What are the properties of the different types of shielding coatings?
(All data herein represent typical values for various types of coatings. For specific ratings and details, contact the manufacturer of a specific coating.) * Graphite: Least conductive of the common shielding coatings at 30-50 ohms/square/mil, graphite shielding provides 30-50 dB of protection along a range of 50-450 MHz at 2 mils coating thickness. * Nickel: Excellent durability due to the hardness of the nickel, along with low cost makes nickel a good choice if conductivity between that of copper and graphite is called-for. Conductivity is around 1 ohm/square/mil, which provides as much as 60-65 dB of protection at 2 mils over 5-1,800 MHz. Although not quite as good a conductor as copper or silver, it absorbs more electromagnetic interference on account of its magnetic permeability. * Copper: Probably the most significant commercially used shielding coating material, many copper-based coatings use silver-plated copper fillers to improve resistance to oxidation of the copper. The cond
