Hydroxyapatite and zirconia composites: Effect of MgO and MgF2 on the stability of phases and sinterability

Date

2008-07-15

Author

Evis, Zafer
KUTBAY, IŞIL

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Composites of hydroxyapatite with cubic zirconia with MgO or MgF2 were pressureless sintered at temperatures from 1000 to 1300 degrees C. The reactions and transformations of phases were monitored with X-ray diffraction. For the hydroxyapatite and zirconia composites with MgO, calcium diffused from hydroxyapatite into the zirconia, and hydroxyapatite decomposed to tri-calcium phosphate at sintering temperatures higher than 1000 degrees C. Above about 1200 degrees C, CaZrO3 was formed. Composites containing the MgF2 decomposed slower than the composites with MgO which was verified by the changes in the lattice volume of the hydroxyapatite left in the composites. Fluorine ions in MgF2 diffused into hydroxyapatite which resulted in thermal stability at high sintering temperatures. Composites with MgF2 had higher hardness than those with MgO. The lowest porosity was found in a composite initially containing 10 wt% cubic zirconia and 5 wt% MgF2.

Subject Keywords

Biomaterials, Sintering, X-ray scattering, Phase transitions

URI

https://hdl.handle.net/11511/46320

Journal

MATERIALS CHEMISTRY AND PHYSICS

DOI

https://doi.org/10.1016/j.matchemphys.2008.01.009

Collections

Department of Engineering Sciences, Article

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Citation Formats

Z. Evis and I. KUTBAY, “Hydroxyapatite and zirconia composites: Effect of MgO and MgF2 on the stability of phases and sinterability,” MATERIALS CHEMISTRY AND PHYSICS, pp. 68–75, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46320.