摘要 |
<p>Coated ferromagnetic particles are provided which are useful as radar absorbing material (RAM). In particular, ferromagnetic particles such as iron, carbonyl iron, cobalt, nickel, and alloys thereof are provided that have been coated with a protective non-conducting material such as silicon, silicon dioxide, aluminum oxide, and the like. The ferromagnetic particles are coated in a rotating retort containing a gaseous composition that deposits onto or diffuses into the particle. The coated particles of the present invention are particularly suitable for incorporation into RAM coating compositions intended for use in corrosive atmospheres.</p> |