Ceramic coatings for high-temperature protection of steel

Abstract

A new type of ceramic coating for the protection of low-carbon steel in high-temperat ure service was d eveloped during the war at the National Bureau of Standards and was used by the Army and Navy on the exhau st system s of certain a ircraft and other vehicles. The out-standing features of these coatings are (a) high resistance to chipping unde r repeated thermal hock, (b) protection of the metal against ox idation during prolonged expo. ure at tempera-t ures up to about 1,250° F , (c) freedom from the crac kin g and blistering produced in con-ventional porcelain enamels under comparable conditions of high temperature and severe Lhermal gradients, and (d) a mat surface wh ich does not show high lights and , t herefore, decreases t he visibility .