Enhanced descriptions from Syndetics:

A reference on making cost effective design decisions and ensuring that parts and products designed stand up under use. A detailed yet simplified discussion of material selection, manufacturing techniques, and assembly procedures enables readers to evaluate plastic materials and to adequately design plastic parts for assembly. Descriptions of good joint design, the geometry of component parts, and types of load involved focus on everyday problems and solutions. The author is a consultant serving the plastics and automotive industries, and a Fellow of the International Society of Plastics Engineers. Annotation copyrighted by Book News, Inc., Portland, OR

Table of contents provided by Syndetics

• Introduction (p. xvii)
• 1 Understanding Plastic Materials (p. 1)
• 1.1 Basic Resins (p. 1)
• 1.1.1 Thermoplastics (p. 1)
• 1.1.2 Thermosets (p. 2)
• 1.2 Basic Structures (p. 2)
• 1.2.1 Crystalline (p. 2)
• 1.2.2 Amorphous (p. 3)
• 1.2.3 Liquid Crystal Polymer (p. 3)
• 1.2.4 New Polymer Technologies (p. 4)
• 1.2.4.1 Inherently Conductive Polymers (ICP) (p. 4)
• 1.2.4.2 Electro-Optic Polymers (EOP) (p. 5)
• 1.2.4.3 Biopolymers (p. 6)
• 1.3 Homopolymer vs. Copolymer (p. 6)
• 1.4 Reinforcements (p. 7)
• 1.5 Fillers (p. 7)
• 1.5.1 Glass Sphere (p. 8)
• 1.5.1.1 Microphere Properties (p. 8)
• 1.5.1.2 Compounding (p. 9)
• 1.5.1.3 Injection Molding (p. 10)
• 1.5.1.4 Mechanical Properties in Injection Molded Thermoplastic Applications (p. 10)
• 1.6 Additives (p. 11)
• 1.7 Physical Properties (p. 12)
• 1.7.1 Density and Specific Gravity (p. 12)
• 1.7.2 Elasticity (p. 13)
• 1.7.3 Plasticity (p. 14)
• 1.7.4 Ductility (p. 14)
• 1.7.5 Toughness (p. 14)
• 1.7.6 Brittleness (p. 15)
• 1.7.7 Notch Sensitivity (p. 15)
• 1.7.8 Isotropy (p. 20)
• 1.7.9 Anisotropy (p. 20)
• 1.7.10 Water Absorption (p. 20)
• 1.7.11 Mold Shrinkage (p. 21)
• 1.8 Mechanical Properties (p. 23)
• 1.8.1 Normal Stress (p. 23)
• 1.8.2 Normal Strain (p. 23)
• 1.8.3 Stress-Strain Curve (p. 24)
• 1.9 Creep (p. 26)
• 1.9.1 Introduction (p. 26)
• 1.9.2 Creep Experiments (p. 26)
• 1.9.3 Creep Curves (p. 27)
• 1.9.4 Stress-Relaxation (p. 29)
• 1.10 Impact Properties (p. 29)
• 1.11 Thermal Properties (p. 31)
• 1.11.1 Melting Point (p. 31)
• 1.11.2 Glass Transition Temperature (p. 31)
• 1.11.3 Heat Deflection Temperature (p. 31)
• 1.11.4 Coefficient of Thermal Expansion (p. 31)
• 1.11.5 Thermal Conductivity (p. 33)
• 1.11.6 Thermal Influence on Mechanical Properties (p. 33)
• 1.11.7 Case History: Planetary Gear Life Durability (p. 34)
• 2 Understanding Safety Factors (p. 40)
• 2.1 What Is a Safety Factor (p. 40)
• 2.2 Using the Safety Factors (p. 40)
• 2.2.1 Design Safety Factors (p. 40)
• 2.2.1.1 Design Static Safety Factor (p. 41)
• 2.2.1.2 Design Dynamic Safety Factor (p. 41)
