Thermomechanical Fatigue of Ceramic-Matrix Composites

Longbiao Li, PhD, is Lecturer in the College of Civil Aviation at Nanjing University of Aeronautics and Astronautics in China, where he received his PhD. His research focuses on the thermomechanical fatigue of high-temperature ceramic-matrix composites. He has published more than 100 journal articles.

• 1 Cyclic Loading/Unloading Tensile Fatigue of Ceramic-Matrix Composites 11.1 Introduction 11.2 Unidirectional Ceramic-Matrix Composites 21.2.1 Materials and Experimental Procedures 31.2.1.1 C/SiC Composite 31.2.1.2 C/Si3N4 and SiC/Si3N4 Composites 31.2.1.3 SiC/CAS Composite 41.2.2 Theoretical Analysis 41.2.2.1 Stress Analysis 41.2.2.2 Matrix Cracking 61.2.2.3 Interface Debonding 71.2.2.4 Fiber Failure 81.2.2.5 Hysteresis Theories 91.2.3 Results and Discussion 131.2.3.1 Effect of Fiber Volume Fraction on Fatigue Hysteresis Loops and Fatigue Hysteresis-Based Damage Parameters 131.2.3.2 Effect of Matrix Cracking Density on Fatigue Hysteresis Loops and Fatigue Hysteresis-Based Damage Parameters 151.2.3.3 Effect of Fiber/Matrix Interface Shear Stress on Fatigue Hysteresis Loops and Fatigue Hysteresis-Based Damage Parameters 161.2.3.4 Effect of Fiber/Matrix Interface Debonded Energy on Fatigue Hysteresis Loops and Fatigue Hysteresis-Based Damage Parameters 201.2.3.5 Effect of Fiber Failure on Fatigue Hysteresis Loops and Fatigue Hysteresis-Based Damage Parameters 221.2.4 Experimental Comparisons 241.2.4.1 C/SiC Composite 241.2.4.2 C/Si3N4 Composite 301.2.4.3 SiC/Si3N4 Composite 331.2.4.4 SiC/CAS Composite 381.3 Cross-Ply and 2D Woven Ceramic-Matrix Composites 431.3.1 Materials and Experimental Procedures 471.3.1.1 C/SiC Composite 471.3.1.2 SiC/SiC Composite 481.3.2 Theoretical Analysis 491.3.2.1 Stress Analysis 491.3.2.2 Transverse and Matrix Cracking 581.3.2.3 Interface Debonding 601.3.2.4 Hysteresis Theories 621.3.3 Results and Discussions 751.3.3.1 Effect of Fiber Volume Fraction on the Interface Sliding and Fatigue Hysteresis Loops 751.3.3.2 Effect of Fatigue Peak Stress on the Interface Sliding and Fatigue Hysteresis Loops 771.3.3.3 Effect of Matrix Crack Spacing on the Interface Sliding and Fatigue Hysteresis Loops 791.3.3.4 Effect of Interface Properties on the Interface Sliding and Fatigue Hysteresis Loops 811.3.3.5 Effect of Matrix Racking Mode Proportion on Interface Sliding and Fatigue Hysteresis Loops 851.3.4 Experimental Comparisons 871.3.4.1 Cross-Ply C/SiC Composite 871.3.4.2 2D SiC/SiC Composite 941.4 2.5D and 3D Ceramic-Matrix Composites 1031.4.1 Materials and Experimental Procedures 1041.4.1.1 2.5D C/SiC Composite 1041.4.1.2 3D Braided C/SiC Composite 1041.4.1.3 3D Needled C/SiC Composite 1051.4.2 HysteresisTheories 1051.4.2.1 Interface Slip Case 1 1051.4.2.2 Interface Slip Case 2 1061.4.2.3 Interface Slip Case 3 1071.4.2.4 Hysteresis Loops 1071.4.3 Experimental Comparisons 1081.4.3.1 2.5D C/SiC Composite 1081.4.3.2 3D Braided C/SiC Composite 1101.4.3.3 3D Needled C/SiC Composite 1121.5 Conclusions 112References 1122 Cyclic Fatigue Behaviors of Ceramic-Matrix Composites 1172.1 Introduction 1172.2 Materials and Experimental Procedures 1172.2.1 Unidirectional C/SiC Composite 1172.2.2 Cross-Ply C/SiC Composite 1182.2.3 2D SiC/SiC Composite at 1000°C 1192.2.4 2D SiC/SiC Composite at 1200°C 1202.2.5 2D SiC/SiC Composite at 1300°C 1202.2.6 3D SiC/SiC