Radar absorbing materials (RAMs) have been researched since the advent of radar detection technology in the early 1900’s. RAMs are most commonly used when space or weight are restricted such as in stealth coatings on aircraft or ships. Effective RAMs are “lossy” materials which absorb or disperse electromagnetic (EM) radiation in the radio and microwave region (0-30 GHz). Ferrites are a well-researched class of RAMs often employed as films or plates that have narrow, tunable ranges of strong EM absorbance (<-10dB)1 0.5 – 2.0 GHz in breadth. The general formula for ferrites is AFe2O3 where A is a divalent metal such as magnesium, nickel or zinc2; iron can also be substituted with trivalent metals such as cobalt or aluminum3. This presentation will focus on recent research into ferrite doping4, the manipulation of particle size5 and coating composition6,7 to affect the strength and location of ferrite absorption bands.
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