Cyclic voltammetry, x-ray photoelectron spectroscopy, secondary-ion-mass spectrometry, and ion-scattering spectrometry examination of zirconium passive film breakdown in the presence of sulfate

摘要: Passive films on zirconia were prepared by potentiodynamic polarization in the presence of a range anions and at various pH values. With sulfate chloride electrolyte we found unique transpassive peaks cyclic voltammograms that appear to be associated with an amorphous-to-crystalline transition subsequent enhanced species transport along resulting grain boundaries. X-ray photoelectron spectroscopy, secondary-ion-mass spectrometry, ion-scattering spectrometry have been used characterize before after passive film breakdown. The breakdown can qualitatively described Enp=Ec+η+Φ+Einh. Where Enp is pitting potential, Ec corrosion potential acidified solution, η necessary obtain current density high enough maintain acidity inside pit, Φ drop Einh contribution from inhibitors present. results these surface studies ...