Composite at 1300°C 1212.3 Hysteresis-Based Damage Parameters 1212.4 Results and Discussions 1222.4.1 Effects of Fiber Volume Fraction on Fatigue Damage Evolution 1232.4.2 Effects of Fatigue Peak Stress on Fatigue Damage Evolution 1252.4.3 Effects of Fatigue Stress Ratio on Fatigue Damage Evolution 1272.4.4 Effects of Matrix Crack Spacing on Fatigue Damage Evolution 1282.4.5 Effects of Matrix Crack Mode on Fatigue Damage Evolution 1292.4.6 Effects of Woven Structure on Fatigue Damage Evolution 1332.5 Experimental Comparisons 1352.5.1 Unidirectional CMCs 1352.5.1.1 SiC/CAS Composite at Room Temperature 1352.5.1.2 SiC/CAS-II Composite at Room Temperature 1372.5.1.3 SiC/1723 Composite at Room Temperature 1402.5.1.4 C/SiC Composite at Room Temperature 1432.5.1.5 C/SiC Composite at Elevated Temperature 1472.5.2 Cross-Ply CMCs 1522.5.2.1 SiC/CAS Composite at Room Temperature 1522.5.2.2 C/SiC Composite at Room Temperature 1552.5.2.3 C/SiC Composite at 800°C in Air Atmosphere 1562.5.2.4 SiC/MAS-L Composite at 800 and 1000°C in Inert Atmosphere 1582.5.3 2D CMCs 1582.5.3.1 SiC/SiC Composite at 600, 800, and 1000°C in Inert Atmosphere 1582.5.3.2 SiC/SiC Composite at 1000∘C in Air and in Steam Atmospheres 1642.5.3.3 SiC/SiC Composite at 1200∘C in Air and in Steam Atmospheres 1912.5.3.4 SiC/SiC Composite at 1300∘C in Air Atmosphere 2092.5.4 3D Braided CMCs 2262.6 Discussions 2292.6.1 Cyclic Fatigue at Room Temperature 2292.6.2 Cyclic Fatigue at Elevated Temperature 2332.6.3 Comparison Analysis 2382.7 Conclusions 245References 2463 Dwell-Fatigue Behavior of Ceramic-Matrix Composites 2493.1 Introduction 2493.2 Theoretical Analysis 2513.2.1 Dwell-Fatigue Damage Evolution Model 2533.2.2 Dwell-Fatigue Lifetime Prediction Model 2563.3 Results and Discussions 2583.3.1 Effects of Hold Time on Dwell Fatigue Damage Evolution 2583.3.2 Effects of Stress Level on Dwell Fatigue Damage Evolution 2633.3.3 Effects of Matrix Crack Spacing on Dwell Fatigue Damage Evolution 2683.3.4 Effects of Fiber Volume Fraction on Dwell Fatigue Damage Evolution 2723.3.5 Effects of Oxidation Temperature on Dwell Fatigue Damage Evolution 2763.4 Experimental Comparisons 2803.4.1 Cross-Ply SiC/MAS Composite 2803.4.1.1 566∘C in Air Atmosphere 2803.4.1.2 1093∘C in AirAtmosphere 2883.4.1.3 Comparison Analysis 2963.4.2 2D SiC/SiC Composite 3013.4.3 2D Nextel 720/Alumina Composite 3033.5 Conclusions 304References 3054 Thermomechanical Fatigue Behaviors of Ceramic-Matrix Composites 3094.1 Introduction 3094.2 Theoretical Analysis 3104.2.1 Thermomechanical Stress Analysis 3104.2.2 Thermomechanical Damage Parameters 3124.3 Thermomechanical Fatigue Hysteresis Loops 3134.3.1 Results and Discussions 3134.3.1.1 Effects of Fiber Volume Fraction on the Thermomechanical Fatigue Hysteresis Loops and Fiber/Matrix Interface Sliding 3134.3.1.2 Effects of Fatigue Peak Stress on the Thermomechanical Fatigue Hysteresis Loops and Fiber/Matrix Interface Sliding 3174.3.1.3 Effects of Matrix Crack Spacing on the Thermomechanical Fatigue Hysteresis Loops and Fiber/Matrix Interface Sliding 3214.3.1.4 Effects of Fiber/Matrix Interface Frictional Coefficient on the Thermomechanical Fatigue Hysteresis Loops and Fiber/Matrix Interface Sliding 3254.3.1.5 Effects of Interface Debonded Energy on the Thermomechanical Fatigue Hysteresis Loops and Fiber/Matrix Interface Sliding 3284.3.1.6 Effects of