• 2.2.1.3 Design Time-related Safety Factor (p. 41)
• 2.2.2 Material Properties Safety Factor (p. 42)
• 2.2.3 Processing Safety Factors (p. 43)
• 2.2.4 Operating Condition Safety Factor (p. 43)
• 3 Strength of Material for Plastics (p. 44)
• 3.1 Tensile Strength (p. 44)
• 3.1.1 Proportional Limit (p. 45)
• 3.1.2 Elastic Stress Limit (p. 45)
• 3.1.3 Yield Stress (p. 45)
• 3.1.4 Ultimate Stress (p. 46)
• 3.2 Compressive Stress (p. 46)
• 3.3 Shear Stress (p. 47)
• 3.4 Torsion Stress (p. 48)
• 3.5 Elongations (p. 49)
• 3.5.1 Tensile Strain (p. 49)
• 3.5.2 Compressive Strain (p. 51)
• 3.5.3 Shear Strain (p. 51)
• 3.6 True Stress and Strain vs. Engineering Stress and Strain (p. 51)
• 3.7 Poisson's Ratio (p. 52)
• 3.8 Modulus of Elasticity (p. 54)
• 3.8.1 Young's Modulus (p. 54)
• 3.8.2 Tangent Modulus (p. 55)
• 3.8.3 Secant Modulus (p. 56)
• 3.8.4 Creep (Apparent) Modulus (p. 56)
• 3.8.5 Shear Modulus (p. 57)
• 3.8.6 Flexural Modulus (p. 57)
• 3.8.7 The Use of Various Moduli (p. 58)
• 3.9 Stress Relations (p. 58)
• 3.9.1 Introduction (p. 58)
• 3.9.2 Experiment (p. 59)
• 3.9.3 Equivalent Stress (p. 59)
• 3.9.4 Maximum Normal Stress (p. 59)
• 3.9.5 Maximum Normal Strain (p. 60)
• 3.9.6 Maximum Shear Stress (p. 60)
• 3.9.7 Maximum Deformation Energy (p. 61)
• 3.10 Conclusions (p. 62)
• 4 Nonlinear Considerations (p. 63)
• 4.1 Material Considerations (p. 63)
• 4.1.1 Linear Material (p. 63)
• 4.1.2 Nonlinear Material (p. 63)
• 4.2 Geometry (p. 64)
• 4.2.1 Linear Geometry (p. 64)
• 4.2.2 Nonlinear Geometry (p. 64)
• 4.3 Finite Element Analysis (FEA) (p. 65)
• 4.3.1 FEA Method Application (p. 65)
• 4.3.2 Using FEA Method (p. 65)
• 4.3.3 Most Common FEA Codes (p. 66)
• 4.4 Conclusions (p. 66)
• 5 Assembly Techniques for Plastics (p. 67)
• 5.1 Ultrasonic Welding (p. 67)
• 5.1.1 Ultrasonic Equipment (p. 67)
• 5.1.2 Horn Design (p. 70)
• 5.1.3 Ultrasonic Welding Techniques (p. 72)
• 5.1.4 Control Methods (p. 75)
• 5.1.5 Common Issues with Welding (p. 78)
• 5.1.6 Joint Design (p. 81)
• 5.1.6.1 Butt Joint Design (p. 82)
• 5.1.6.2 Shear Joint Design (p. 83)
• 5.2 Ultrasonic (Heat) Staking (p. 86)
• 5.2.1 Standard Stake Design (p. 86)
• 5.2.2 Flush Stake Design (p. 87)
• 5.2.3 Spherical Stake Design (p. 88)
• 5.2.4 Hollow (Boss) Stake Design (p. 89)
• 5.2.5 Knurled Stake Design (p. 90)
• 5.3 Ultrasonic Spot Welding (p. 91)
• 5.4 Ultrasonic Swaging (p. 92)
• 5.5 Ultrasonic Stud Welding (p. 92)
• 5.6 Spin Welding (p. 93)
• 5.6.1 Process (p. 93)
• 5.6.2 Equipment (p. 96)
• 5.6.3 Welding Parameters (p. 96)
• 5.6.4 Joint Design (p. 97)
• 5.7 Hot Plate Welding (p. 100)
• 5.7.1 Process (p. 103)
• 5.7.2 Joint Design (p. 104)
• 5.8 Vibration Welding (p. 106)
• 5.8.1 Process (p. 108)
• 5.8.2 Equipment (p. 110)
• 5.8.3 Joint Design (p. 111)
• 5.8.4 Common Issues with Vibration Welding (p. 113)
