EFFECT OF APPLIED VOLTAGE AND SUBSTRATE PREPARATION ON SURFACE MODIFICATION OF ANODICALLY OXIDIZED TITANIUM

In the present work, anodic oxidation (AO) treatment was used to modify surface of commercially-pure (CP) titanium. C.P-Ti ASTM grade 2 specimens, in two shapes of disc and plate were prepared for this work. Disc titanium specimens were ground, polished and etched, while plate ones just etched. Afterwards anodic oxidation treatment performed in phosphoric acid electrolyte at 100, 200, and 300V. Crystalline structures of the substrate and grown films were evaluated using X-ray diffraction (XRD). Scanning electron microscopy (SEM) micrographs represented that by increasing the applied anodic voltage, the pore size increased, while the number of pores decreased. Energy-dispersive X-ray Spectroscopy (EDS) analysis was performed to assay compositions of the prepared films. Roughness measurement of surface before and after anodic oxidation treatment indicated that etched plate samples had higher surface roughness than disc specimens. Moreover roughness measurements represented that by applying higher voltage during anodic oxidation treatment, surface roughness increased due to arc-generation at high applied voltages, especially for those which anodized at 300V.