Phase transformation of plasma-sprayed hydroxyapatite coating with preferred crystalline orientation.

摘要: Abstract Highly oriented hydroxyapatite coatings (HACs) were obtained on titanium substrates through a radio-frequency thermal plasma spraying (TPS) method. XRD patterns showed that the HACs had crystallites with [0 0 l] preferred orientation vertical to coating's surface. results also indicated tetracalcium phosphate in as-sprayed HAC (1 0 0) direction. peaks corresponding phosphate, tricalcium and calcium oxide absent after heat hydrothermal treatment. The degree of was influenced little by such post-heat treatments. Considering crystallographic relationship between HA formed heat-treated HAC, these indicate as-prepared transformed topotaxially into during TEM SEM analyses highly conducted. characteristic lamellar structure TPS deposits observed cross-sections HAC. A prismatic texture magnified images. observation 200–800-nm-wide splats, their longitudinal axis vertically SAD corresponded [0 0 1] zone crystal.