• 5.9 Electromagnetic Welding (p. 114)
• 5.9.1 Equipment (p. 115)
• 5.9.2 Process (p. 115)
• 5.9.3 Joint Design (p. 116)
• 5.10 Solvent and Adhesive Bonding (p. 118)
• 5.10.1 Types of Adhesives (p. 119)
• 5.10.2 Advantages and Limitations of Adhesives (p. 120)
• 5.10.3 Stress Cracking in Bonded Joints (p. 120)
• 5.10.4 Joint Design (p. 121)
• 5.11 Radio Frequency (RF) Welding (p. 123)
• 5.11.1 Equipment (p. 123)
• 5.11.2 Process (p. 124)
• 5.12 Laser Welding (p. 125)
• 5.12.1 Equipment (p. 125)
• 5.12.2 Process (p. 127)
• 5.12.2.1 Surface Heating (p. 128)
• 5.12.2.2 Through Transmission (p. 128)
• 5.12.2.3 Staking (p. 129)
• 5.12.3 Techniques for Laser Welding (p. 130)
• 5.12.4 Polymers (p. 132)
• 5.12.5 Applications (p. 134)
• 5.13 Conclusion (p. 137)
• 6 Press Fitting (p. 138)
• 6.1 Introduction (p. 138)
• 6.2 Definitions and Notations (p. 138)
• 6.3 Geometric Definitions (p. 139)
• 6.4 Safety Factors (p. 139)
• 6.5 Creep (p. 140)
• 6.6 Loads (p. 140)
• 6.7 Press Fit Theory (p. 141)
• 6.8 Design Algorithm (p. 143)
• 6.9 Case History: Plastic Shaft - Plastic Hub (p. 144)
• 6.9.1 Shaft and Hub Made of Different Polymers (p. 144)
• 6.9.2 Safety Factor Selection (p. 144)
• 6.9.3 Material Properties (p. 145)
• 6.9.3.1 Shaft - Material Properties at 23 ° [Page No. xiv]C (p. 145)
• 6.9.3.2 Shaft - Material Properties at 93 °C (p. 149)
• 6.9.3.3 Creep Curves at 23 °C (p. 150)
• 6.9.3.4 Creep at 93 °C (p. 151)
• 6.9.3.5 Pulley at 23 °C (p. 152)
• 6.9.3.6 Pulley at 93 °C (p. 155)
• 6.9.3.7 Creep, Pulley at 23 °C (p. 156)
• 6.9.3.8 Creep, Pulley at 93 °C (p. 157)
• 6.10 Solutions: Plastic Shaft - Plastic Hub (p. 158)
• 6.10.1 Case A (p. 158)
• 6.10.2 Case B (p. 159)
• 6.10.3 Case C (p. 160)
• 6.10.4 Case D (p. 161)
• 6.11 Case History: Metal Ball Bearing - Plastic Hub (p. 163)
• 6.11.1 Fusible Core Injection Molding (p. 163)
• 6.11.2 Upper Intake Manifold Background (p. 164)
• 6.11.3 Design Algorithm (p. 167)
• 6.11.4 Material Properties (p. 168)
• 6.11.4.1 CAMPUS (p. 169)
• 6.11.5 Solution (p. 170)
• 6.11.5.1 Necessary IF at Ambient (p. 174)
• 6.11.5.2 IF Available at 118 °C (p. 175)
• 6.11.5.3 IF Verification at -40 °C (p. 175)
• 6.11.5.4 Stress Check at -40 °C, Time = 0 (p. 176)
• 6.11.5.5 Stress Level at -40 °C, Time = 5,000 h (p. 176)
• 6.11.5.6 Stress Level at 23 °C, Time = 5,000 h (p. 176)
• 6.11.5.7 Stress Level at 118 °C, Time = 5,000 h (p. 177)
• 6.11.6 Conclusion (p. 177)
• 7 Living Hinges (p. 178)
• 7.1 Introduction (p. 178)
• 7.2 Basic Design for PP, PE (p. 178)
• 7.3 Common Living Hinge Design (p. 180)
• 7.4 Basic Design for Engineering Plastics (p. 180)
• 7.5 Living Hinge Design Analysis (p. 181)
• 7.5.1 Elastic Strain Due to Bending (p. 181)
• 7.5.1.1 Assumptions (p. 181)
• 7.5.1.2 Geometric Conditions (p. 182)
• 7.5.1.3 Strain Due to Bending (p. 182)
