Evaluation of nanostructured carbonated hydroxyapatite coatings formed by a hybrid process of plasma spraying and hydrothermal synthesis.
Carbonated hydroxyapatite (CHA) coatings on a titanium alloy were prepared by hydrothermal synthesis of precursors plasma-sprayed with brushite as a raw powder. The structures, residual stresses, and bond strengths of the precursors and CHA coatings were investigated. The results showed that the sprayed precursors consisted of beta-Ca(2)P(2)O(7), alpha-Ca(3)(PO(4))(2), and CaHPO(4), whereas the CHA coatings exhibited a unique phase construction, nanostructured and needle-like crystals, and a fairly low tensile residual stress. The bond strength of a CHA coating 200 microm thick was 15 MPa, equivalent to that of a plasma-sprayed hydroxyapatite (HA) coating. The evaluation of the CHA coatings was performed together with that of plasma-sprayed HA coatings immersed in distilled water. The dissolution and bond-strength degradation of the CHA coatings were much lower than those of the plasma-sprayed HA coatings.
Han
Yong
Y
State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China. pethany@xjtu.edu.cn
Xu
Kewei
K
Montay
Gillaume
G
Fu
Tao
T
Lu
Jian
J
D002244:Carbon / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis* / Q000737:chemistry; D006882:Hydroxyapatites / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
D020099:Coated Materials, Biocompatible; D006882:Hydroxyapatites; D002244:Carbon; D014025:Titanium