Materials Improve EMI Shielding Of Air Filters April 2001 Issue Published Date: April 01, 2001
State-of-the-art materials and design techniques help enhance the EMI/RFI shielding capability of the new Dual EMI air filters. Conductive silver/copper adhesive caulk fully bonds EMI mesh to aluminum filter frames to promote enclosure grounding of EMI noise. This is further enhanced by the addition of EMI nickel/copper metallized fabric wrapped around a neoprene foam gasket. The gaskets can be installed around the perimeter of the filter frame for full conductivity of the framed filter to the enclosure in which it is installed. Dual EMI air filters can now be ordered with chromate and irridite finishes on aluminum components to provide corrosion protection and improved conductivity. Chromate and irridite finishes are particularly important in electronics equipment applications susceptible to corrosion. Unprotected aluminum is subject to corrosion in oxidizing environments, and such corrosion interferes with an air filter’s ability to provide EMI shielding because conductivity of the corroded aluminum parts is reduced.
