An investigation of the microstructural and mechanical properties of tri-calcium phosphates doped with aluminum and fluoride ions

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Mühendislik Bilimleri Bölümü, Türkiye

Tezin Onay Tarihi: 2011

Öğrenci: AYDIN TAHMASEBİFAR

Danışman: ZAFER EVİS

Özet:

ABSTRACT AN INVESTIGATION OF THE MICROSTRUCTURAL AND MECHANICAL PROPERTIES OF TRI-CALCIUM PHOSPHATES DOPED WITH ALUMINUM AND FLUORIDE IONS Tahmasebifar, Aydin M. Sc., Department of Engineering Sciences Supervisor: Assoc. Prof. Dr. Zafer Evis August; 88 Pages The aim of this study was to investigate the microstructure and mechanical properties of pure tricalcium phosphate (TCP) and tricalcium phosphates doped with aluminum (Al3+) and fluoride (F-) ions at different compositions. TCP was synthesized via precipitation method and sintered at 1100C for 1 and 5 h. It was observed that density and relative density of the sintered materials were decreased by extending the sintering time. Increased densities were achieved upon Al3+ and/or F- doping. For structural analysis, XRD, SEM and FTIR spectroscopy examinations were performed. Second phases were observed in XRD studies upon doping. Due to Al3+ and F- substitution, hydroxyapatite (HA) phase was detected besides β-TCP, resulting in the formation of HA/β-TCP biphasic composites with different compositions. SEM results revealed that addition of doping ions resulted in smaller grains. In FTIR analysis, in addition to the characteristic bands of TCP, novel bands indicating the substitution of F- ions were observed in F- ion doped samples. In general, the micro hardness test revealed that Al3+ ions in large amounts had negative effects on the mechanical properties of the samples, while substitution of the F- ions had a positive effect on their mechanical properties.