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- an d corrosion-resistant coatings of carbides, nitrides and carbonitrides of cementing metals is promising since it can lead to a flexible surf ace treatment technology combining adaptability with relatively low ca pital and operational costs. In this paper the feasibility of a fluidi zed bed process for the formation of titanium carbide coatings using c hemical-vapour-deposition-based reactions is discussed. The method inv olves a treating agent consisting of a powder mixture of Al2O3 with Fe Ti which is fluidized at elevated temperature with Ar. As an activator of the process NH4Cl was used. The use of explosive hydrogen is avoid ed by the formation of the vapours of the materials to be coated in si tu in the reactor. With this method, adherent and dense coatings of Ti C were applied on various steel grades.