Sullivan surfaces for carbon substrates are stable to 2300 deg c (4173 deg f) under vacuum. Coating material is impervious to atomic oxygen attack. State of the art coatings for carbon-carbon are limited to 1400 deg c for brief periods. Sullivan mixed surfaces are potentially spall and oxidation resistant after many cycles of prolonged periods at 1900 deg c. Mixing the surface by means of new high energy technology can produce, heretofore, impossible or practical surfaces. Carbon-carbon can be "hard-faced" for abrasion resistance.
