Testing and Characterization of Nano-structured Alumina Coating Prepared by Different Methods on Ti-6Al-4V alloy (Comparative Study)

Introduction Dental implant had become the most demanded alternative for tooth replacement. This study dealt with modification of Ti-6Al-4V alloy surface to be more compatible with surrounding tissue. Material and method titanium discs were used (2 mm -10 mm in thickness and diameter respectively). The discs were divided in to four groups A) control group of machined discs without surface modification, B) machined discs with physical and chemical vapor deposition (PVD-CVD) of alumina nano particles, C) laser ablated surface with physical and chemical vapor deposition (PVD-CVD) of alumina nano particles and D) machined discs coated with alumina nanoparticles by pulsed laser deposition (PLD). The surface characteristics were studied by scanning electron microscope, x-ray diffraction, atomic force microscope, optical microscope, wettability property (obtained after 15 sec and 30 sec), corrosion resistance (obtaining corrosion rate and tafel plot) and adhesion strength of coated discs. Results SEM images showed nanofeatured alumina of the coated groups with distinct layering of alumina particles and signs of nanowires in LA-PVD-CVD group. XRD analysis shows and pattern of alumina. Contact angle measurements of the four experimental groups in 15 and 30 sec show highly significant difference (Pless than0.01). Corrosion rate shows highly significant difference (Pless than0.01) between metal showed and alumina coated surfaces. Scratch test of the coated layer of the three experimental groups were highly significant difference (Pless than0.01) with the lowest adhesion in PVD-CVD and highest in LA-PVD-CVD. Conclusion An improvement in corrosion resistance of coated surfaces over metal showed. The adhesion strength was improved by with laser ablation in PVD-CVD group while a decrease in wettability of alumina coated surfaces in comparison to uncoated surface.