Sol-Gel Derived TiO₂ Coating on Hydrothermally Roughened NiTi Alloy

Abstract:

Nearly equiatomic NiTi alloy is hydrothermally treated in a urea solution at 150°C to form nanostructures at the surface, with the aim to improve the structural quality of sol-gel deposited TiO2 film. Nanosheets film of ammonium titanate is formed on NiTi alloy after 8 h hydrothermal treatment, and the sol-gel TiO2 film on it is smooth and crack-free. Anatase TiO2 films consisting of nanoparticles and granular deposits are formed on the NiTi samples hydrothermally treated for 16 h and 24 h. The subsequently deposited TiO2 films have short cracks, because the nanostructured films can not completely balance volume shrinkage of the gel film during the drying and heat treatment processes. Water contact angles of the duplex treated NiTi samples increase during ageing in air, but are all reduced to below 10 after 2 h UV irradiation treatment. Potentiodynamic polarization tests in 0.9% NaCl solution indicate that the duplex treated NiTi samples have much better corrosion resistance than the polished one.

• Periodical: Advanced Materials Research (Volume 668)
• Pages: 830-834
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.668.830
• Online since: March 2013
• Authors: Bing Hui Dong, Chen Zhang, Zafer Alajmi, Ke Yong Wang, Tao Fu
• Keywords: Corrosion, Hydrophilicity, Hydrothermal, NiTi Alloy, Sol-Gel, TiO₂

References

[1] J.X. Liu, D.Z. Yang, F. Shi and Y.J. Cai: Thin Solid Films Vol. 429 (2003), p.225.

[2] K.Y. Chiu, M.H. Wong, F.T. Cheng and H.C. Man: Appl. Surf. Sci. Vol. 253 (2007), p.6762.

[3] T. Fu, B.G. Liu, Y.M. Zhou and X.M. Wu: J Sol-Gel Sci. Techn. Vol. 58 (2011), p.307.

[4] Y. Chun, D.S. Levi, K.P. Mohanchandra and G.P. Carman: Mater. Sci. Eng. C Vol. 29 (2009), p.2436.

[5] M.H. Wong, F.T. Cheng and H.C. Man: Scripta Mater. Vol. 56 (2007), p.205.

[6] T. Fu, X.M. Wu, F. Wu, M. Luo, B.H. Dong and Y. Ji: Trans. Nonfer. Metals Soc. China Vol. 22 (2012), p.1661.

[7] J.G. Yu, X.J. Zhao, J.C. Du and W.M. Chen: J Sol-Gel Sci. Techn. Vol. 17 (2000), p.163.

[8] E. Hosono, H. Matsuda, I. Honma, M. Ichihara and H. Zhou: Langmuir Vol. 23 (2007), p.7447.

[9] J.M. Li, Y.X. Yu, Q.W. Chen, J.J. Li and D.S. Xu: Crystal Growth Design Vol. 10 (2010), p.2111.

[10] J.C. Chang, W.J. Tsai, T.C. Chiu, C.W. Liu, J.H. Chao and C.H. Lin: J. Mater. Chem. Vol. 21 (2011), p.4605.

[11] T. Ueno, M. Yamada, T. Suzuki, H. Minamikawa, N. Sato, N. Hori, et al: Biomater. Vol. 31 (2010), p.1546.

[12] A. Mills and M. Crow: International J. Photoenergy Vol. 2008 (2008), p.470670.

[13] Y.G. Han, G. Wu, M. Wang and H.Z. Chen: Nanotechn. Vol. 20 (2009), p.235605.