L PHENOLIC (LINEN BASE / PHENOLIC RESIN)
Material Information
Phenolics are thermoset resins formed by the polymerization of phenol and formaldehyde, which can then be impregnated with cotton canvas or linen, paper, or glass cloth materials to form industrial laminates. Overall, industrial laminates are dense, strong and durable, moisture resistant, lightweight, and will not soften when heat is reapplied. Typically they have high mechanical and insulating properties. Grade L Phenolic is made up of a mixture of phenolic resin and fine weave cotton cloth fabrics. This blend makes Grade L Phenolic more machinable for intricate details than Grade C and CE Phenolic. However, it is not recommended for electrical applications. The linen base provides Grade L Phenolic with a high density and good moisture resistance. The ability to resist moisture makes it ideal for use in humid environments. It is available in plate, rod, and tube. L Phenolic meets MIL-I-24768/15 TYPE FBIApplication
- Fine gears and pinions
- Relay bases
- Radio parts
- Terminal bases
- Terminal strips
- Intricate machined parts
- Radio components
- Spacers
- Bushings
- Rollers
Properties
- Easy to machine
- High density
- Low moisture absorption
- Low cost
- Good wear resistance
- Good mechanical strength
- Strong and stiff
- High impact and compressive strength
- Excellent moldability/stability
- Good chemical resistance
Specifications
| Physical | Astm Test Method | Paper | Canvas | Linen |
|---|---|---|---|---|
| Density (lb/in^3) | D792 | 0.049 | 0.05 | 0.048 |
| Specific Gravity | D792 | 1.35 | 1.37 | 1.34 |
| Water Absorption @ 24 hours (%) | D570 | 2 | 2.5 | 1.8 |
| Mechanical | ||||
| Tensile Strength (PSI) Lengthwise, Crosswise | D638 | 15,000 and 12,000 | 11,000 and 9,000 | 13,000 and 9,000 |
| Flexural Strength (PSI) Lengthwise, Crosswise | D790 | 16,000 and 13,200 | 17,500 and 15,000 | 22,000 and 16,000 |
| Compressive Strength (PSI) | D695 | 32,000 | 37,000 | 37,000 |
| Flexural Modulus (KPSI) Lengthwise, Crosswise | D790 | 1,100.000 and 900.000 | 1,600,000 and 1,500,000 | 1,600,000 and 1,200,000 |
| Izod Impact (Notched), ft-lb/in Lengthwise, Crosswise | D256 | .65 and .60 | 1.70 and 1.50 | 1.35 and 1.10 |
| Rockwell Hardness | D785 | M100 | M100 | M110 |
| Thermal | ||||
| Coefficient of Thermal Expansion, 10^-5/°F Lengthwise, Crosswise | D696 | .80 and 1.20 | 1.10 and 1.22 | 1.00 and 1.060 |
| Continous Service Temp (Operating), °F | – | 257 | 257 | 285 |
| Thermal Conductivity, BTU-in/hr-ft² °F | C177 | 2.03 | 2.03 | 2.03 |
| Flammability Rating | UL94 | HB | HB | HB |
| Electrical | ||||
| Dielectric Strength, Short Term, (Volts/Mil) @ .125″ Thick | D149 | 750 (XX) | 550 (CE) | 625 (LE) |
| Arc Resistance (sec) | D495 | 110 | 15 | 15 |
| Dielectric Constant at 1 MHz | D150 | 5 | 5 | 6 |
| Dissipation Factor at 1 MHz | D150 | 0.045 | 0.045 | – |
Disclosure: The information contained herein are typical values intended for reference and comparison purposes only. They should NOT be used as a basis for design specifications or quality control. Contact us for manufacturers’ complete material property datasheets. All values at 73°F (23°C) unless otherwise noted.