Effect of AlF3, CaF2 and MgF2 on hot-pressed hydroxyapatite-nanophase alpha-alumina composites

Date

2008-10-02

Author

Evis, Zafer

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Nanophase alpha-alumina and hydroxyapatite composites (with and without 5 wt% AlF3, CaF2 or MgF2 added separately) were hot pressed at 1100 degrees C and 1200 degrees C to investigate their mechanical properties and phase stability. Hydroxyapatite slightly decomposed to tri-calciurn-phosphate when there was no F- present. With the addition of AlF3, CaF2 or MgF2 into the composite, it improved its thermal stability and mechanical properties. Substitution of OH- by F- ions in hydroxyapatite was verified by the change in hydroxyapatite's hexagonal lattice parameters and unit cell volume. A fracture toughness of 2.8 MPa root m and mu-hardness of 8.25 GPa were calculated for the composite containing CaF2 after the hot pressing at 1200 degrees C.

Subject Keywords

Ceramics, Chemical synthesis, X-ray diffraction, Mechanical properties

URI

https://hdl.handle.net/11511/40046

Journal

MATERIALS RESEARCH BULLETIN

DOI

https://doi.org/10.1016/j.materresbull.2007.10.032

Collections

Department of Engineering Sciences, Article

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Citation Formats

Z. Evis, “Effect of AlF3, CaF2 and MgF2 on hot-pressed hydroxyapatite-nanophase alpha-alumina composites,” MATERIALS RESEARCH BULLETIN, pp. 2643–2651, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40046.