ADHESIVE AND CORROSION-RESISTANT ZIRCONIUM-OXIDE COATINGS ON STAINLESS-STEEL PREPARED BY ION-BEAM-ASSISTED DEPOSITION

To improve the adhesion and corrosion resistance in ceramic and steel systems, zirconium oxide films were deposited on austenitic type 316L stainless-steel substrates by using the ion beam assisted deposition ( IBAD) method, in which ZrO2 evaporation and energetic Ar and/or O-2 io n bombardment at 250 eV were carried out simultaneously. To study the influence of the film thickness on the performance of coatings, thin ( 0.2-0.4 mu m) and thick (2-3 mu m) films were prepared. The film struc ture was investigated by X-ray diffractometry. The adhesion was evalua ted by a tensile pull-off tester, showing that IBAD treatments could p rovide a remarkable potential to enhance the adhesion. The corrosion b ehavior was determined by potentio-dynamic polarization measurements. It was found that excellent corrosion-protection ability of zirconium oxide coatings on stainless steel was achieved after IBAD treatments. The mechanism for explaining the results has been discussed in terms o f the surface observation and X-ray photoelectron spectroscopy studies .