Method of chromizing a workpiece by applying a coating containing chromium particles onto a ceramic carrier, positioning the carrier proximate the workpiece, and heating both carrier and workpiece to diffuse chromium particles into the workpiece

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.