Advanced Materials and Design for Electromagnetic Interference Shielding: Advanced Materials and Design for Electromagnetic Interference Shielding.pdf

Contents
Preface.................................................................................................................... xiii
Author......................................................................................................................xv
Chapter 1 Electromagnetic Interference Shielding Fundamentals.
and Design Guide................................................................................1
1.1 Concepts of Electromagnetic Interference and Electromagnetic
Compatibility...................................................................................................1
1.1.1 EMI Problems and Common Concerns............................................2
1.1.2 EMI Emissions and Controlling Methods........................................3
1.1.2.1 Conducted EMI Emission.................................................4
1.1.2.2 Radiated EMI Emission....................................................5
1.1.3 EMC Regulations and Testing Standards.........................................8
1.1.3.1 The International Standard...............................................9
1.1.3.2 FCC Standard...................................................................9
1.1.3.3 European Standard......................................................... 10
1.1.3.4 Military Standard........................................................... 10
1.2 EMI Shielding Principles............................................................................... 11
1.2.1 Shielding Effects in the E-Field and H-Field.................................. 11
1.2.2 Shielding Effectiveness................................................................... 13
1.2.2.1 Absorption Loss.............................................................. 14
1.2.2.2 Reflection Loss............................................................... 15
1.2.2.3 Multiple Reflection Correction Factor............................ 16
1.2.3 Shielding Modeling in Practice....................................................... 18
1.2.3.1 Metallic Enclosure.......................................................... 18
1.2.3.2 EMI Gasket..................................................................... 19
1.2.3.3 Shield with Apertures.....................................................20
1.2.3.4 Cavity Resonance............................................................23
1.3 EMC Design Guidelines and EMI Shielding Methodology..........................24
1.3.1 Design for EMC..............................................................................24
1.3.2 Shielding Methods and Materials Selection...................................27
1.3.2.1 Shielding Housing and Enclosures.................................27
1.3.2.2 Gasketing........................................................................29
1.3.2.3 Integral Assembly...........................................................30
1.3.2.4 Corrosion and Material Galvanic Compatibility............ 31
1.3.3 Environmental Compliance............................................................ 32
1.3.3.1 RoHS Directive............................................................... 33
1.3.3.2 WEEE Directive.............................................................34
References................................................................................................................. 35
Chapter 2 Characterization Methodology of EMI Shielding Materials............37
2.1 Shielding Effectiveness Measurement...........................................................37
2.1.1 Testing Methods Based on MIL-STD-285......................................38
2.1.2 Modified Radiation Method for Shielding Effectiveness
Testing Based on MIL-G-83528.....................................................39
2.1.3 Dual Mode Stirred Chamber...........................................................39
2.1.4 Transverse Electromagnetic (TEM) Cell........................................40
2.1.5 Circular Coaxial Holder.................................................................. 42
2.1.6 Dual Chamber Test Fixture Based on ASTM ES7-83.................... 42
2.1.7 Transfer Impedance Methods.......................................................... 42
2.1.7.1 Transfer Impedance of Coaxial Cables.......................... 43
2.1.7.2 Transfer Impedance Method for Shielding
Effectiveness Measurement of Conductive Gaskets....... 43
2.2 Electrical and Thermal Conductivities.......................................................... 45
2.2.1 Electrical Conductivity and Contact Resistance............................. 45
2.2.2 Thermal Conductivity.....................................................................46
2.3 Permeability and Permittivity........................................................................ 47
2.3.1 Permeability.................................................................................... 47
2.3.2 Permittivity......................................................................................48
2.3.3 Characterization of Permeability and Permittivity.........................48
2.4 Mechanical Properties...................................................................................49
2.4.1 Uniaxial Tensile Testing..................................................................49
2.4.2 Hardness..........................................................................................50
2.4.3 Poisson’s Ratio.................................................................................50
2.4.4 Stress Relaxation.............................................................................50
2.4.5 Contact Force.................................................................................. 51
2.4.6 Friction Force.................................................................................. 52
2.4.7 Permanent Set.................................................................................. 52
2.5 Surface Finish and Contact Interface Compatibility..................................... 52
2.5.1 Corrosion and Oxidation Protection............................................... 53
2.5.1.1 Noble Finish Selection.................................................... 53
