Designing with Plastics

Front Matter......Page 1
Table of Contents......Page 3
1. Market Overview......Page 11
1.1.1 Aerospace......Page 14
1.1.2 Precision Engineering......Page 17
1.1.3 Automotive Engineering......Page 19
1.1.4 General Mechanical Engineering......Page 24
1.1.5 Design of Technical Equipment......Page 25
1.1.6 Construction Industry......Page 28
1.2 Forecast......Page 32
References......Page 38
2.1 Chemical Structure Constitution......Page 41
2.1.1 Degree of Polymerization - Relative Molecular Weight......Page 44
2.1.2 Homopolymerization and Copolymerization......Page 48
2.2 Intermolecular Binding Energies Secondary Valence Bonds......Page 50
2.2.1 Absorption of Water by Polyamides......Page 51
2.3 Spatial Arrangement of Atoms and Groups of Atoms in Molecules Configuration......Page 57
2.3.2 Branching......Page 58
2.3.3 Cross-Linking......Page 59
2.4.1 Homogeneous and Heterogeneous Polymer Mixtures......Page 60
2.4.3 Fillers and Reinforcement......Page 61
2.5.1 Amorphous Microstructure......Page 64
2.5.2 Crystalline Microstructure......Page 65
2.5.3.1 Molecular Alignments......Page 70
2.5.3.2 Filler or Fiber Alignment......Page 72
2.6.1 Thermoplastics with Amorphous Structure......Page 74
2.6.2 Thermoplastics with Semicrystalline Structure......Page 76
2.6.4 Thermosets......Page 77
References......Page 78
3.1 Thermoplastics......Page 80
3.1.1 Polymer Blends......Page 89
3.1.2 Functional Polymers......Page 92
3.2 Elastomers......Page 97
3.3 Thermosets......Page 99
3.4 Fibrous Reinforcements......Page 103
3.4.1.1 Production and Reinforcing Forms of Glass Fiber Material......Page 104
3.4.1.2 Types of Glass and Fiber Properties......Page 105
3.4.4 Metal Fibers, Whiskers, and Ceramic Fibers......Page 106
References......Page 107
4.1.1 Molecular Deformation and Fracture Mechanisms......Page 109
4.1.2 Characteristic Stress-Strain Curves......Page 111
4.1.3 Determination of Stress-Strain Diagrams and Characteristic Properties of Materials......Page 112
4.1.4 Effects of Temperature, Time, and Humidity on Stress-Strain Curves......Page 115
4.1.5 Mathematical Description of Stress-Strain Curves......Page 117
4.2 Deformation Behavior under Uniaxial, Long-Term, Static Tensile Loads Tensile Creep Testing......Page 119
4.2.1 Mathematical Description of Creep Curves......Page 121
4.3 Toughness and Impact Resistance......Page 123
4.3.2 Determination of Toughness by Flexural Impact Test......Page 124
4.3.3 Penetration or Dart Drop Impact Test......Page 127
4.4 Behavior under Cyclic Loads......Page 128
4.4.1 Determination of Characteristic Features of Fatigue......Page 130
4.5 Poisson's Ratio......Page 133
4.6.1 Thermal Expansion......Page 135
4.6.2.1 Modulus of Elasticity and Modulus of Rigidity as a Function of Temperature......Page 137
4.6.2.2 Deflection Temperature......Page 138
4.6.2.3 Softening Point......Page 139
4.6.3 Heat Aging......Page 140
4.6.3.1 Safety Considerations and Standards......Page 143
4.7 Tribological Properties......Page 144
4.7.1 Fundamentals......Page 146
4.7.1.1 Adhesion and Surface Energy of Solids......Page 147
4.7.1.2 Deformation and Hysteresis Loss......Page 152
4.7.2 Friction and Wear in Mated Polymer and Steel Surfaces......Page 153
4.7.2.1 Effect of Steel Surface Roughness on Steel/Polymer Combinations......Page 155
4.7.2.2 Effect of Relative Molecular Weight on Friction and Wear......Page 158
4.7.2.3 Effect of the Moisture Content of Polyamides on Friction and Wear......Page 159
4.7.2.4 Effect of High-Energy Radiation......Page 161
4.7.2.5 Effect of Form and Sequence of Motion on Friction and Wear......Page 163
4.7.3.1 Sliding Friction......Page 164
4.7.3.2 Wear Due to Sliding Friction for Mated Polymeric Material Pairs......Page 165
4.7.5 Effect of Additives on Friction and Wear Properties......Page 166
4.7.5.1 Effect of Fibers on Wear......Page 167
4.7.5.3 Effect of Polymeric Additives......Page 171
4.7.6 Stick-Slip......Page 173
4.7.6.1 Changing Stick-Slip Behavior by Modifying the Parameters of the Sliding System......Page 174
4.7.7 Jet Erosion......Page 176
