Virtual Testing and Predictive Modeling (eBook)

For Fatigue and Fracture Mechanics Allowables

Bahram Farahmand (Herausgeber)

eBook Download: PDF

2009 | 2009
XXIII, 407 Seiten
Springer US (Verlag)
978-0-387-95924-5 (ISBN)

Infos

Thematerialsusedinmanufacturingtheaerospace,aircraft,automobile,andnuclear parts have inherent aws that may grow under uctuating load environments during the operational phase of the structural hardware. The design philosophy, material selection, analysis approach, testing, quality control, inspection, and manufacturing are key elements that can contribute to failure prevention and assure a trouble-free structure. To have a robust structure, it must be designed to withstand the envir- mental load throughout its service life, even when the structure has pre-existing aws or when a part of the structure has already failed. If the design philosophy of the structure is based on the fail-safe requirements, or multiple load path design, partial failure of a structural component due to crack propagation is localized and safely contained or arrested. For that reason, proper inspection technique must be scheduled for reusable parts to detect the amount and rate of crack growth, and the possible need for repairing or replacement of the part. An example of a fail-sa- designed structure with crack-arrest feature, common to all aircraft structural parts, is the skin-stiffened design con guration. However, in other cases, the design p- losophy has safe-life or single load path feature, where analysts must demonstrate that parts have adequate life during their service operation and the possibility of catastrophic failure is remote. For example, all pressurized vessels that have single load path feature are classi ed as high-risk parts. During their service operation, these tanks may develop cracks, which will grow gradually in a stable manner.

