Pixel International Conferences

Surface modification techniques play an important role in materials science and engineering. The anodic oxidation of aluminum is a well-known example to demonstrate the improved corrosion resistance [1] and is therefore used in science classes regularly. The same process can also be applied to titanium with the benefit that the oxide layers cause an intense coloring due to interference effects [2,3]. This can be used in classes to establish a simple correlation between the observed color and the thickness of the oxide layer. Herein, we present simple electrochemical experiments for the synthesis and characterization of titanium dioxide layers for educational purposes. They can be obtained by a facile setup using commercially available titanium sheets and a mildly acidic aqueous electrolyte within seconds or minutes. By varying the synthesis parameters (e.g. voltage, electrolyte, reaction time), morphology and thickness of these layers can be controlled. In our contribution, we explain the relation between observed color and thickness using a simple model. Further aspects will cover educational experiments using digital data logging and characterization methods like scanning electron microscopy. Furthermore, the industrial relevance of titanium surface modification for improved properties like corrosion resistance, hardness of materials, and electrical conductivity is shown.

Keywords: surface modification, anodic oxidation, interference

References:

[1] Bouchama, L. et al. (2013). Enhancing aluminium corrosion resistance by two-step anodizing process. Surface and Coatings Technology, 235, 676-684.

[2] Karambakhsh, A., Afshar, A., Ghahramani, S. & Malekinejad, P. (2011). Pure Commercial Titanium Color Anodizing and Corrosion Resistance, Journal of Materials Engineering and Performance, 20(9), 1690-1696.

[3] Napoli, G., Paura, M., Vela, T. & Di Schino, A. (2018). Colouring Titanium Alloys by Anodic Oxidation, Metalurgija, 57, 111-113.