Growth behaviour of anodic oxide film on titanium alloy

Abstract

The growth behaviour of anodic oxide film on titanium alloy in a near neutral electrolyte (C₄H₄O₆Na₂) under pulse galvanostatic method was investigated by scanning electron microscope, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and transmission electron microscopy (TEM). The morphology and roughness of the anodic oxide film were strongly dependent on the anodising time. The result of TEM showed that the oxide film was partly crystallised and mainly composed of amorphous TiO₂. The probable mechanism of film formation had been discussed, which was comprised of three distinctive stages. The growth behaviour of the anodic oxide film was not only vertical but also horizontal. The process of growth was nucleation, agglomeration and coagulation.

Keywords:

• TiO₂
• Sodium tartrate
• Anodic oxidation
• Titanium
• Surface characterisation

Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant no. 51271012) and the Fundamental Research Funds for the Central Universities.