Inhalt

Acknowledgments 5
Preface 6
Contents 10
Contributors 17
Introduction 19
References 21
Virtual Testing and Its Application in Aerospace Structural Parts 22
1.1 Introduction to the Virtual Testing 23
1.2 Virtual Testing Theory and Fracture Toughness 23
1.3 The Extended Griffith Theory and Fracture Toughness 24
1.4 Extension of FarahmandÌs Theory to Fatigue Crack Growth Rate Data 27
1.5 Application of Virtual Testing in Aerospace Industry: Introduction 33
1.6 Summary and FutureWork 43
Appendix 44
References 49
Tools for Assessing the Damage Tolerance of Primary Structural Components 50
2.1 Introduction 50
2.2 An Equivalent Block Method for Predicting Fatigue Crack Growth 53
2.3 Fatigue Crack Growth under Variable Amplitude Loading 54
2.4 A Virtual Engineering Approach for Predicting the S-N Curves for 7050- T7451 61
2.5 Conclusion 62
Appendix: Formulae for Computing the Crack Opening Stress 64
References 65
Cohesive Technology Applied to the Modeling and Simulation of Fatigue Failure 67
3.1 Introduction 67
3.2 Background 69
3.3 Cohesive Modeling Technique 71
3.4 Simulation Results 81
3.5 Conclusions 89
References 89
Fatigue Damage Map as a Virtual Tool for Fatigue Damage Tolerance 92
4.1 Introduction 92
4.2 The Basic Understanding of Fatigue Damage 93
4.3 Fatigue Damage Map the Basic Rationale - The Navarro-de los Rios Model 104
4.4 Conclusions 120
References 120
Predicting Creep and Creep/Fatigue Crack Initiation and Growth for Virtual Testing and Life Assessment of Components 124
5.1 Introduction 125
5.2 Fracture Mechanics Parameters in Creep and Fatigue 132
5.3 Predictive Models in High-Temperature Fracture Mechanics 135
5.4 Conclusions 150
5.5 Nomenclatures and Abbreviations 152
References 153
Computational Approach Toward Advanced Composite Material Qualification and Structural Certification 156
6.1 Overview 156
6.2 Background 157
6.3 Computational Process for Implementing Building- Block Verification 172
6.4 Establish A- and B-Basis Allowables 182
6.5 Certification by Analysis Example 190
6.6 Summary 201
References 202
Modeling of Multiscale Fatigue Crack Growth: Nano/ Micro and Micro/ Macro Transitions 205
7.1 Introduction 206
7.2 Scale Implications Associated with Size Effects 208
7.3 Form Invariant of Two-Parameter Crack Growth Relation 211
7.4 Dual-Scale Fatigue Crack Growth Rate Models 212
7.5 Micro/Macro Time-Dependent Physical Parameters 216
7.6 Nano/Micro Time-Dependent Physical Parameters 222
7.7 Fatigue Crack Growth and Velocity Data 226
7.8 Validation of Nano/Micro/Macro Fatigue Crack Growth Behavior 230
7.9 Implication of Multiscaling and Future Considerations 232
References 235
Multiscale Modeling of Nanocomposite Materials 238
8.1 Introduction 238
8.2 Computational Modeling Tools 240
8.3 Equivalent-Continuum Models 241
8.4 Equivalent-Continuum Modeling Strategies 250
8.5 Examples 253
8.6 Summary 259
References 260
Predictive Modeling 263
9.1 Introduction 264
9.2 Nanocomposites 267
9.3 Multiscale Modeling 282
9.4 Continuum Methods 283
9.5 Materials Engineering Simulation Across Multi-Length and Time Scales 285
9.6 Extension of Atomistic Ensemble Methods 291
9.7 Future Improvement 294
9.8 Summary 295
References 297
Multiscale Approach to Predicting the Mechanical Behavior of Polymeric Melts 306
10.1 Introduction 306
10.2 Single and Multiscale Modeling Methods: Limitations and Tradeoffs 308
10.3 Two Information-Passing Examples 313
References 332
Prediction of Damage Propagation and Failure of Composite Structures ( Without Testing) 335
11.1 Introduction 335
11.2 Basics of Progressive Damage Modelling methodology 337
11.3 Buckling and Damage Interaction of Open-Hole Composite Plates by PDM 348
11.4 Implementation of PDM in Composite Bolted Joints 353
11.5 Implementation of PDM in Composite Bonded Repairs 359
11.6 Multi-Scale Modeling of Tensile Behavior of Carbon Nanotube- Reinforced Composites 364
11.7 Conclusions 366
References 367
Functional Nanostructured Polymer- Metal Interfaces 371
12.1 Introduction 371
12.2 Oblique-Angle Polymerization 372
12.3 Metallization of Nanostructured Polymers 375
12.4 Conclusions 380
References 382
Advanced Experimental Techniques for Multiscale Modeling of Materials 384
13.1 Atomic Force Microscopy (AFM) 385
13.2 X-Ray Ultra-Microscopy 395
13.3 In Situ Micro-Electro-Mechanical-Systems (MEMS) Introduction 401
13.4 Concluding Remarks 408
References 409
Index 412

Produkt-Details

• Erscheint lt. Verlag: 29.6.2009
• Zusatzinfo: XXIII, 407 p.
• Verlagsort: New York
• Sprache: englisch
• Themenwelt: Mathematik / Informatik ► Mathematik ► Statistik
• Themenwelt: Mathematik / Informatik ► Mathematik ► Wahrscheinlichkeit / Kombinatorik
• Themenwelt: Naturwissenschaften ► Physik / Astronomie ► Mechanik
• Themenwelt: Technik ► Fahrzeugbau / Schiffbau
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: composite • Composite material • Continuum Mechanics • damage • damage tolerant assessment • Deformation • energy release rate concept • fatigue • Fatigue crack growth • Fracture • fracture mechanics • material allowable • Materials • mechanical and fracture properties • Mechanics • Metal • micro-mechanics approach • Modeling • modeling and simulation of fatigue failure • Simulation • S-N curve generation • Structures • Testing
• ISBN-10: 0-387-95924-6 / 0387959246
• ISBN-13: 978-0-387-95924-5 / 9780387959245