Ageing of composites

Cover Page
......Page 1
Title Page
......Page 2
Ageing of composites......Page 4
Contents......Page 6
Contributor contact details......Page 13
Introduction......Page 18
Part I: Ageing of composites – processes and modelling......Page 23
1.1 Introduction......Page 24
1.2 Background......Page 28
1.2.1 Accelerated ageing......Page 30
1.3 Viscoelasticity......Page 31
1.3.1 Superposition......Page 32
1.3.2 Linearity......Page 33
1.3.3 Time–temperature superposition......Page 34
1.4 Ageing and effective time......Page 36
1.4.1 Time–ageing time superposition......Page 37
1.4.2 Time–temperature–ageing superposition......Page 40
1.5 Development of an ageing study......Page 43
1.5.1 The influence of geometry......Page 44
1.5.2 Thermo-oxidative degradation......Page 45
1.5.3 Thermal degradation......Page 46
1.6 Summary......Page 49
1.7 References......Page 50
2.1.1 Fibre-reinforced glasses and glass-ceramics......Page 55
2.1.2 Macromechanical behaviour......Page 56
2.1.3 Interfacial micromechanics......Page 60
2.1.4 Carbon and boron nitride interphases......Page 61
2.1.5 Applications of advanced ceramic matrix composites......Page 62
2.3 Fast-fracture behaviour......Page 63
2.4 Long-term environmental ageing behaviour......Page 64
2.4.1 High-temperature stability......Page 65
2.4.2 Intermediate temperature degradation......Page 68
2.4.3 Low-temperature degradation......Page 69
2.5.1 Intermediate- and low-temperature degradation......Page 72
2.5.2 High-temperature sealing......Page 75
2.7 Oxidation behaviour under applied stress......Page 78
2.7.1 Static fatigue......Page 79
2.7.2 Cyclic fatigue......Page 80
2.7.3 Creep......Page 81
2.9 Composite protection methods......Page 83
2.10 Conclusions and future trends......Page 84
2.11 References......Page 85
3.1.2 Focus and limitations......Page 92
3.2.1 Introduction......Page 93
3.2.3 Identification of external sources influencing the chemical attack......Page 94
3.3.1 Single fibres in a pore solution......Page 95
3.3.2 Fibres in a matrix block......Page 96
3.4.1 Literature overview......Page 97
3.4.2 Direct chemical attack of fibres: modelling the evolution with time......Page 101
3.4.3 Modelling the influence of temperature......Page 102
3.4.4 Modelling the influence of humidity......Page 105
3.4.5 Calibration example and discussion......Page 106
3.5 Interface effects......Page 111
3.6 Composite loading effects......Page 112
3.7 In situ degradation of composites due to chemical attack......Page 113
3.8 Conclusions......Page 117
3.10 References......Page 118
4.1 Introduction......Page 121
4.2.1 Experimental evidence for stress corrosion cracking processes in glass fibre reinforced polymer laminates......Page 122
4.2.2 Basic mechanisms for the interaction between environment and fatigue damage......Page 125
4.3.1 Physical and mechanical processes involved in the delayed failure of glasses......Page 128
4.3.2 Determination of subcritical crack propagation velocities in glass fibres......Page 131
Lifetime of a single fibre......Page 134
Delayed failure of a statistical population of fibres under stress corrosion cracking conditions......Page 135
4.4.1 Micromechanical analysis of delayed fibre failure within water-aged glass fibre reinforced polymers......Page 136
4.4.2 Lifetime prediction for unidirectional glass/epoxy composite beams under stress corrosion cracking conditions......Page 139
Static fatigue behaviour (R = 1)......Page 141
Cyclic fatigue behaviour (R ≠ 1)......Page 143
4.5 Concluding remarks and future trends......Page 145
4.6 References......Page 147
5.1.1 Importance of thermo-oxidative ageing in composites development......Page 151
5.1.2 Application areas and relevance to matrix chemistry......Page 152
5.1.3 Key factors in characterization......Page 154
5.1.4 Test methodologies......Page 155
5.3 Initial studies – Kerr and Haskins......Page 157
5.4 Overview of other studies......Page 159
5.4.1 PMR-15......Page 160
5.4.2 Other materials......Page 163
5.4.3 Gravimetric methods......Page 165
5.4.4 Effects of pressure......Page 167
5.4.5 Modeling......Page 169
5.5.1 General observations......Page 171
Modeling and characterization......Page 172
Materials development......Page 173
5.6 Conclusions and recommendations......Page 174
5.7 References......Page 175
6.1 Introduction......Page 181
6.2.1 Theory......Page 182