References......Page 179
5.1.1 Deformation Behavior under Uniaxial Dynamic Tensile Stress......Page 182
5.2.1 Basic Procedure for Structural Part Design......Page 184
5.2.1.1 Characteristic Strength......Page 185
5.2.1.2 Safety Factors......Page 187
5.2.1.3 Reducing Factors......Page 188
5.2.2 Uniaxial State of Stress......Page 189
5.2.2.1 Example of a Thin-Walled Pipe under Internal Pressure......Page 190
5.2.3.1 Failure Criteria......Page 191
5.2.3.2 Examples of Shear Loads......Page 194
5.3.1 Linear Elastic Behavior......Page 197
5.3.2 Nonlinear Elastic Behavior......Page 198
5.4 Analysis of Stress and Deformation in Structures under Flexural Loads with the Aid of a Simple FE Approach......Page 203
5.5 Calculation of Structural Parts Subjected to Impact Loads......Page 205
5.6 Structural Design of Fiber-Composite Structures......Page 206
5.6.1.2 Fundamental Elasticity Variables in a UD Layer......Page 207
5.6.1.3 Averaged Characteristic Values for Mat Laminates......Page 209
5.6.2.3 Network Theory......Page 212
5.7.1 Computer-Aided Design CAD......Page 214
5.7.2 Rapid Prototyping......Page 215
5.7.3 Rapid Tooling......Page 217
References......Page 218
6.1.1 Modulus of Elasticity......Page 220
6.1.2 Design Geometry - Moment of Inertia......Page 221
6.1.3 Load-Geometry Interactions......Page 222
6.2 Flexurally Rigid Structures......Page 225
6.3 Flexurally Flexible, Torsionally Rigid Structures......Page 227
6.5 Torsion-Resistant, Torsionally Rigid Structures......Page 228
6.6 Flexurally and Torsionally Rigid Structures......Page 231
6.8 Tension-Proof, Tensionally Rigid and Torsionally Flexible Structures......Page 232
6.9 High Shear-Strength, Shear-Resistant Structures......Page 233
6.10 Pressure-Yielding and Compression-Resistant Structures......Page 234
6.11 Multifunctional Structures......Page 236
6.12 Thermal Expansion and Thermal Stress......Page 237
6.13 Universal Joints......Page 242
References......Page 244
7.1 Mold Filling......Page 246
7.1.1 Simulation of the Filling Operation......Page 248
7.1.2 Causes of Orientation in Moldings......Page 250
7.1.2.1 Effects of Orientation......Page 253
7.1.2.2 Controlling Orientation......Page 255
7.1.3 Causes for Formation of Weld Lines and Air Pockets......Page 259
7.1.3.1 Effects of Weld Lines and Air Pockets......Page 261
7.1.3.2 Controlling Weld Lines and Air Pockets......Page 262
7.2.1.2 Controlling the Cooling Rate......Page 268
7.2.2.1 Shrinkage......Page 271
7.2.2.3 Tolerances......Page 274
7.2.3.1 Causes of Warpage......Page 278
7.2.3.2 Controlling Warpage......Page 281
7.3 Demolding......Page 284
7.3.2 Demolding of Undercuts......Page 287
7.3.2.2 Mold-Making Measures......Page 288
7.3.2.3 Fusible Cores......Page 290
7.3.3.2 Piercing Cores Blocking or Shutoffs......Page 292
7.3.3.3 Multipart Designs......Page 294
7.4.1 Two-Color Injection Molding......Page 296
7.4.2 Rigid-Flexible Combinations......Page 300
7.4.3 Gas Injection Technology GIT......Page 306
7.4.5 External Gas Pressure Technology......Page 310
References......Page 313
8.1 Snap-Fit Joints......Page 317
8.1.1.1 Types of Snap-Fit Beams......Page 323
8.1.1.2 Snap-Fit Beam Calculations......Page 327
8.1.1.3 Additional Functions......Page 328
8.1.2.1 Types of Torsional Snap-Fit Joints......Page 331
8.1.2.2 Torsion Snap-Fit Joint Calculations......Page 332
8.1.3.1 Types of Annular Snap-Fit Joints......Page 333
8.1.3.2 Annular Snap-Fit Joint Calculations......Page 334
8.1.3.3 Additional Functions......Page 336
8.1.4 Segmented Annular Snap-Fit Joints......Page 337
8.1.4.2 Slotted Annular Snap-Fit Joint Calculations......Page 338
8.1.4.3 Additional Functions......Page 340
8.2.1.1 Flexing Springs......Page 341
8.2.1.3 Compression Springs......Page 343
8.2.1.4 Torsion Springs......Page 347
8.2.2.1 Leaf Springs......Page 348
8.3 Integral Hinges and Integral Joints......Page 351
8.3.1.1 Injection Molding......Page 352
8.3.1.2 Blow Molding......Page 353
8.3.2 Design......Page 355
8.3.4 Integral Hinge Design Calculations......Page 356
