Abstract
The impedance response under the polarization was measured, and the difference of passive state according to the density under the NaF solution of pure titanium and its alloy was examined from the change in the tracks variously. In addition, the relation to water wettability was considered. The third semicircle that took part directly in the formation of the film both of the impedance tracks of pure titanium and its alloy was seen. Both of the diameter 0.1% in the density is larger than 2.0%, and passive state film on the surface is thicker. In general, it is not easy to get wet from the result of water wettability measurement after the former report is soaked for water by both NaF densities low. It seems that there are some relations from these between the film thickness and water wettability.