• 7.5.1.4 Stress Due to Bending (p. 183)
• 7.5.1.5 Closing Angle of the Hinge (p. 184)
• 7.5.1.6 Bending Radius of the Hinge (p. 184)
• 7.5.2 Plastic Strain Due to Pure Bending (p. 184)
• 7.5.2.1 Assumptions (p. 184)
• 7.5.2.2 Strain Due to Bending (p. 184)
• 7.5.3 Plastic Strain Due to a Mixture of Bending and Tension (p. 186)
• 7.5.3.1 Tension Strain (p. 186)
• 7.5.3.2 Bending Strain (p. 189)
• 7.5.3.3 Neutral Axis Position (p. 190)
• 7.5.3.4 Hinge Length (p. 190)
• 7.5.3.5 Elastic Portion of the Hinge Thickness (p. 193)
• 7.6 Computer Flow Chart (p. 194)
• 7.6.1 Computer Notations (p. 194)
• 7.7 Computer Flow Chart Equations (p. 196)
• 7.8 Example: Case History (p. 198)
• 7.8.1 World Class Connector (p. 198)
• 7.8.1.1 Calculations for the 'Right Way' Assembly (p. 199)
• 7.8.1.2 Calculations for the 'Wrong Way' Assembly (p. 201)
• 7.8.2 Comparison Material (p. 203)
• 7.8.2.1 'Right Way' Assembly (p. 203)
• 7.8.2.2 'Wrong Way' Assembly (p. 204)
• 7.8.3 Ignition Cable Bracket (p. 205)
• 7.8.3.1 Initial Design (p. 206)
• 7.8.3.2 Improved Design (p. 206)
• 7.9 Processing Errors for Living Hinges (p. 208)
• 7.10 Coined Hinges (p. 209)
• 7.11 Conclusion (p. 212)
• 7.12 Exercise (p. 212)
• 8 Snap Fitting (p. 218)
• 8.1 Introduction (p. 218)
• 8.2 Material Considerations (p. 219)
• 8.3 Design Considerations (p. 221)
• 8.3.1 Safety Factors (p. 223)
• 8.4 Snap Fit Theory (p. 224)
• 8.4.1 Notations (p. 224)
• 8.4.2 Geometric Conditions (p. 225)
• 8.4.3 Stress Strain Curve and Formulae (p. 226)
• 8.4.4 Instantaneous Moment of Inertia (p. 229)
• 8.4.5 Angle of Deflection (p. 229)
• 8.4.6 Integral Solution (p. 229)
• 8.4.7 Equation of Deflection (p. 231)
• 8.4.8 Integral Solution (p. 232)
• 8.4.9 Maximum Deflection (p. 232)
• 8.4.10 Self-locking Angle (p. 235)
• 8.5 Case History: One-way Continuous Beam with Rectangular Cross Section (p. 235)
• 8.5.1 Geometrical Model (p. 237)
• 8.6 Annular Snap Fits (p. 240)
• 8.6.1 Case History: Annular Snap Fit - Rigid Beam with Soft Mating Part (p. 241)
• 8.6.2 Notations (p. 241)
• 8.6.3 Geometric Definitions (p. 242)
• 8.6.4 Material Selections and Properties (p. 242)
• 8.6.5 Basic Formulas (p. 243)
• 8.6.6 Angle of Assembly (p. 244)
• 8.7 Torsional Snap Fits (p. 245)
• 8.7.1 Notations (p. 245)
• 8.7.2 Basic Formulae (p. 247)
• 8.7.3 Material Properties (p. 248)
• 8.7.4 Solution (p. 248)
• 8.8 Case History: Injection Blow Molded Bottle Assembly (p. 250)
• 8.9 Tooling (p. 251)
• 8.10 Assembly Procedures (p. 252)
• 8.11 Issues with Snap Fitting (p. 254)
• 8.12 Serviceability (p. 255)
• 8.13 Conclusions (p. 255)
• Appendix A Enforced Displacement (p. 257)
• Appendix B Point Force (p. 266)
• References (p. 276)
• World Wide Web References Related to Plastic Part Design (p. 283)
• Index (p. 287)

Author notes provided by Syndetics