145
4.2 Theoretical Analysis 148
4.3 Results and Discussion 149
4.3.1 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Fiber Volumes 149
4.3.2 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Fiber Radii 149
4.3.3 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Matrix Weibull Moduli 152
4.3.4 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Matrix Cracking Characteristic Strengths 152
4.3.5 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Matrix Cracking Saturation Spacings 155
4.3.6 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Interface Shear Stress 155
4.3.7 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Interface Debonding Energies 155
4.3.8 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Fiber Strengths 159
4.3.9 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Fiber Weibull Moduli 160
4.3.10 Time-Dependent Tensile Behavior of SiC/SiC Composite for Different Oxidation Durations 160
4.4 Experimental Comparisons 161
4.4.1 Time-Dependent Tensile Behavior of SiC/SiC Composite 161
4.4.2 Time-Dependent Tensile Behavior of C/SiC Composite 173
4.5 Conclusion 179
References 181
5 Fatigue Behavior of Ceramic-Matrix Composites at Elevated Temperature 187
5.1 Introduction 187
5.2 Theoretical Analysis 189
5.3 Experimental Comparisons 191
5.3.1 2.5DWoven Hi-NicalonTM SiC/[Si-B-C] at 600 ∘C in Air Atmosphere 191
5.3.2 2.5DWoven Hi-NicalonTM SiC/[Si-B-C] at 1200 ∘C in Air Atmosphere 193
5.3.3 2DWoven Self-Healing Hi-NicalonTM SiC/[SiC-B4C] at 1200 ∘C in Air and in Steam Atmospheres 199
5.3.4 Discussion 203
5.4 Conclusion 206
References 206
6 Stress Rupture of Ceramic-Matrix Composites at Elevated Temperature 211
6.1 Introduction 211
6.2 Stress Rupture of Ceramic-Matrix Composites Under Constant Stress at Intermediate Temperature 213
6.2.1 Theoretical Models 214
6.2.2 Results and Discussion 215
6.2.2.1 Stress Rupture of SiC/SiC Composite for Different Fiber Volumes 215
6.2.2.2 Stress Rupture of SiC/SiC Composite for Different Peak Stress Levels 218
6.2.2.3 Stress Rupture of SiC/SiC Composite for Different Saturation Spaces Between Matrix Cracking 221
6.2.2.4 Stress Rupture of SiC/SiC Composite for Different Interface Shear Stress 221
6.2.2.5 Stress Rupture of SiC/SiC Composite for Different Fiber Weibull Modulus 227
6.2.2.6 Stress Rupture of SiC/SiC Composite for Different Environmental Temperatures 229
6.2.3 Experimental Comparisons 230
6.3 Stress Rupture of Ceramic-Matrix Composites Under Stochastic Loading Stress and Time at Intermediate Temperature 234
6.3.1 Results and Discussion 236
6.3.1.1 Stress Rupture of SiC/SiC Composite Under Stochastic Loading for Different Stochastic Stress Levels 236
6.3.1.2 Stress Rupture of SiC/SiC Composite Under Stochastic Loading for Different Stochastic Loading Time Intervals 240
6.3.1.3 Stress Rupture of SiC/SiC Composite Under Stochastic Loading for Different Fiber Volumes 247
6.3.1.4 Stress Rupture of SiC/SiC Composite Under Stochastic Loading for Different Matrix Crack Spacings 251
6.3.1.5 Stress Rupture of SiC/SiC Composite Under Stochastic Loading for Different Interface Shear Stress 253
6.3.1.6 Stress Rupture of SiC/SiC Composite Under Stochastic Loading for Different Environmental Temperatures 261
6.3.2 Experimental Comparisons 264
6.3.2.1 𝜎= 80 MPa and 𝜎s = 90 MPa with Δt = 7.2, 10.8, and 14.4 ks 267
6.3.2.2 𝜎= 100 MPa and 𝜎s = 110 MPa with Δt = 7.2 ks 267
6.3.2.3 𝜎= 120 MPa and 𝜎s = 130 and 140 MPa with Δt = 7.2 ks 271
6.3.2.4 Discussion 271
6.4 Stress Rupture of Ceramic-Matrix Composites Under Multiple Load Sequence at Intermediate Temperature 274
6.4.1 Results and Discussion 274
6.4.1.1 Stress Rupture of SiC/SiC Composite Under Multiple Loading Sequence for Different Fiber Volumes 275
6.4.1.2 Stress Rupture of SiC/SiC Composite Under Multiple Loading Sequence for Different Matrix Crack Spacings 280
6.4.1.3 Stress Rupture of SiC/SiC Composite Under Multiple Loading Sequence for Different Interface Shear Stress 285
6.4.1.4 Stress Rupture of SiC/SiC Composite Under Multiple Loading Sequence for Different Environment Temperatures 292
6.4.2 Experimental Comparisons 295
6.5 Conclusion 302
References 302
7 Vibration Damping of Ceramic-Matrix Composites at Elevated Temperature 307
7.1 Introduction 307
7.2 Temperature-Dependent Vibration Damping of CMCs 308
7.2.1 Theoretical Models 308
7.2.2 Results and Discussion 310
7.2.2.1 Effect of Fiber Volume on Temperature-Dependent Vibration Damping of SiC/SiC Composite 310
7.2.2.2 Effect of Matrix Crack Spacing on Temperature-Dependent Vibration Damping of SiC/SiC Composite 314
7.2.2.3 Effect of Interface Debonding Energy on Temperature-Dependent Vibration Damping of SiC/SiC Composite 317
7.2.2.4 Effect of Steady-State Interface Shear Stress on Temperature-Dependent Vibration Damping of SiC/SiC Composite 321
7.2.2.5 Effect of Interface Frictional Coefficient on Temperature-Dependent Vibration Damping of SiC/SiC Composite 325
7.2.3 Experimental Comparisons 329
7.3 Time-Dependent Vibration Damping of CMCs 329
7.3.1 Theoretical Models 329
7.3.2 Results and Discussion 331
7.3.2.1 Effect of Fiber Volume on Time-Dependent Vibration Damping of C/SiC Composite 331
7.3.2.2 Effect of Vibration Stress on Time-Dependent Vibration Damping of C/SiC Composite 334
7.3.2.3 Effect of Matrix Crack Spacing on Time-Dependent Vibration Damping of C/SiC Composite 337
7.3.2.4 Effect of Interface Shear Stress on Time-Dependent Vibration Damping of C/SiC Composite 340
7.3.2.5 Effect of Temperature on Time-Dependent Vibration Damping of C/SiC Composite 343
7.3.3 Experimental Comparisons 343
7.3.3.1 t =2 hours at T = 700, 1000, and 1300 ∘C 346
7.3.3.2 t = 5 hours at T = 700, 1000, and 1300 ∘C 346
7.3.3.3 t = 10 hours at T = 700, 1000, and 1300 ∘C 351
7.3.3.4 Discussion 354
7.4 Conclusion 356
References 356