Method of making a salt-doped metal-coated article having an evanescent electromagnetic detection signature

Abstract

An article comprising a non-conductive substrate having a sub-micron thickness of an oxidizable metal coating thereon, and an oxidation enhancingly effective amount of a salt, e.g., from about 0.005 to about 25% by weight of salt, based on the weight of oxidizable metal, present on the oxidizable metal coating. Also disclosed is a related method of forming such article, comprising chemical vapor depositing the oxidizable metal coating on the substrate, applying the salt by contacting of the oxidizable metal-coated substrate with a salt solution, and drying of the salt solution on the oxidizable metal film to yield the product salt-doped, oxidizable metal-coated substrate article. When utilized in a form comprising fine-diameter substrate elements such as glass or ceramic filaments, the resulting product may be usefully employed as an "evanescent" chaff. In the presence of atmospheric moisture, such evanescent chaff undergoes oxidization of the oxidizable metal coating so that the radar signature of the chaff transiently decays, with the level of salt doping of the oxidizable metal film being variable to achieve a desired functional life and decay rate of the chaff radar signature.

Dependencies are inferred from the claim text.