Characterisation of Thin Ceramic Coatings on Metal Substrates

12,5 mol% caO-stabilised zirconia and 18 mol% CeO² -partially stablised zirconia thin film were deposited on 304 stainless steel (s.s.), respectively by means of r.f. magnetron sputtering (physical vapour deposition (PVD) technique) and by dipping in solution of ceramic precursor (sol-gel method). PVD coatings were crystalline (cubic) and [111] textured, whereas dip-coatings, amorphous after deposition, became annocrystalline during a heat treatment at 500°C in vacuum. Despite the completely different microstructure, both types of coating withstood a severe isothermal treatment in air at 850°C up to 15 h, showing a comparable protective action against metal oxidation, provided that their thicknesses were similar.