Formation of highly oriented hydroxyapatite in hydroxyapatite/titanium composite coating by radio-frequency thermal plasma spraying.
Highly oriented hydroxyapatite (HA) coatings with excellent adhesion were successfully obtained on titanium (Ti) and titanium alloy through a radio-frequency thermal plasma spraying method. The ratio of HA and Ti powders supplied into the plasma was precisely controlled by two microfeeders so as to change the composition from Ti-rich to HA-rich toward the upper layer of the formed coatings. The bond (tensile) strength of the HA/Ti composite coatings was ca. 40-50 MPa. XRD patterns showed that the topmost HA layer of the coatings had an apatite structure with (00l) preferred orientation. The degree of this orientation showed a tendency to increase with an increase in the substrate temperature during spraying.
Inagaki
Masahiko
M
National Institute of Advanced Industrial Science and Technology, Ceramics Research Institute, 2266-98 Anagahora Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan. m-inagaki@aist.go.jp
Yokogawa
Yoshiyuki
Y
Kameyama
Tetsuya
T