Improving the fretting biocorrosion of Ti6Al4V alloy bone screw by decorating structure optimised TiO2 nanotubes layer

Jiajun Luo, Maryam Tamaddon, Changyou Yan, Shuanhong Ma, Xiaolong Wang, Feng Zhou, Chaozong Liu

Fig. 8. Worn after fretting on drill tapping areas, MA screw a1 and a2, NT screw b1 and b2, SONT screw c1 and c2. MA tapping area has worn heavily, tapping upper areas were also worn (a1 and a2, white arrows). The nanotubes layer lift off on NT tapping areas were more than that on SONT (b1 and c1, b2 and c2), some areas on SONT displayed light grey color (c1 and c2, white arrows).