2.5.1.2 Nonnoble Finishes..........................................................54
2.5.2 Solderability of Surface Finishes.................................................... 55
2.5.3 Effects of Mating Cycles and Operating Environments.
on Contact Finishes......................................................................... 57
2.5.4 Galvanic Corrosion and Contact Interface Compatibility..............58
2.6 Formability and Manufacturability................................................................58
2.6.1 Bending Formability.......................................................................59
2.6.2 Effect of Strain Hardening on Formability.....................................60
2.6.3 Anisotropy Coefficient.................................................................... 61
2.6.4 Springback during Metal Strip Forming......................................... 62
2.7 Environmental Performance Evaluation........................................................ 62
2.7.1 Thermal Cycling.............................................................................63
2.7.2 Thermal Aging................................................................................63
2.7.3 Gaseous Testing...............................................................................63
2.7.4 Pore Corrosion and Fretting Corrosion...........................................63
2.7.5 Temperature and Humidity Testing................................................64
2.7.6 Dust Sensitivity Test........................................................................64
2.7.7 Vibration and Shock Test................................................................65
References.................................................................................................................65
Chapter 3 EMI Shielding Enclosure and Access............................................... 67
3.1 Enclosure Design and Materials Selection.................................................... 67
3.2 Magnetic Field Shielding Enclosure..............................................................73
3.2.1 Basics of Magnetic Shielding..........................................................73
3.2.2 Magnetic Shielding Materials Selection......................................... 74
3.2.3 Magnetic Shielding Enclosure Design Consideration..................... 76
3.3 Shielding Enclosure Integrity........................................................................ 78
3.4 Specialized Materials Used for Shielding Enclosure.....................................82
3.4.1 EMI Gaskets....................................................................................82
3.4.1.1 Metal Strip Gaskets........................................................82
3.4.1.2 Knitted Metal Wire Gaskets...........................................83
3.4.1.3 Metal-Plated Fabric-over-Foam (FOF)...........................84
3.4.1.4 Electrically Conductive Elastomer (ECE) Gaskets........84
3.4.2 Magnetic Screening Materials........................................................84
3.4.3 Shielding Tapes...............................................................................85
3.4.4 Thermoformable Alloys..................................................................85
3.4.5 Honeycomb Materials.....................................................................85
3.4.6 Painted or Plated Plastic Enclosures...............................................86
3.4.7 Conductive Composite Shielding Materials....................................86
3.5 Summary........................................................................................................86
References.................................................................................................................87
Chapter 4 Metal-Formed EMI Gaskets and Connectors...................................89
4.1 Introduction....................................................................................................89
4.2 Metal Strip Selection and Performance Requirement...................................90
4.3 Copper Beryllium Alloys............................................................................... 91
4.3.1 Phase Constitution and Primary Processing of CuBe Strips.......... 91
4.3.2 Performance and Availability of CuBe Alloys...............................95
4.3.2.1 High-Strength Alloys......................................................95
4.3.2.2 High-Conductivity CuBe Alloys....................................97
4.3.2.3 Nickel Beryllium.............................................................97
4.4 Copper–Nickel–Tin Spinodal Alloys.............................................................97
4.4.1 Composition and Physical Properties..............................................97
4.4.2 Strip Gauges and Temper Designations..........................................99
4.4.3 Mechanical Properties and Bending Formability.........................100
4.4.4 Stress-Relaxation Resistance......................................................... 101
4.4.5 Heat Treatment and Spinodal Decomposition.............................. 101
4.4.6 Surface Cleaning, Plating, and Soldering..................................... 103
4.4.7 Elastic Performance...................................................................... 103
4.4.8 Shielding Effectiveness................................................................. 104
4.4.9 Fatigue Strength............................................................................104
4.4.10 Some Considerations to Improve Performance.
of CuNiSn Gasketing.................................................................... 105
4.5 Copper–Titanium Alloy............................................................................... 107
4.6 Stainless Steel.............................................................................................. 108
4.7 Other Materials Options.............................................................................. 110
4.7.1 Phosphor Bronze........................................................................... 110
4.7.2 Brass.............................................................................................. 111
4.7.3 Nickel Silver.................................................................................. 111
4.7.4 Other High Strength and High Conductive Copper Alloys.......... 112
4.8 Design Guideline of Metal Gaskets and Connectors................................... 113
4.8.1 Primary Approaches..................................................................... 114
4.8.2 Some Special Design Options....................................................... 115
4.8.3 Gasketing Design Guideline......................................................... 116
4.9 Fabrication Process and Types of Metal Gaskets and Connectors.............. 118
4.9.1 Progressive Die Forming............................................................... 118
4.9.2 Roll Forming................................................................................. 119
4.9.3 Multiple-Slide Stamping...............................................................120
4.9.4 Photoetching..................................................................................120
4.9.5 Typical Part Profiles......................................................................120
4.10 Mounting Methods and Surface Mating Assurance.................................... 122
4.11 Summary......................................................................................................124
References...............................................................................................................124
Chapter 5 Conductive Elastomer and Flexible Graphite Gaskets.................... 127
5.1 Introduction.................................................................................................. 127
5.2 Raw Material Selection and Conductive Elastomer Fabrication.................128
5.2.1 Base Binder Materials...................................................................128
5.2.1.1 Silicone.........................................................................128
5.2.1.2 Fluorosilicone............................................................... 129
5.2.1.3 Ethylene Propylene Diene Monomer (EPDM)............. 129
5.2.1.4 Fluorocarbon................................................................. 129
5.2.1.5 Natural Rubber and Butadiene-Acrylonitrile............... 129
5.2.2 Conductive Fillers......................................................................... 129
5.2.3 Fabrication of Conductive Elastomer Materials............................ 130
5.3 Conduction Mechanism and Processing Optimization of Conductive
Elastomer Materials..................................................................................... 131
5.3.1 Conduction Mechanism and Process Parameters......................... 131
5.3.2 Appearance Properties and Performance Evaluation................... 133
5.3.2.1 Physical and Mechanical Properties............................. 133
5.3.2.2 Electrical Properties..................................................... 135
5.3.2.3 Thermal Properties....................................................... 137
5.4 Conductive Elastomer Gasket Design Guideline......................................... 137
5.4.1 Flange Joint Geometry and Unevenness....................................... 138
5.4.2 Applied Clamping/Compressive Force.
and Deformation Range................................................................ 139
5.4.3 Gasket Profile and Materials Selection......................................... 141
5.4.4 Flange Materials and Joint Surface Treatment............................. 145
5.5 Conductive Elastomer Gasket Fabrication................................................... 146
5.5.1 Extrusion....................................................................................... 146
5.5.2 Molding......................................................................................... 147
5.5.3 Form-in-Place and Screen Printing............................................... 148
5.5.4 Reinforced Shielding Gaskets with Oriented Wires and.
Metal Meshes................................................................................ 149
5.6 Conductive Elastomer Gasket Installation and Application........................ 149
5.7 Comparable Flexible Graphite Gaskets....................................................... 152
5.7.1 Flexible Graphite and Its Properties............................................. 153
5.7.2 Fabrication and Application of Flexible Graphite Gaskets........... 155
5.8 Summary...................................................................................................... 157
References............................................................................................................... 157
Chapter 6 Conductive Foam and Ventilation Structure................................... 159
6.1 Introduction.................................................................................................. 159
6.2 Waveguide Aperture and Ventilation Panel................................................. 159
6.2.1 Waveguide Aperture and Its Design............................................. 160
6.2.2 Materials Selection and Fabrication Options................................ 163
6.3 Conductive Foam and Integral Window Structure...................................... 165
6.3.1 Conductive Plastic Foam and Vent Panels.................................... 165
6.3.2 Integral EMI Window Structure................................................... 168
6.4 Metallized Fabrics and Fabric-over-Foam................................................... 169
6.4.1 Metallized Fabrics......................................................................... 170
6.4.2 Fabric-over-Foam.......................................................................... 171
6.5 Summary...................................................................................................... 175
References............................................................................................................... 175
Chapter 7 Board-Level Shielding Materials and Components........................ 177
7.1 Introduction.................................................................................................. 177
7.2 Board-Level Shielding Design and Materials Selection.............................. 178
7.2.1 Basic Principles of Board Circuit EMC Design............................ 178
7.2.1.1 PCB Layout................................................................... 178
7.2.1.2 Power Decoupling......................................................... 179
7.2.1.3 Trace Separation........................................................... 179
7.2.1.4 Grounding Techniques.................................................. 180
7.2.1.5 Chassis Construction and Cabling................................ 180
7.2.2 Board-Level Shielding Design with Proper.
Materials Selection........................................................................ 181
7.3 Board-Level Shielding Components and Their.
Manufacturing Technology.......................................................................... 185
7.3.1 Metal Cans.................................................................................... 186
7.3.1.1 Single-Piece Shielding Cans......................................... 186
7.3.1.2 Two-Piece Cans............................................................ 189
7.3.1.3 Multilevel Shielding and Multicompartment Cans....... 190
7.3.2 Metal-Coated Thermoform Shields.............................................. 190
7.3.2.1 snapSHOT Shield.......................................................... 191
7.3.2.2 Form/Met Shield........................................................... 192
7.3.2.3 Formable Shielding Film.............................................. 196
7.4 Conductive Coating Methods Used for EMI Shielding Components.......... 196
7.4.1 Electroplating................................................................................ 197
7.4.1.1 Electroless Plating......................................................... 197
7.4.1.2 Electrolytic Plating....................................................... 198
7.4.1.3 Tin Plating and Tin Whisker Growth in EMI
Shielding Systems......................................................... 199
7.4.1.4 Immersion Surface Finishes.........................................202
7.4.2 Conductive Paints..........................................................................204
7.4.3 Vapor Deposition...........................................................................205
7.4.4 Conductive Coating Application and Design.
Consideration for EMI Shielding..................................................206
7.5 Board-Level Shielding with Enhanced Heat Dissipating............................207
7.5.1 Minimizing EMI from Heat Sinks................................................207
7.5.2 Combination of Board-Level Shielding.
and Heat Dissipation.....................................................................207
7.5.3 Thermal Interface Materials (TIMs) for Thermal-Enhanced.
Board-Level Shielding...................................................................208
7.6 Summary...................................................................................................... 211
References............................................................................................................... 212
Chapter 8 Composite Materials and Hybrid Structures.
for EMI Shielding............................................................................ 215
8.1 Introduction.................................................................................................. 215
8.2 Knitted Wire/Elastomer Gaskets................................................................. 215
8.2.1 Fabrication Process and Materials Selection................................ 216
8.2.2 Knitted Wire Gasket Performance................................................ 218
8.2.3 Typical Gasket Types and Mounting Methods.............................. 219
8.3 EMI Shielding Tapes.................................................................................... 221
8.4 Conductive Fiber/Whisker Reinforced Composites....................................224
8.4.1 Materials Selection and Process.
of Conductive Composites.............................................................225
8.4.2 Carbon Fiber/Whisker Reinforced Materials...............................226
8.4.3 Metal Fiber/Whisker Reinforced Composites..............................227
8.4.4 Nanofiber Reinforced Polymer Composites..................................229
8.5 Hybrid Flexible Structures for EMI Shielding.............................................230
8.6 Electroless Metal Deposition for Reinforcements.
of Composite Shielding Materials................................................................ 231
8.7 Summary......................................................................................................234
References...............................................................................................................234
Chapter 9 Absorber Materials..........................................................................237
9.1 Introduction..................................................................................................237
9.2 Microwave Absorber Materials....................................................................238
9.2.1 Resonant Absorbers.......................................................................240
9.2.1.1 Dallenbach Tuned Layer Absorbers..............................240
9.2.1.2 Salisbury Screens.......................................................... 241
9.2.1.3 Jaumann Layers............................................................242
9.2.2 Graded Dielectric Absorbers: Impedance Matching....................242
9.2.2.1 Pyramidal Absorbers....................................................242
9.2.2.2 Tapered Loading Absorbers..........................................243
9.2.2.3 Matching Layer Absorbers...........................................244
9.2.3 Cavity Damping Absorbers...........................................................244
9.3 Anechoic Chambers.....................................................................................245
9.3.1 Antennas........................................................................................245
9.3.2 Absorber Materials Used in Anechoic Chambers.........................246
9.4 Dielectric Materials for Absorber Applications...........................................246
9.5 Electromagnetic Wave Absorbers................................................................249
9.6 Absorbing Materials Selection and Absorber Applications......................... 251
9.6.1 Absorbing Materials and Absorber Types.................................... 251
9.6.2 Applications.................................................................................. 252
