Publication: Sintering studies of synthesised manganeseoxide- doped calcium phosphate via wet chemical precipitation method
Date
2014
Authors
Norakmal A.
Ramesh S.
Tan C.Y.
Muchtar A.
K. Yap B.
Tolouei R.
Journal Title
Journal ISSN
Volume Title
Publisher
Maney Publishing
Abstract
The beneficial effects of incorporating small amounts of manganese oxide, MnO2 (005, 01, 03, 05 and 10 wt%) into biphasic calcium phosphate in promoting sintering and its effect on physical and mechanical properties of the dense sample sintered at 1000-1400°C were investigated. In this work, a wet precipitation method was employed to prepare biphasic calcium phosphate powder. The starting materials of calcium hydroxide and orthophosphoric acid were used in the titration process and the as-synthesised powder was subsequently doped with manganese oxide by wet milling. The X-ray diffraction analysis revealed that the phase present in the as-synthesised powder was predominantly hydroxyapatite. However, upon sintering, all the samples revealed the existence of biphasic calcium phosphate i.e. a mix phase comprising of hydroxyapatite and tricalcium phosphate. The highest relative density of 995% was obtained for biphasic calcium phosphate doped with 03 wt% MnO2 when sintered at 1400°C. The results also revealed that 03 wt% MnO2-doped biphasic calcium phosphate gave a maximum Vickers hardness of 514 GPa. On the other hand, 10 wt% MnO2-doped biphasic calcium phosphate exhibited highest fracture toughness of 132 MPa m1/2 as compared to 088 MPa m1/2 for undoped biphasic calcium phosphate when sintered at 1200°C. © W. S. Maney &Son Ltd 2014.