8.3.4.1 Calculation of the Length and Thickness of an Integral Hinge......Page 358
8.3.5.2 Bi-Stable Hinge Joints......Page 361
8.3.5.3 Simplified Production......Page 363
8.3.5.5 Assembly Aid and Captive Binding Using Integral Hinges......Page 367
References......Page 368
9. Mechanical Fasteners......Page 371
9.1.1 Screws and Bolts Made of Polymeric Material......Page 372
9.2.2 Threaded Inserts Embedded by Ultrasound......Page 374
9.2.3 Press-In Threaded Inserts......Page 375
9.2.5 Screw-In Inserts......Page 376
9.2.7 Comparative Evaluation of the Various Inserts......Page 377
9.3 Self-Threading Screws......Page 380
9.3.1 Screw Shapes and Geometries......Page 381
9.3.2 Design of the Screw Boss......Page 383
9.3.3.2 Boss Pilot Hole Diameter......Page 384
9.3.2.4 Boss Outer Diameter......Page 385
9.3.3.1 Screw Drive Torque......Page 387
9.3.3.3 Screw Extraction Pull-Out Force......Page 389
9.3.3.4 Tightening Moment and Tensioning Force......Page 390
9.3.3.5 Assembly Conditions......Page 391
References......Page 392
10.1.1 Increasing the Modulus of Elasticity......Page 393
10.1.2 Increasing Wall Thickness......Page 394
10.1.3 Crimps and Corrugations......Page 395
10.2.1 Rib Height......Page 396
10.2.2 Rib Position......Page 397
10.2.3 Number of Ribs Consumption of Material......Page 399
10.2.4 Support......Page 401
10.3.1 Rib Thickness......Page 402
10.3.2 Cooling Time......Page 403
10.3.3 Injection Direction......Page 404
10.3.4 Rib Intersection Points Nodes......Page 406
10.4 Design Rules for Ribs Produced by Gas-Assist Molding Methods......Page 407
10.5.1 Blow-Molded Corrugations......Page 409
10.5.2 Blow-Molded Ribs......Page 411
10.6.1 Manual Processing Hand Lay-up Process......Page 412
10.6.2 Compression Molding......Page 413
References......Page 414
11. Gear Wheels......Page 416
11.1 Calculation of the Tooth and Tooth Face Temperatures in Spur Gears......Page 418
11.1.2 Takanashi Method for Calculating Temperature......Page 419
11.1.3 Hachmann and Strickle Method for Calculating Temperature......Page 421
11.1.4 Comparison of Methods of Calculating Temperature......Page 423
11.1.5 Optimized Temperature Calculation......Page 424
11.1.5.2 Flank Temperature......Page 425
11.1.5.3 Relative Contact Time......Page 427
11.1.5.4 Optimized Numerical Value Equation......Page 428
11.2 Calculation of Load-Bearing Capacity......Page 429
11.2.1 Tooth Damage......Page 430
11.2.2 General Parameters......Page 431
11.2.3 Calculation of the Load-Bearing Capacity of the Tooth Base......Page 432
11.2.4 Calculation of the Load-Bearing Capacity of the Tooth Flank......Page 439
11.2.5 Calculation of Tooth Deformation......Page 445
11.3.1 Injection Molding......Page 447
11.3.2 Production of Gears by Machining......Page 451
11.3.3.1 Press-Fit Joints......Page 452
11.3.3.2 Form-Grip Joints......Page 455
11.3.3.3 Pretensioned Form-Grip Joints......Page 457
References......Page 460
12. Friction Bearings......Page 463
12.1 Friction Bearing Damage......Page 465
12.2.1 Calculation of Mean Bearing Temperature......Page 467
12.2.3 Static Load-Bearing Capacity......Page 470
12.2.3.1 Load on the Bearing Material......Page 471
12.2.3.2 Deformation of the Bearing Bushing......Page 475
12.2.4.1 Continuous Operation......Page 479
12.2.4.2 Intermittent Operation......Page 480
12.2.4.3 Wear......Page 481
12.3.1 Bearing Clearance......Page 482
12.3.2 Bearing Wall Thickness......Page 484
12.3.4 Design Examples of Bearings......Page 485
References......Page 487
13. Wheels and Rollers......Page 488
13.1 Roller Damage......Page 489
13.2.1 Pressure Parameter as an Approximate Design Limit......Page 491
13.2.2 Deformation of Rollers under Static Load......Page 495
13.2.3.1 Free-Wheeling Rollers without Drive......Page 501
13.2.3.2 Driven Rollers......Page 507
References......Page 510
A......Page 512
B......Page 513
C......Page 515
D......Page 517
E......Page 518
F......Page 519
G......Page 521
I......Page 522
L......Page 524
M......Page 525
O......Page 526
P......Page 527
R......Page 529
S......Page 531
T......Page 534
V......Page 536
Y......Page 537