SILICONE
MICARTA®   ACCULAM®   ARBORITE®

SPECIFICATIONS:

U.S. FEDERAL L-P-509A TYPE IV
U.S. MILITARY MIL-P-997D TYPE GSG
NEMA L1-1 GRADE G-7

NATURAL COLOUR:
   WHITE

As with MELAMINE, this thermosetting polymer is not a PHENOLIC, however its method of manufacture, forms, characteristics and applications are also of the "industrial laminate" type. The predominant difference between SILICONE and the other laminates is the considerably higher temperature resistance that SILICONE offers; almost as high as PTFE. Like the other laminates, a wide variety of fillers can be used to accentuate various properties. But the only important reinforcing medium to us is woven glass fabric. SILICONE reinforced with woven glass fabric, N.E.M.A. Grade G-7, in addition to its good temperature resistance, possess quite good dielectric loss, electrical insulation and arc resistance in humid conditions over a wide range of temperature. With the woven glass fabric, SILICONE has good physical properties but not as high as MELAMINE or Epoxy, but the impact strength of SILICONE is higher. Also, SILICONE possesses quite good flame resistance as well as UV resistance and ozone resistance. Due to its resistance to high temperature and its ability to retain much of its physical strength after prolonged exposure to high temperatures, laminated SILICONE actually has a higher strength-to-weight ratio, at elevated temperatures than do many metals. SILICONE has one of the lowest moisture absorptions of any of the other "industrial laminates". Although affected by concentrated acids and bases, SILICONE is more resistant to these chemicals than PHENOLIC or MELAMINE but not as resistant as Epoxy. Like MELAMINE and Epoxy, the machinability of SILICONE is good; but, as with all other materials reinforced with glass-fibres or fabric, tool-wear, even with carbide inserts, is quite high. Also, high quality finishes are only obtainable with expensive secondary operations. And, the production of glass particulate dusts in machining and grinding operations presents a serious health hazard. With a heavy loading of glass fabric, SILICONES, which are usually non-stick, will bond with polar adhesives.

GENERAL PROPERTIES
  ASTM
test
Woven Fibre-Glass Reinforced
G-7
LW CW
SPECIFIC GRAVITY   D792 1.70 1.70
TENSILE STRENGTH psi D638 23000 18500
TENSILE MODULUS 105 psi D638    
ELONGATION % D638 0.95 0.95
FLEXURAL STRENGTH psi D790 23000 20000
FLEXURAL MODULUS 105 psi D790 14.0 12.0
COMPRESSIVE STRENGTH 10% psi D695 45000 14000
COMPRESSIVE MODULUS 105 psi D695    
HARDNESS rockwell M D785 M100 M100
IMPACT STRENGTH (1/2" x 1/2") ft-lb/inch of notch D256 8.5 7.5
THERMAL EXPANSION 10-5/°F D696 0.55 0.55
HEAT RESISTANCE (continuous in air) °F   465 465
DEFLECTION TEMPERATURE   D648    
@ 264 psi °F   >500 >500
@ 66 psi °F   N/A N/A
DIELECTRIC STRENGTH v/mil D149 350 350
DIELECTRIC CONSTANT   D150 3.2 to 5.0 3.2 to 5.0

PLEASE NOTE:
Values shown in the above table are averages and there will be variances from lot to lot. After selecting a material based upon these values, you must conduct tests specific to your application to be assured the material suits your needs.