RF-Sputtering법에 의한 생체용 Ti합금의 전기화학적 특성에 미치는 ZrN코팅 효과

Abstract

In order to investigate the electrochemical characteristics of ZrN coated Ti-Nb alloys by using RF-sputtering method, the Ti containing Nb up to 3.0 wt%, 20.0 wt% and 40.0 wt% was melted by using a vacuum furnace and then homogenized for 24 hrs at 1050℃. The samples were cut and polished for corrosion test and RF coating. The specimens were coated with ZrN having 600 ㎛ order thickness, respectively, by RF- magnetron sputtering method. The microstructures were observed by using OM and FE-SEM. The corrosion behaviors were investigated using potentiostat (EG&G Co, 263A, USA) in 0.9% NaCl solution at 36.5 ± 1℃ and corrosion surface was observed using OM, FE-SEM and EDX. The results are as follows : 1.Ti alloy containing 3 wt%, 20 wt% and 40 wt% Nb showed α, α + β and β phase, respectively. 2.The current density of Ti-40 wt% Nb alloy was lower than those of other alloy in the 0.9% NaCl and corrosion potential of Ti-40 wt% Nb alloy was higher than those of Ti-3 wt% Nb and Ti-20 wt% Nb alloys. 3.The cosrrosion resistance of Ti-40 wt% Nb was higher than those of Ti-3 wt% Nb and Ti-20 wt% Nb alloy in the 0.9% NaCl solution. 4.The corrosion potential, passive film breakdown potential and repassivation potential of ZrN coated Ti-Nb alloy increased with increasing Nb content but the critical anodic current density at active region and the current density at passive region decreased. These results suggest that, the ZrN coated Ti-Nb alloy is a good corrosion resistance for dental implant compared with non-coated Ti-Nb alloy.