Low Temperature Crystallization and Structural Modification of Plasma-Sprayed Hydroxyapatite Coating with Hydrothermal Treatment

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The effect of autoclaving hydrothermal treatment on the characteristics of plasma-sprayed hydroxyapatite (HA) coatings on the Ti-6Al-4V substrate was investigated. The heating temperatures were 100°C, 150°C and 200°C with ambient saturated steam pressure in an autoclave. On the basis of quantitative analysis of crystallinity using x-ray diffraction (XRD), hydrothermal treatment was found to be effective for increasing the crystallinity and phase purity of the HA coatings. The prominent and sharp OH− and PO4 3− peaks detected from x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra demonstrate a superior crystallized integrity of hydrothermal-treated HA coatings through the incorporation of water vapor. Moreover, the significant presence of OH− peak in XPS spectra represents a replenishment of water molecules which tends to reduce the dehydroxylation state of as-sprayed HA coatings. From the observation of microstructures, crystallized HA was found to diminish the spraying defects of hydrothermal HA coating layers, and finely-crystallized HA crystals, with a Ca/P atomic ratio of 1.67, were observed through transmission electron microscopy (TEM). Hydrothermal treatment could induce a low-temperature crystallization process, and the saturated steam pressure is thought to be a factor which reduces the activation energy and accelerates the HA crystallization. Experimental evidence confirmed that the ambient saturated steam pressure plays an important role in lowering heating temperatures and promoting HA crystallization.

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Advanced Materials Research (Volumes 15-17)

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147-152

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February 2006

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© 2007 Trans Tech Publications Ltd. All Rights Reserved

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[1] E. Munting, M. Verhelpen, F. Li and A. Vincent, in: T. Yamamuro, L.L. Hench and J. Wilson (Eds. ): CRC handbook of bioactive ceramics II (CRC Press Inc., Florida, 1990) pp.143-148.

Google Scholar

[2] B.C. Wang, E. Chang, T.M. Lee and C.Y. Yang: J Biomed. Mater. Res. Vol. 29 (1995), p.1483.

Google Scholar

[3] K.A. Gross and C.C. Berndt: J Biomed. Mater. Res. Vol. 39 (1998), p.580.

Google Scholar

[4] C.Y. Yang, B.C. Wang, E. Chang and B.C. Wu: J Mater. Sci: Mater. Med. Vol. 6 (1995), p.258.

Google Scholar

[5] C.Y. Yang, R.M. Lin, B.C. Wang, T.M. Lee, E. Chang, Y.S. Hang and P.Q. Chen: J Biomed. Mater. Res. Vol. 37 (1997), p.335.

Google Scholar

[6] H. Li, K.A. Khor and P. Cheang: Biomaterials Vol. 23 (2002), p.2105.

Google Scholar

[7] Y.P. Lu, Y.Z. Song, R.F. Zhu, M.S. Li and T.Q. Lei: Appl. Surf. Sci. Vol. 206 (2003), p.345.

Google Scholar

[8] K. A. Gross, V. Gross and C.C. Berndt: J Am. Ceram. Soc. Vol. 81 (1998), p.106.

Google Scholar

[9] C.F. Feng, K.A. Khor, E.J. Liu and P. Cheang: Scripta Mater. Vol. 42 (2000), p.103.

Google Scholar

[10] C.W. Yang, T.M. Lee, T.S. Lui and E. Chang: Mater. Sci. Eng. C Vol. 26 (2006), in press.

Google Scholar

[11] J. Chen, W. Tong, Y. Cao, J. Feng and X. Zhang: J Biomed. Mater. Res. Vol. 34 (1997), p.15.

Google Scholar

[12] Y. Yang, K.H. Kim, C.M. Agrawal and J.L. Ong: J Dent. Res. Vol. 82 (2003), p.833.

Google Scholar

[13] C.W. Yang, T.S. Lui, T.M. Lee and E. Chang: Mater. Trans. Vol. 45 (2004), p.2922.

Google Scholar

[14] S. Koutsopoulos: J Biomed. Mater. Res. Vol. 62 (2002), p.600.

Google Scholar

[15] A. Boyd, M. Akay and B.J. Meenan: Surf. Interface Anal. Vol. 35 (2003), p.188.

Google Scholar

[16] C. Chang, J. Huang, J. Xia and C. Ding: Ceram. Inter. Vol. 25 (1999), p.479.

Google Scholar

[17] L.Y. Huang, K.W. Xu and J. Lu: J Mater. Sci.: Mater. Med. Vol. 11 (2000), p.667.

Google Scholar

[18] C. Liu, Y. Huang, W. Shen and J. Cui: Biomaterials Vol. 22 (2001).

Google Scholar