Advanced Microstructural Study of Suspension Plasma Sprayed Hydroxyapatite Coatings

作者：Podlesak Harry^*; Pawlowski Lech; d'Haese Romain; Laureyns Jacky; Lampke Thomas; Bellayer Severine

来源：Journal of Thermal Spray Technology, 2010, 19(3): 657-664.

DOI：10.1007/s11666-010-9471-6

• hydroxyapatite
• Raman spectroscopy
• suspension plasma spraying
• transmission electron microscopy

Fine, home-synthesized, hydroxyapatite powder was formulated with water and alcohol to obtain a suspension used to plasma spray coatings onto a titanium substrate. The deposition process was optimized using statistical design of 2 (n) experiments with two variables: spray distance and electric power input to plasma. X-ray diffraction (XRD) was used to determine quantitatively the phase composition of obtained deposits. Raman microscopy and electron probe microanalysis (EPMA) enabled localization of the phases in different positions of the coating cross sections. Transmission electron microscopic (TEM) study associated with energy-dispersive x-ray spectroscopy (EDS) enabled visualization and analysis of a two-zone microstructure. One zone contained crystals of hydroxyapatite, tetracalcium phosphate, and a phase rich in calcium oxide. This zone included lamellas, usually observed in thermally sprayed coatings. The other zone contained fine hydroxyapatite grains that correspond to nanometric and submicrometric solids from the suspension that were agglomerated and sintered in the cold regions of plasma jet and on the substrate.

• 出版日期2010-3