6.2.2 Instrumentation and practice......Page 187
6.2.3 Further reading on Fourier transform infrared photoacoustic spectroscopy......Page 189
6.3.1 Thermal and photochemical ageing......Page 191
6.3.2 Hydrolytic degradation......Page 198
6.5 Acknowledgements......Page 201
6.6 References......Page 203
7.1 Introduction......Page 207
7.2.1 Exponential model......Page 208
7.2.2 Power law model......Page 211
7.2.3 Effective compliancecreep model......Page 213
7.3.1 Effective time model......Page 221
7.3.2 Long-term creep prediction......Page 223
7.4 Temperature and moisture effects......Page 224
7.6 References......Page 225
8.2 Silicon carbide composites......Page 227
8.3 Ageing kinetics......Page 229
8.4 Microstructural change......Page 232
8.4.1 Effect of grain size and porosity......Page 233
8.4.2 Effect of matrix composition......Page 234
8.5 Effect of volume fraction and size of silicon carbide reinforcement......Page 235
8.6.1 Tensile properties......Page 238
8.6.2 Wear......Page 239
8.6.3 Corrosion......Page 240
8.7 References......Page 241
9.1 Introduction......Page 245
9.2 Definition of environmental conditions and important variables......Page 247
9.3 Degradation mechanisms and processes......Page 248
9.3.1 Time-dependent mechanical behaviour......Page 249
9.3.3 Physical ageing......Page 251
9.3.4 Hygrothermal effects......Page 252
9.3.5 Thermo-oxidative degradation......Page 253
9.4 Modelling time-dependent mechanical behaviour......Page 254
9.4.2 Time–temperature superposition for a thermorheologically simple material......Page 255
9.4.3 Effective or material time concept......Page 256
9.4.4 Non-linear viscoelastic polymers......Page 257
9.4.5 Viscoelastic–viscoplastic behaviour......Page 258
9.4.6 Application to composite materials......Page 259
9.5 Modelling mechanical degradation......Page 261
9.6 Modelling physical ageing......Page 262
9.6.1 Application to composites......Page 266
9.7 Modelling hygrothermal effects......Page 267
9.7.1 Application to composites......Page 272
9.8 Modelling chemical ageing......Page 275
9.9 Methodology for accelerated testing based on the modelling approach......Page 277
9.10 Accelerated long-time mechanical behaviour......Page 278
9.10.1 Long-time viscoelastic behaviour of polymer matrix composites......Page 279
Creep rupture......Page 282
Static versus creep strength......Page 283
Fatigue......Page 284
Effect of combined states of loading and degradation factors......Page 288
9.11 Accelerated mechanical degradation......Page 291
9.13 Accelerated hygrothermal degradation......Page 293
9.14 Accelerated thermal degradation and oxidation......Page 294
9.15 Validation of acceleration procedure by comparison with real-time data......Page 296
9.17 References......Page 297
Part II: Ageing of composites in transport applications......Page 303
10.1.1 The use of composites in the rail industry......Page 304
10.1.2 The importance of research into ageing of composites for the rail industry......Page 305
10.1.3 A brief history of environmental ageing research on composites......Page 307
10.1.4 Objectives of the chapter......Page 308
10.2.2 Thermal cycling......Page 309
10.3 Environmental test methods and evaluation procedures for ageing of composites......Page 310
Accelerated ageing tests......Page 311
10.3.2 Evaluation of the degration of composite properties through natural and accelerated ageing tests......Page 312
The evaluation of ageing of composites through accelerated ageing tests......Page 313
The evaluation of ageing of composites through natural ageing tests......Page 315
10.3.3 The degradation equation for stiffness and strength in the aged composites......Page 317
10.3.4 Relationship between natural and accelerated ageing time......Page 318
10.3.5 Analytical model for prediction of failure time of the aged composites......Page 319
Tasi-Wu failure criterion......Page 320
10.4 Case study: evaluation of the effect of increased composite ageing on the structural integrity of the bodyshell of the Korean tilting train......Page 321
10.4.1 Structural performance before exposure to environmental factors......Page 323
10.4.2 Structural performances after exposure to environmental factors......Page 325
10.5 Conclusions......Page 327
10.6 References......Page 328
11.1 Introduction to composite structures applied in the rotorcraft industry using the example of PZL......Page 330
