Extruded EMI Gaskets - Toptronic A/S

There is an approximate relationshipbetween the force required todeflect a pure elastomer a givenamount, and the hardness of theelastomer. In general, the harderthe elastomer, the greater the forcerequired. In the case of Chomerics’metal particle-filled elastomers,this relationship is much less definite,and in some instances, thesematerials demonstrate deflection/hardness and deflection/thicknessbehavior contrary to that whichwould be anticipated for conventionalelastomer compounds.The inclusion of metal particlesin the elastomer results in a mechanicallystructured material. Thismechanical structure has a markedeffect on the deflection of the elastomerunder compressive loads,and in some instances, hardermaterials deflect more than softermaterials.Compressive load-deflection datafor many popular conductive elastomermaterials and shapes are givenin Figures 1-6. (For “line contact”gaskets, it is more convenient toexpress the load in terms of poundsper linear inch instead of poundsper square inch).For compression-deflection data onother Chomerics gaskets, contactour Applications EngineeringDepartment.Load (lbs / linear inch)Figure 4. Hollow D H 0.156” Wall Thickness 0.45”Load (psi)Figure 5. Sheet Stock 0.032”Load (psi)Deflection vs. Load - 19-05-6419 @ 0.025 in/min.Tested with 1” x 1” Cu probe1298Deflection (%) of Height128513106370121512851350Deflection vs. Load - 40-20-0505 (~30 mil) @ 0.025 in/min.Tested with 1” x 1” Cu probeRecommended Max.Deflection (%)Deflection vs. Load - 40-30-0505 (~60 mil) @ 0.025 in/min.Tested with 1” x 1” Cu probe129863701310128512151298S6305Performance DataRecommended Max.Deflection (%)Figure 6. Sheet Stock 0.062”Chomerics 43