Abstract:Hydroxyapatite(HAP, Ca₁₀(PO₄)6(OH)₂) is one of the quite important bone implant materials. The hydroxyapatite crystals were synthesized under hydrothermal condition. The specimen was verified to be HAP crystal by the X-ray powder diffractometry(XRD). Then the specimen was distinguished single crystal from polycrystal by the use of the transmission electron microscope(TEM). The diffraction pattern of the specimen is neatly arranged diffraction spots, that verified the crystals were single crystals. The interplanar distance d calculated from diffraction spot is coincided with that of HAPs JCPDS card. Moreover, crystal face angles calculated from crystal face index are coincided with the values by measuring on the pattern. The HAP crystals are needle-like in shape with about 3μm in diameter and 180μm in length. Most of the crystals are separate whiskers. Their length/diameter ratio ranges from 40 to 100. The average ratio is about 60.

Key words:  hydroxyapatite; single crystal; hydrothermal method; diffraction pattern