title: Mechanical properties of bovine hydroxyapatite (BHA) composites doped with SiO2, MgO, Al2O3, and ZrO2.
abstract: Biologically derived hydroxyapatite from calcinated (at 850 degrees C) bovine bones (BHA) was doped with 5 wt% and 10 wt% of SiO(2), MgO, Al(2)O(3) and ZrO(2) (stabilized with 8% Y(2)O(3)). The aim was to improve the sintering ability and the mechanical properties (compression strength and hardness) of the resultant BHA-composites. Cylindrical samples were sintered at several temperatures between 1,000 and 1,300 degrees C for 4 h in air. The experimental results showed that sintering generally occurs at 1,200 degrees C. The BHA-MgO composites showed the best sintering performance. In the BHA-SiO(2) composites, extended formation of glassy phase occurred at 1,300 degrees C, resulting in structural degradation of the resultant samples. No sound reinforcement was achieved in the case of doping with Al(2)O(3) and zirconia probably due to the big gap between the optimum sintering temperatures of BHA and these two oxides.
authors.affiliation: School of Engineering, Industrial Engineering Department, Marmara University, Goztepe Campus, Ziverbey, Kadikoy, Istanbul 34722, Turkey. foktar@eng.marmara.edu.tr
authors.forename: Faik Nüzhet
authors.initials: FN
authors.lastname: Oktar
authors.forename: Simeon
authors.initials: S
authors.lastname: Agathopoulos
authors.forename: L Sevgi
authors.initials: LS
authors.lastname: Ozyegin
authors.forename: Oguzhan
authors.initials: O
authors.lastname: Gunduz
authors.forename: Nermin
authors.initials: N
authors.lastname: Demirkol
authors.forename: Yahya
authors.initials: Y
authors.lastname: Bozkurt
authors.forename: Serdar
authors.initials: S
authors.lastname: Salman
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D000818:Animals; D001696:Biomechanical Phenomena; D018786:Bone Substitutes / Q000737:chemistry; D002417:Cattle; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D019245:Compressive Strength; D006882:Hydroxyapatites / Q000737:chemistry*; D008277:Magnesium Oxide / Q000737:chemistry*; D008422:Materials Testing; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D015040:Zirconium / Q000737:chemistry*
chemical_list: D018786:Bone Substitutes; D020099:Coated Materials, Biocompatible; D006882:Hydroxyapatites; D008277:Magnesium Oxide; D012822:Silicon Dioxide; D015040:Zirconium; D000537:Aluminum Oxide; C028541:zirconium oxide