FORMATION OF TIC COATINGS ON STEELS BY A FLUIDIZED-BED CHEMICAL-VAPOR-DEPOSITION PROCESS

The use of a fluidized bed process for the production of hard wear- and corrosion-resistant coatings of carbides, nitrides and carbonitrides of cementing metals is promising since it can lead to a flexible surface treatment technology combining adaptability with relatively low capital and operational costs. In this paper the feasibility of a fluidized bed process for the formation of titanium carbide coatings using chemical-vapour-deposition-based reactions is discussed. The method involves a treating agent consisting of a powder mixture of Al2O3 with FeTi which is fluidized at elevated temperature with Ar. As an activator of the process NH4Cl was used. The use of explosive hydrogen is avoided by the formation of the vapours of the materials to be coated in situ in the reactor. With this method, adherent and dense coatings of TiC were applied on various steel grades.