Hydroxyapatite coatings deposited on titanium substrate by pulsed laser deposition

Hydroxyapatite (HA) coatings were deposited on titanium substrate by means of pulsed laser deposition (PLD) with Nd:YAG laser. Deposition was carried out at 20 Pa of water vapor atmosphere and at room temperature. An Nd:YAG laser operating at a repetition rate of 10 HZ was used for deposition. In above deposition condition, the HA coatings deposited by PLD at room temperature are amorphous phase, and Ca/P ratio in HA coatings decreases with increasing water vapor pressure. The amorphous HA coatings were recrystallized after hydrothermal treatment at 190 degrees C for 10 h. The bonding strength of the HA coating to the Ti substrate is up to 19.6 MPa. The structure and morphology of samples were characterized by X-ray diffraction, Fourier transform infrared reflection specterophotometry, scanning electron microcopy. The atomic ration of Ca and P was semiquantitatively determined by electron probe micro analyzer.