Papers by Keyword: Manganese Doping

Abstract: Dense pure biphasic calcium phosphate (BCP) and Mn-doped BCP ceramics were fabricated via uniaxial pressing using the sol-gel derived powders. The compacted discs were sintered in air atmosphere with temperatures ranging from 1000 °C to 1400 °C. All powders have been proved to show HA and β-TCP phases only. Manganese doping improves the densification in the BCP structure as the relative density increased with Mn doping and also sintering temperature. Considerable grain growth has been observed at 1300 °C for Mn-doped BCP samples compared to the pure BCP. 15 mol% Mn showed the maximum hardness value of 6.66 GPa at 1400 °C compared to pure BCP of only 2.89 GPa. Similarly, the Mn-doped BCP has superior fracture toughness where it attained maximum values of 1.05 MPam1/2 at 1400 °C compared to 0.72 MPam1/2 at 1300 °C of pure BCP. In a nutshell, Mn doping has successfully brought improvement in the mechanical properties of the BCP.

Abstract: Manganese is one of metallic elements which appear in biological apatite like bone and teeth. Its important effect on the growth and development of bone has been well known. Here, we have synthesized manganese-doped hydroxyapatite (HA) via sol-gel method. White ammoniacal solution of monomers were refluxed until white gel formed, followed by drying and calcination at 500 – 900°C. Four different concentration of manganese (2, 5, 10 and 15 mol%) were successfully incorporated into HA crystals. XRD analysis showed that the crystallinity increased with the increased amount of manganese. SEM measurement also showed that individual particles become bigger with the increasing content of Mn. Tricalcium phosphate appeared as an additional phase when calcined at 800°C. It was also proven that the incorporation of manganese reduced the peak intensity of tricalcium phosphate. FTIR analysis is in good agreement with the results from XRD measurement where the peaks of OH (630 cm-1) and PO4 3- (565 cm-1, 601 cm-1, 960 cm-1, 1020 cm-1 and 1100 cm-1) bands of HA phase show higher intensity with the increasing concentration of manganese. FTIR measurement also showed that the presence of HPO4 2- (880cm-1) decreased in intensity with the increased Mn content, showing that the anion exist in less crystalline phase of HA.