Degradation of thermal oxide film on pure titanium in an acidic environment containing fluoride
Liwei Wang, Mingtao Wang, Mingyuan Zhong, Xiaoqi Li, Zhongyu Cui
Abstract
Abstract Electrochemical degradation behavior of thermally oxidized pure Ti in the fluoride-containing acidic environments was investigated. Compact TiO 2 oxides with acceptable hardness and superior corrosion resistance are formed through the thermal oxidation at 650 °C for 24 h. Corrosion of the oxidized Ti depends on the oxidation condition and fluoride content, resulting in the various interfacial structures at the oxide/solution and metal/solution interface. Degradation of the oxidized Ti consists of three stages during long-term immersion, while its critical fluoride concentration is increased by 1~2 orders of magnitude, attributed to the high stability of the TiO 2 thermal oxides.