Introduction to aerospace materials

636 Pages·2012·20.86 MB·English

by  Adrian P. Mouritz

Introduction to aerospace materials
© Woodhead Publishing Limited, 2012
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© Woodhead Publishing Limited, 2012
Introduction
to aerospace
materials
Adrian P. Mouritz
Oxford Cambridge Philadelphia New Delhi
© Woodhead Publishing Limited, 2012
Published by Woodhead Publishing Limited,
80 High Street, Sawston, Cambridge CB22 3HJ, UK
www.woodheadpublishing.com
Woodhead Publishing, 1518 Walnut Street, Suite 1100, Philadelphia, PA 19102-3406, USA
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First published 2012, Woodhead Publishing Limited
© Woodhead Publishing Limited, 2012
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ISBN 978-0-85709-515-2 (online)
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© Woodhead Publishing Limited, 2012
Contents
Preface xiii
1 Introduction to aerospace materials 1
1.1 The importance of aerospace materials 1
1.2 Understanding aerospace materials 2
1.3 Introducing the main types of aerospace materials 4
1.4 What makes for a good aerospace material? 11
1.5 Summary 13
1.6 Further reading and research 14
2 Aerospace materials: past, present and future 15
2.1 Introduction 15
2.2 Brief history of aerospace materials 19
2.3 Materials for the global aerospace industry 32
2.4 Future advances in aerospace materials 35
2.5 Summary 37
2.6 Further reading and research 38
3 Materials and material requirements for aerospace
structures and engines 39
3.1 Introduction 39
3.2 Fixed-wing aircraft structures 40
3.3 Helicopter structures 51
3.4 Space shuttle structures 54
3.5 Summary 55
3.6 Further reading and research 56
4 Strengthening of metal alloys 57
4.1 Introduction 57
4.2 Crystal structure of metals 58
4.3 Defects in crystal structures 60
© Woodhead Publishing Limited, 2012
vi Contents
4.4 Strengthening of metals 68
4.5 Summary 87
4.6 Terminology 88
4.7 Further reading and research 89
5 Mechanical and durability testing of aerospace
materials 91
5.1 Introduction 91
5.2 Tension test 92
5.3 Compression test 106
5.4 Flexure test 107
5.5 Hardness test 108
5.6 Fracture test 111
5.7 Drop-weight impact test 113
5.8 Fatigue test 114
5.9 Creep test 115
5.10 Environmental durability testing 116
5.11 Certification of aerospace materials 118
5.12 Summary 123
5.13 Terminology 126
5.14 Further reading and research 127
6 Production and casting of aerospace metals 128
6.1 Introduction 128
6.2 Production of metal alloys 128
6.3 Casting of metal alloys 134
6.4 Casting processes 143
6.5 Summary 149
6.6 Terminology 150
6.7 Further reading and research 151
6.8 Case study: casting defects causing engine disc failure in
United Airlines flight 232 151
7 Processing and machining of aerospace metals 154
7.1 Introduction 154
7.2 Metal-forming processes 156
7.3 Hot and cold working of metal products 161
7.4 Powder metallurgy for production of aerospace
superalloys 167
7.5 Machining of metals 168
7.6 Summary 170
7.7 Terminology 171
© Woodhead Publishing Limited, 2012
Contents vii
7.8 Further reading and research 172
8 Aluminium alloys for aircraft structures 173
8.1 Introduction 173
8.2 Aluminium alloy types 175
8.3 Non-age-hardenable aluminium alloys 179
8.4 Age-hardenable aluminium alloys 181
8.5 Speciality aluminium alloys 186
8.6 Heat treatment of age-hardenable aluminium alloys 188
8.7 High-temperature strength of aluminium 197
8.8 Summary 200
8.9 Further reading and research 201
9 Titanium alloys for aerospace structures and engines 202
9.1 Introduction 202
9.2 Titanium alloys: advantages and disadvantages for
aerospace applications 205
9.3 Types of titanium alloy 207
9.4 Titanium aluminides 216
9.5 Shape-memory titanium alloys 218
9.6 Summary 221
9.7 Terminology 222
9.8 Further reading and research 223
10 Magnesium alloys for aerospace structures 224
10.1 Introduction 224
10.2 Metallurgy of magnesium alloys 225
10.3 Summary 231
10.4 Further reading and research 231
11 Steels for aircraft structures 232
11.1 Introduction 232
11.2 Basic principles of steel metallurgy 234
11.3 Maraging steel 244
11.4 Medium-carbon low-alloy steel 246
11.5 Stainless steel 246
11.6 Summary 247
11.7 Terminology 249
11.8 Further reading and research 249
12 Superalloys for gas turbine engines 251
12.1 Introduction 251
