Abstract: An improved method for aluminizing a ferritic material by forming an aqueous aluminum slurry composition, applying the aqueous aluminum slurry composition to the ferritic material to form a coating, adding a halide activator to the coated ferritic material and heating the coated ferritic material to a temperature of about 1275.degree. F. to about 1300.degree. F. for approximately 24 hours. The use of the lower temperature thermal cycle minimizes the change in the mechanical properties of a steel substrate.

Abstract: A method for diffusion coating a workpiece with chromium (Cr), silicon (Si), aluminum (Al), or boron (B) by placing coated ceramic alumino-silicate fibers next to the workpiece and heating to diffuse the diffusion coating into the workpiece. A ceramic carrier is fabricated from the alumino-silicate fibers woven into a predetermined fashion. Alternately the ceramic carrier may be an elongated ceramic carrier. The aqueous diffusion coating composition is applied to the ceramic carrier and then the ceramic carrier is heated at a temperature of between about 150.degree. F. to 250.degree. F. prior to positioning the ceramic carrier proximate a surface of the workpiece. The ceramic carrier and the workpiece are subjected to an elevated temperature in a controlled environment for a sufficient time to cause at least one diffusion element to diffuse into the workpiece to provide the diffusion coating for the external, the internal, or both surfaces of the workpiece.

Abstract: An improved method of diffusion coating a workpiece, such as ferritic tubing employing a ceramic carrier provided with a diffusion composition. The diffusion composition includes a diffusion element such as chromium, silicon, aluminum, and boron. The carrier is subjected to an elevated diffusion temperature in a controlled environment to diffusion coat either the external or internal surface of the workpiece.