THE EFFECT OF ELECTROLYTE COMPOSITIONS ON THE STRUCTURE AND PROPERTIES OF PEO COATINGS ON PURE Ti SUBSTRATE

Abstract

Plasma electrolytic oxidation method was used to form ceramic coatings on pure Ti substrates, using various aqueous solutions of sodium aluminate (15 g/L and 20 g/L, with or without the addition of NaOH, 2 g/L). The PEO process was carried out at constant time and voltage (300 seconds, 200 V). The ceramic coatings obtained by PEO were investigated by SEM, EDS, XRD, XPS and their corrosion behavior has been evaluated. The aim of the study was to understand the role of NaOH in the development of the PEO process and to evaluate the results obtained by short treatments in potentiostatc regime.