Bond Strength of Plasma Sprayed Ceramic Coatings on the Phosphated Steels

P. Pokorny, L. Mastny, V. Sykora, Institute of Chemical Technology Prague, Czech Republic Z. Pala, V. Brozek, Institute of Plasma Physics ASCR v.v.i. Prague, Czech Republic In the presented work, results of adhesion measurements for different systems of steel sheet-phosphate interlayerceramic coating are described. The interlayers were produced by zinc phosphating; alumina, olivine and zirconiasilica-alumina (e.g. eucor) coatings were deposited by water stabilized plasma torch WSP®. However, successful application of the WSP technique depends on the choice of correct deposition parameters preserving the hydrated phosphates from thermal destruction by the molten ceramic particles. For the adhesion measurement ISO 4624 standardized test was used. Corrosion resistivity was measured by polarisation resistance and free corrosion potential in 3 % NaCl solution.