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Non-Metallic Materials
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| Acetal |
Transparent white |
Good electrical properties (400-465 v/mil)
High mechanical properties & rigidity
Fatigue, moisture, gasoline & solvent resistant
Cannot resist: steam, hot waterm or strong bases
Good cold flow resistance
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| Fibre |
Black & Gray |
Extensively used for electrical insulation applications where little moisture is present (150-250 v/mil)
Fair mechanical properties
Can be formed
Good cold flow resistance
Non-magnetic & corrosion resistant
Good thermal conductivity (.25 BTU/hr/ft2/°F/ft)
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| Fiberglass |
Fiberglass |
Laminate of layers of fiberglass mesh with different impregnated resins for different based properties
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G–7, Silicone resin |
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Best heat resistance
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G–9, Heat resistant Melamine resin |
Best mechanical properties of non-metallics
Good electrical insulator particularly under wet conditions (350 v/mil)
Good dimensional stability
Good thermal conductivity for a non-metallic (.29 BTU/hr/ft2/°F/ft)
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G–10, Epoxy resin |
Good dimensional stability
High mechanical strength at room temperature
Good electrical insulator even in humid conditions (400 v/mil)
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G–11, Heat resistant epoxy resin |
Same properties as G-10 at room temperature
Retains 50% of room temperature standard flexural strength when measured at 150°C after 1 hour at 150°C
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| Kapton® |
Red-brown to yellow-orange |
DuPont® trade name for polyimide plastic film
Excellent electrical properties (i.e. 7000 v/mil)
Tensile strength—good(25,000 psi)
Ability to tolerate fairly high temperature (750°F)
Flexible—will not chip, flake or disintigrate under compression loads or in vibratory situations as does Mics
Indicator applications
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| Kel-F |
Transparent |
Electrical grade plastic
Good insulator
Expensive
Due to small sheet size, does not lend itself to automated production methods
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| Mica |
Clear to light brown |
Excellent electrical properties (3,000-6,000 v/mil)
High heat resistance—1050°F
Insulating material
It can chip, flake & disintigrate under compression loads & vibratory situations
Does not lend itself to automated production methods
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| Mylar® |
Translucent |
Extremely good electrical properties (4,000 v/mil)
Insulating material
Maximum thickness—0.014
Less expensive alternate to Kapton for lower temperature applications (300°F)
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| Neoprene |
Black synthetic rubber, 60 shore hardness |
Resilient—tear resistant
Cushioning properties—gaskets
Aircraft applications grade
Good oil resistance
Excellent abrasion & flame resistance
Excellent sealing capabilities
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| Nylatron® |
Charcoal gray |
Polymer Corp. trade name for molybdenum disulfide filled nylon
Electrical properties lessened slightly by the molybdenum disulfide (356 v.mil)
Increased resistance to cold flow and greater bearing qualities as compared to nylon
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| Nylon |
Opaque white |
Good electrical grade material (385 v/mil)
Good bearing properties
Good anti-frictional properties
High strength for a non-metallic
Self-extinguishing—flammability reading of 94V2
Fair cold flow properties
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| Phenolics |
XXXP |
Paper based with phenolformaldehyde resin impregnated
Best moisture resistance for phenolics (0.8%)
Low dielectric losses under severe humidity conditions
Good electrical properties (325 v/mil)
Less expensive than LE & CE, although more difficult to fabricate
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LE |
Fine weave cotton cloth impregnated with phenolformaldehyde resin
Good electrical properties (225 v/mil)
Good moisture resistance (1.3%)
Better machining properties & appearance than CE
Easiest phenolic to fabricate
Not good for primary insulation
Good mechanical properties
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CE |
Coarser weave cottom cloth impregnated with phenolformaldehyde resin
Best mechanical properties of phenolics
Good moisture resistance (1.6%)
Good electrical properties (225 v/mil)
Not good for primary insulation
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Nylon, brown |
Nylon fabric impregnated with phenolformaldehyde resin
All purpose electrical grade
Good for operating temp. below 160°F
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| Polyethylene |
Translucent white |
Common plastic—quite inexpensive
Good electric insulator (460 v/mil)
Good sealing capabilities
Low water absorption rate (0.015%)
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| Teflon® |
Translucent white |
Excellent anti-frictional properties
Good electrical properties (480 v/mil)
Excellent chemical & corrosion resistance
High heat resistance (500°F)
Fair cold flow properties
Very lw water absorption rate (0.005%)
Excellent for low temperature applications
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