11.2 Potential damage that can occur in a composite main rotor blade......Page 332
11.3 Low-energy impact damage and durability in a W-3 main rotor blade......Page 336
11.3.2 Test results......Page 338
11.4 Influence of moisture and temperature......Page 340
11.5 New techniques for testing composite structures......Page 342
11.6 References......Page 343
12.1.1 Leisure craft......Page 345
12.1.3 Racing vessels......Page 346
12.2.1 Laminates......Page 347
12.2.2 Sandwich materials......Page 348
12.3 The marine environment......Page 349
12.4.1 Ageing of marine laminates......Page 350
12.4.2 Ageing under load......Page 351
12.4.3 Ageing of marine sandwich materials......Page 353
12.4.4 In-service experience......Page 354
12.5.2 Property changes......Page 356
12.6.1 Materials and ageing conditions......Page 358
12.6.2 Results and correlation with laboratory ageing......Page 359
12.7 Example 3: osmosis and blistering......Page 361
12.8.2 Water composition......Page 363
12.8.3 Influence of temperature......Page 364
12.8.5 Biological factors......Page 366
12.10 References......Page 368
Part III: Ageing of composites in non-transport applications......Page 373
13.1 Definition of medical devices......Page 374
13.2 Brief history of polyethylene used in medical devices......Page 377
13.3.1 Cross-linked polyethylene......Page 381
13.4 Ageing of polyethylene......Page 384
13.5 Future trends......Page 386
13.7 References......Page 387
14.1 Introduction......Page 392
14.2 Modelling of damage......Page 394
14.3 Ageing due to temperature......Page 401
14.4 Ageing due to chemical species......Page 403
14.5 Ageing due to applied load......Page 406
14.6 Design against ageing......Page 410
14.7 Assessment of ageing......Page 411
14.8 Examples of ageing......Page 414
14.9 Conclusions......Page 415
14.10 References......Page 416
15.1 Introduction......Page 418
15.2 Use of fibre-reinforced polymers in construction......Page 419
15.2.1 Materials used......Page 420
15.2.2 Fabrication......Page 421
15.3 Benefits of fibre-reinforced polymers for construction......Page 422
15.4.1 Service life......Page 423
15.5.1 Causes of deterioration......Page 424
15.5.5 Changes caused by weathering......Page 425
15.5.7 Prediction of durability......Page 427
Fluorescent lamps......Page 429
15.5.9 Durability in liquid environments......Page 430
15.5.10 Chemicals......Page 431
15.5.11 Effect of temperature on performance......Page 432
Fatigue......Page 433
15.6.1 Adhesively bonded joints......Page 434
15.8 Summary......Page 435
15.10 References......Page 436
16.1 High-voltage insulators......Page 438
16.2 Materials and manufacturing techniques......Page 440
16.3 Practical experiences with composite insulators......Page 441
16.4 Ageing of insulator housing......Page 445
16.4.1 Exposure to corona discharges......Page 446
16.4.2 Exposure to dry-band discharges......Page 450
16.4.3 Biological growth......Page 454
16.5 Ageing of insulator cores......Page 456
16.6 Ageing at insulator interfaces......Page 457
16.7 Future trends......Page 459
16.9 References......Page 460
17.1 Introduction......Page 465
17.2 Examples of use of fibre reinforced plastics in the chemical processing industry......Page 468
17.4 Types of degradation in fibre reinforced plastic......Page 469
17.5 Current methods for assessing long-term ageing of fibre reinforced plastics......Page 471
17.5.2 The Arrhenius relationship......Page 472
17.5.3 Using a semi-empirical corrosion approach......Page 473
17.6.1 ASTM C581......Page 474
17.6.2 Arrhenius relationship......Page 476
17.7 Concluding remarks......Page 481
17.8 References......Page 482
18.1 Introduction......Page 484
18.2.1 Chemical composition and properties of sea water......Page 485
18.2.2 Pressure and depth effects......Page 486
pH......Page 487
Other parameters......Page 488
18.3.1 Hydrothermal ageing mechanisms of polymers......Page 489
Chemical ageing......Page 491
Solubility parameters......Page 492
18.3.2 Ageing of glass in contact with water......Page 493
18.3.3 Ageing of composite material in deep sea......Page 494
18.4 Case study 1: composite tubes......Page 495
18.5 Case study 2: composite material for deep sea applications......Page 500
18.6 Case study 3: syntactic foam for deep sea and offshore applications......Page 506
18.8 References......Page 513