|Title||Development of hydroxyapatite coatings by solution precursor plasma spray process and their microstructural characterization
Posted by Rolando Candidato Jr.
|Authors||Rolando T. Candidato Jr., PaweÃ Â SokoÃ Âowski, Lech PawÃ Âowski, Gisele Lecomte-Nana, Catalin Constantinescu and Alain Denoirjean|
|Journal||Surface & Coatings Technology|
|Abstract||Solution precursor plasma spraying (SPPS) is a promisingmethod of obtaining coatingswith unique microstructural features. The present study reports about the development of hydroxyapatite (HA) coatings by SPPS using water-based calcium-phosphate solution and about the analyses of their microstructure. X-ray diffraction (XRD) analysis showed that HAwas the major crystal phase of the coatings, being present in the range from95% to 98%. The coatings of greater HA content were obtained while spraying using shorter spray distance. The coating crystallinity ranges from24% to 69% depending on the temperature at deposition. An increase of the temperature results in greater crystallinity. The obtained coatings' microstructuresmay be described by dome-like surface and by the columnar-like cross-section when using precursor with low concentration. The use of concentrated solution precursor results in cauliflower-like structures composed of agglomerated fragmented shells and fine spherical particles. The possible phenomena occurring in droplets in contact with the plasma jet and the coating buildup mechanisms were tentatively explained.|
|Index terms / Keywords||Hydroxyapatite coatings Solution precursor plasma spraying Crystallinity Percent purity Coating microstructures|