High temperature inorganic paint

Abstract

An inorganic paint suitable for harsh environments, and particularly suitable as a thermal control coating for spacecraft, includes a mixture of 50% or more dry weight barium titanate (BaTiO.sub.3) pigment powder with a binder of an alkali metal silicate such as potassium silicate K.sub.2 SiO.sub.3 or sodium silicate Na.sub.2 SiO.sub.3. Instead of alkali metal silicate binder, a glass frit may be used, which when fused binds the pigment to the substrate. The coefficient of thermal expansion of the pigment is about 12.times.10.sup.-6 /.degree.C. The coefficient of thermal expansion of the paint is moved toward the coefficient of expansion of the substrate by addition of a filler consisting of magnesia to increase the paint's coefficient of expansion, or alumina and/or silica to decrease the paint's coefficient of expansion. The paint survives harsh environments, ultraviolet radiation and a fluence of charged particles, while maintaining a low solar absorptance and high thermal emittance. Ceria may be added to the paint to reduce formation of color centers. The paint may be extruded onto a vaporizable transfer medium to form a tape.

Dependencies are inferred from the claim text.