کلیدواژهها
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Calcium deficient hydroxyapatite, Biomimetic, b-TCP, Growth, Nucleation, Sodium silicate, Zirconia toughened alumina
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چکیده
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The present work studied bioactive coatings on the surface of ceramic biomaterials. Zirconia
toughened alumina (ZTA) composites containing 15 mol.-%. Partially stabilised zirconia was
prepared after 1 h sintering at 1550uC. Apatite layers were then coated onto the surfaces of
composites by the biomimetic method using 1?5–2 multiply concentrations of simulated body fluid
(SBF). Before treatment in SBFs, a sodium silicate layer was employed as nucleating agent to
induce the formation of a calcium phosphate layer. The effect of immersion time on the morphology
of the precipitate was monitored with a scanning electron microscope. X dot maps revealed that
there is a relationship between distribution of Ca–P and ZTA surface. X-ray diffractometry patterns,
calcium/phosphor molar ratio and Fourier transform infrared spectroscopy showed that b-tricalcium
phosphate and calcium deficient hydroxyapatite precipitated onto substrates via biomimetic. The
thin filmX-ray diffraction pattern showed that the calciumdeficient hydroxyapatite decomposed into
b-tricalcium phosphate and CaO after 0?5 h of heat treatment at 700uC.
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