Extruded EMI Gaskets - Toptronic A/S

Heat Transfer FundamentalsExtrusion Product GuideIntroduction•••AvailabilityDesign FlexibilityCost EffectivenessProven Performance•…just four of the reasons whyconductive elastomer gaskets areso often the right EMI shieldingsolution!Once used mainly to shield criticaldefense and aerospace electronicsystems, Chomerics’ conductiveelastomer extrusions have alsobecome the progressive choice forpackaging designers of consumer,telecommunications, business andindustrial equipment, automotive,medical devices and much more.Conductive elastomers are reliableover the life of the equipment.The same gasket is both an EMIshield and an environmental seal.Elastomer gaskets resist compressionset, accommodate low closureforce, and help control airflow.They’re available in corrosion-resistantand flame-resistant grades.Their aesthetic advantages areobvious.Almost any elastomer profile can beextruded, with modest tooling costsand short lead times for eitherprototypes or large orders. Chomericscan take a customer-supplieddesign and deliver extrudedparts typically in just a few weeks.Chomerics offers hundreds of standardextrusions. Extrusions arealso readily lathe-cut into washers,spliced, bonded, kiss-cut, or evendie-cut to reduce the installationlabor and conserve material, providinga cost-effective alternative toother methods of EMI shielding andenvironmental sealing.Attachment methods range fromfriction-fit strategies to pressure-sensitiveadhesive (PSA), andinclude clip-mount options.CHO-SEAL ® & CHO-SIL ®CONDUCTIVE ELASTOMERSSince 1961, Chomerics has inventedand extended virtually every aspectof conductive elastomer materialstechnology – from the earliestsilver- and silver/copper-filledsilicones to the latest and morecost-effective silver/aluminum andnickel/graphite composites. Todaywe offer the most comprehensiveselection and highest quality productsavailable anywhere.Each conductive elastomer consistsof silicone, fluorosilicone or EPDMbinder with a filler of pure silver,silver-plated copper, silver-platednickel, silver-plated aluminum,silver-plated glass, nickel-platedgraphite or conductive graphiteparticles.The development of these compositesis the result of decades ofresearch and testing, both in thelaboratory and in the field. Ourproprietary filler powder technologyallows us to carefully control thecomposition, size and morphologyof the conductive particles. Theirprecise, uniform dispersion withinthe polymeric binders producesmaterials with stable and consistentelectrical and physical properties.Chomerics’ conductive elastomersfeature excellent resistance tocompression set over a wide temperaturerange, resulting in yearsof continuous service. In addition toEMI shielding, these materials willprovide an environmental or pressureseal, if required.Our Applications EngineeringDepartment is ready to assist withmaterial selection and gasketdesign. We welcome your inquiry!MATERIAL SELECTIONChomerics’ array of conductiveelastomers offers true flexibility inselecting the appropriate materialfor a specific application on the basisof cost and level of performancerequired. Price varies directly withshielding performance.In general, certain types of Chomerics’conductive elastomersare specified more often for military/aerospaceapplications or forcommercial applications. However,there is a considerable overlap, andour Applications Engineering Departmentwill be pleased to assistyou with product selection.For military/aerospace applications,we recommend that users of conductiveelastomer gaskets specifythat materials meet the requirementsof MIL-DTL-83528 (formerlyMIL-G-83528) and be procured fromMIL-DTL-83528 QPL sources. Toavoid the risk of system EMI or environmentalseal failure, any changein conductive elastomer seal supplier(including MIL-DTL-83528QPL suppliers) should be precededby thorough system qualificationtesting.Commercial Materials:CHO-SEAL 1273, CHO-SEAL S6305,CHO-SEAL 6370**, CHO-SEAL 6315,CHO-SEAL 6372**, CHO-SEAL 6308,CHO-SEAL L6303, CHO-SEAL 1285,CHO-SEAL 1350.Extrusion Product GuideChomerics 5