CHARACTERIZATION OF THIN CERAMIC COATINGS ON METAL SUBSTRATES

12.5 mol% CaO-stabilised zirconia and 18 mol% CeO2-partially stabilise d zirconia thin films were deposited on 304 stainless steel (s.s.), re spectively by means of r.f. magnetron sputtering (physical vapour depo sition (PVD) technique) and by dipping in solution of ceramic precurso r (sol-gel method). PVD coatings were crystalline (cubic) and [111] te xtured, whereas dip-coatings, amorphous after deposition, became nanoc rystalline during a heat treatment at 500 degrees C in vacuum. Despite the completely different microstructure, both types of coating withst ood a severe isothermal treatment in air at 850 degrees C up to 15 h, showing a comparable protective action against metal oxidation, provid ed that their thicknesses were similar.