Interfacial titanium oxide between hydroxyapatite and TiAlFe substrate.
The interface between nano-crystalline hydroxyapatite (HA) thin films and a titanium alloy (Ti5Al2.5Fe) has been studied by means of Fourier transform infrared spectrophotometry and X-ray diffraction at grazing incidence. The HA thin films were deposited by radio-frequency magnetron sputtering in low pressure dry argon on substrates kept at low temperature or heated at 550 degrees C. The effect of film treatment by sputtering and annealing in humid air, as a simple, effective way of restoring the crystallinity and stoichiometry of the HA bulk, was studied in correlation with the development of a titanium oxide layer at the film-substrate interface. An interfacial TiO(2 )film grew at the interface during annealing in moist air, while a TiO(2) layer diffused into the HA films when directly sputtered at 550 degrees C. The formation of an interfacial titanium oxide layer was inhibited by the insertion of a crystalline TiN buffer interlayer between the substrate and the HA film. Separately, the mechanical characteristics of the different HA films were monitored by nanoindentation to find out how they had been affected.
Nelea
Valentin
V
National Institute for Lasers, Plasma, and Radiation Physics, PO Box MG-54, Bucharest 77125, Romania.
Morosanu
Constantin
C
Bercu
Mircea
M
Mihailescu
Ion N
IN
D000497:Alloys / Q000032:analysis* / Q000138:chemical synthesis* / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods
D000497:Alloys; D020099:Coated Materials, Biocompatible; C528635:titanium aluminum alloy; C009495:titanium dioxide; D017886:Durapatite; D014025:Titanium