© Woodhead Publishing Limited, 2012
viii Contents
12.2 A simple guide to jet engine technology 254
12.3 Nickel-based superalloys 256
12.4 Iron–nickel superalloys 262
12.5 Cobalt superalloys 262
12.6 Thermal barrier coatings for jet engine alloys 263
12.7 Advanced materials for jet engines 265
12.8 Summary 265
12.9 Further reading and research 266
13 Polymers for aerospace structures 268
13.1 Introduction 268
13.2 Aerospace applications of polymers 270
13.3 Advantages and disadvantages of polymers for
aerospace applications 270
13.4 Polymerisation 271
13.5 Thermosetting polymers 276
13.6 Thermoplastics 279
13.7 Elastomers 283
13.8 Structural adhesives 285
13.9 Mechanical properties of polymers 288
13.10 Polymer additives 294
13.11 Polymers for radar-absorbing materials (RAMs) 296
13.12 Summary 298
13.13 Terminology 299
13.14 Further reading and research 301
13.15 Case study: space shuttle Challenger accident 301
14 Manufacturing of fibre–polymer composite
materials 303
14.1 Introduction 303
14.2 Fibre reinforcements for composites 306
14.3 Production of prepregs and fabrics 315
14.4 Core materials for sandwich composites 319
14.5 Composites manufacturing using prepreg 321
14.6 Composites manufacturing by resin infusion 326
14.7 Machining of composites 333
14.8 Summary 334
14.9 Terminology 335
14.10 Further reading and research 336
14.11 Case study: carbon nanotubes in composites 336
© Woodhead Publishing Limited, 2012
Contents ix
15 Fibre–polymer composites for aerospace
structures and engines 338
15.1 Introduction 338
15.2 Types of composite materials 339
15.3 Aerospace applications of fibre–polymer composites 342
15.4 Advantages and disadvantages of using fibre–polymer
composites 348
15.5 Mechanics of continuous-fibre composites 354
15.6 Sandwich composites 378
15.7 Environmental durability of composites 384
15.8 Summary 390
15.9 Terminology 392
15.10 Further reading and research 393
16 Metal matrix, fibre–metal and ceramic matrix
composites for aerospace applications 394
16.1 Metal matrix composites 394
16.2 Fibre–metal laminates 400
16.3 Ceramic matrix composites 402
16.4 Summary 406
16.5 Terminology 407
16.6 Further reading and research 408
16.7 Case study: ceramic matrix composities in the space
shuttle orbiter 408
17 Wood in small aircraft construction 411
17.1 Introduction 411
17.2 Advantages and disadvantages of wood 412
17.3 Hardwoods and softwoods 412
17.4 Structure and composition of wood 414
17.5 Engineering properties of wood 418
17.6 Summary 424
17.7 Terminology 425
17.8 Further reading and research 426
17.9 Case study: Spruce Goose (Hughes H-4 Hercules) 426
18 Fracture processes of aerospace materials 428
18.1 Introduction 428
18.2 Fracture processes of aerospace materials 431
18.3 Stress concentration effects in materials 439
18.4 Fracture mechanics 444
18.5 Application of fracture mechanics to aerospace materials 448
© Woodhead Publishing Limited, 2012
x Contents
18.6 Summary 449
18.7 Terminology 450
18.8 Further reading and research 451
18.9 Case study: fracture in the space shuttle Columbia disaster 451
18.10 Case study: fracture of aircraft composite radome 452
19 Fracture toughness properties of aerospace
materials 454
19.1 Introduction 454
19.2 Fracture toughness properties 454
19.3 Ductile/brittle fracture transition for metals 463
19.4 Improving the fracture toughness of aerospace materials 465
19.5 Summary 467
19.6 Terminology 468
19.7 Further reading and research 468
20 Fatigue of aerospace materials 469
20.1 Introduction 469
20.2 Fatigue stress 470
20.3 Fatigue life (S–N) curves 475
20.4 Fatigue-crack growth curves 477
20.5 Fatigue of metals 480
20.6 Fatigue of fibre–polymer composites 487
20.7 Fretting, acoustic and thermal fatigue 492
20.8 Summary 493
20.9 Terminology 494
20.10 Further reading and research 495
20.11 Case study: aircraft fatigue in Japan Airlines flight 123 495
20.12 Case study: metal fatigue in Comet aircraft accidents 496
21 Corrosion of aerospace metals 498
21.1 Introduction 498
21.2 Corrosion process 501
21.3 Types of corrosion 504
21.4 Corrosion protection of metals 513
21.5 Summary 517
21.6 Terminology 517
21.7 Further reading and research 518
21.8 Case study: corrosion in the Aloha Airlines flight 243 519
22 Creep of aerospace materials 521
22.1 Introduction 521
© Woodhead Publishing Limited, 2012