Thermal Cyclic Temperature Range on the Thermomechanical Fatigue Hysteresis Loops and Fiber/Matrix Interface Sliding 3324.3.2 Experimental Comparisons 3364.3.2.1 Isothermal Fatigue Hysteresis Loops 3364.3.2.2 In-Phase Thermomechanical Fatigue Hysteresis Loops 3414.3.2.3 Out-of-phase Thermomechanical Fatigue Hysteresis Loops 3444.4 In-phase Thermomechanical Fatigue Damage 3454.4.1 Results and Discussions 3474.4.1.1 Effects of Fiber Volume Fraction on In-phase Thermomechanical Fatigue Damage Evolution 3484.4.1.2 Effects of Fatigue Peak Stress on In-phase Thermomechanical Fatigue Damage Evolution 3544.4.1.3 Effects of Matrix Stochastic Cracking on In-phase Thermomechanical Fatigue Damage Evolution 3574.4.1.4 Effects of Interface Properties on In-phase Thermomechanical Fatigue Damage Evolution 3614.4.1.5 Effects of Thermal Cyclic Temperature Range on In-phase Thermomechanical Fatigue Damage Evolution 3654.4.1.6 Comparisons Between In-phase Thermomechanical and Isothermal Fatigue Loading 3684.4.2 Experimental Comparisons 3704.4.2.1 Thermomechanical Fatigue Loading 3714.4.2.2 Isothermal Fatigue Loading 3724.5 Out-of-phase Thermomechanical Fatigue 3734.5.1 Results and Discussions 3744.5.1.1 Effects of Fiber Volume Fraction on Out-of-phase Thermomechanical Fatigue Damage Evolution 3744.5.1.2 Effects of Fatigue Peak Stress on Out-of-phase Thermomechanical Fatigue Damage Evolution 3794.5.1.3 Effects of Matrix Crack Spacing on Out-of-phase Thermomechanical Fatigue Damage Evolution 3834.5.1.4 Effects of Interface Frictional Coefficient on Out-of-phase Thermomechanical Fatigue Damage Evolution 3864.5.1.5 Effects of Thermal Cyclic Temperature Range Out-of-phase Thermomechanical Fatigue Damage Evolution 3904.5.1.6 Comparisons Between In-phase/Out-of-phase Thermomechanical Fatigue and Isothermal Fatigue Loading 3934.5.2 Experimental Comparisons 3974.5.2.1 Out-of-phase Thermomechanical Fatigue Loading at the Temperature Range from 566 to 1093∘C 3974.5.2.2 Isothermal Fatigue Loading at 566∘C 3994.5.2.3 Isothermal Fatigue Loading at 1093∘C 4014.6 Thermomechanical Fatigue with Different Phase Angles 4034.6.1 Results and Discussions 4034.6.1.1 Effects of Fiber Volume Fraction on Thermomechanical Fatigue Damage Evolution 4084.6.1.2 Effects of Fatigue Peak Stress on Thermomechanical Fatigue Damage Evolution 4164.6.1.3 Effects of Matrix Crack Spacing on Thermomechanical Fatigue Damage Evolution 4264.6.2 Experimental Comparisons 4324.6.2.1 In-phase Thermomechanical Fatigue 4334.6.2.2 Out-of-phase Thermomechanical Fatigue 4334.7 Conclusions 434References 4345 Interface Degradation of Ceramic-Matrix Composites Under Thermomechanical Fatigue Loading 4375.1 Introduction 4375.2 Interface Degradation Models 4385.2.1 Interface Slip Case 1 4385.2.2 Interface Slip Case 2 4395.2.3 Interface Slip Case 3 4395.2.4 Interface Slip Case 4 4405.2.5 Hysteresis Loops and Hysteresis-Based Damage Parameters 4415.3 Experimental Comparisons 4455.3.1 Unidirectional C/SiC Composite 4455.3.1.1 Room Temperature 4455.3.1.2 Elevated Temperature 4515.3.1.3 Comparison Analysis 4565.3.2 Unidirectional SiC/Si3N4 Composite 4575.3.2.1 Room Temperature 4575.3.2.2 Elevated Temperature 4615.3.2.3 Comparison Analysis 4675.3.3 2D SiC/SiC Composite 4685.3.3.1 Room Temperature 4685.3.3.2 Elevated Temperature 4705.3.3.3 Comparison Analysis 4725.4 Conclusions 473References 474Index 475