9.6.2.1 Military......................................................................... 252
9.6.2.2 Commercial................................................................... 253
9.7 Summary...................................................................................................... 253
References...............................................................................................................254
Chapter 10 Grounding and Cable-Level Shielding Materials........................... 257
10.1 Introduction.................................................................................................. 257
10.2 Cable Assembly and Its EMI Shielding Design........................................... 257
10.3 Cable-Level Shielding Materials.................................................................. 261
10.3.1 Metallic Shielding......................................................................... 261
10.3.2 Conductive Heat–Shrinkable Shielding........................................263
10.3.3 Ferrite Shielding Materials...........................................................264
10.4 Bonding and Grounding............................................................................... 267
10.4.1 Bonding.........................................................................................268
10.4.2 Grounding.....................................................................................269
10.4.2.1 Shields Grounded at One Point..................................... 270
10.4.2.2 Multigrounded Shields.................................................. 271
10.4.2.3 Hybrid Grounding......................................................... 271
10.5 Summary...................................................................................................... 271
References............................................................................................................... 272
Chapter 11 Special Shielding Materials in Aerospace.
and Nuclear Industries..................................................................... 275
11.1 Introduction.................................................................................................. 275
11.2 Lightweight Shielding Materials for Aerospace Applications..................... 275
11.2.1 Lightweight Radiation Shielding Material.................................... 276
11.2.2 Fiber Reinforced Composite Materials.........................................277
11.2.3 Nanomaterials............................................................................... 279
11.2.4 Foam Structures............................................................................280
11.3 Radiation Shielding for Space Power Systems............................................ 281
11.3.1 Neutron Shielding Design and Materials Selection......................282
11.3.2 Shielding Materials for Earth Neighborhood Infrastructure........282
11.3.3 Active Electromagnetic Shielding for Space Radiation................283
11.3.4 Optimization of Space Radiation Shielding..................................285
11.4 Nuclear Shielding Materials........................................................................286
11.5 Summary......................................................................................................289
References............................................................................................................... 291
Chapter 12 Perspectives and Future Trends.......................................................293
12.1 Introduction..................................................................................................293
12.2 Early Design-in for EMC and Optimal Design of EMI Shielding..............293
12.3 Advanced Materials Selection for EMI Shielding.......................................297
12.3.1 Materials Selection for EMI Shielding Enclosure/Cover/
Barrier...........................................................................................298
12.3.2 EMI Gasketing Material Selection................................................299
12.3.3 Other Shielding Materials Selection............................................. 301
12.4 Future Trends and Applications...................................................................302
12.4.1 EMI Shielding Design Techniques................................................302
12.4.2 Integrated Circuit-Level Shielding................................................303
12.4.3 Printed Circuit Board (PCB)-Level Shielding..............................305
12.4.3.1 Lightweight Shields for PCB-Level Shielding..............305
12.4.3.2 Mold-in-Place Combination Gaskets for
Multicompartment Shields............................................306
12.4.3.3 Rotary Form-in-Place Gaskets......................................307
12.4.4 EMI Shielding Modules or Enclosures.........................................308
12.4.4.1 Conductive Foam with Z-Axis Conductivity................308
12.4.4.2 Dent-Resistant Vent Panels...........................................309
12.4.4.3 Nanocomposite Shielding Materials.............................309
12.4.4.4 Ultrasoft Sculpted Fabric-over-Foam........................... 310
12.4.5 Interconnecting Level Shielding................................................... 310
12.4.6 EMI Control or Immunity by Software........................................ 311
12.5 Summary...................................................................................................... 311
References............................................................................................................... 312
Index ...................................................................................................................... 315

:51bb谢谢楼主！

楼主最近发布了好多经典好书，非常感谢对社区的大力支持

thank you for your book

感谢楼主分享

顶一下，谢谢分享！

謝謝樓主的用心分享^^:19bb:29bb

:16bb:16bb

謝謝樓主的用心分享

thank you very much

thank you very much

太感謝樓主分享拉

为什么没下下来。。。郁闷中。。。等待中。。。。

理论性比较强

非常感恩
下載來學習

谢谢楼主分享了啊

謝謝樓主的無私分享^^
3Q~~

Thanks master for the reference material, and it's helpful EMI/EMC engineer.

thank you so much for sharing a nice book!

多谢分享{:7_1234:}

回复 masterchen 的帖子

这个必须顶……

謝謝分享！

谢谢分享

确实是非常好的书

太棒了，谢谢老大，前一些日子还在犯愁呢，终于在这里找到这本书了。:16bb

谢楼主分享

very thanks for your sharing!

学习了！！！！！！

材料是国人的痛啊！

感谢分享！