Sintering studies of synthesised manganese-oxide-doped calcium phosphate via wet chemical precipitation method
Document Type
Article
Publication Date
1-1-2014
Abstract
The beneficial effects of incorporating small amounts of manganese oxide, MnO2 (0.05, 0.1, 0.3, 0.5 and 1.0 wt%) into biphasic calcium phosphate in promoting sintering and its effect on physical and mechanical properties of the dense sample sintered at 1000-1400 degrees 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 99.5% was obtained for biphasic calcium phosphate doped with 0.3 wt% MnO2 when sintered at 1400 degrees C. The results also revealed that 0.3 wt% MnO2-doped biphasic calcium phosphate gave a maximum Vickers hardness of 5.14 GPa. On the other hand, 1.0 wt% MnO2-doped biphasic calcium phosphate exhibited highest fracture toughness of 1.32 MPa m(1/2) as compared to 0.88 MPa m(1/2) for undoped biphasic calcium phosphate when sintered at 1200 degrees C.
Keywords
Biphasic calcium phosphate, Sintering additives, Manganese oxide, Sintering
Publication Title
Materials Research Innovations
Volume
18
Issue
S6
Publisher
Maney Publishing
Publisher Location
STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND