Influence of magnesium doping on the phase transformation temperature of β-TCP ceramics examined by Rietveld refinement

The influence of Mg doping in Ca-3(PO4)(2) on the transformation temperature of beta-tricalcium phosphate (beta-TCP) to alpha-tricalcium phosphate (alpha-TCP) was examined. A maximum substitution by 14mol% of Mg2+ on Ca2+ sites in the beta-TCP structure was determined for powders calcinated at 1025 +/- 10degreesC. X-ray powder diffraction analysis (XRPD) in combination with Rietveld method (TOPAS 2.1) was employed for quantitative phase analysis and structural refinement. The synthesized and characterized Mg-doped samples were sintered in air atmosphere in a vertical tube furnace at suitable temperatures ranging from 1460 to 1680degreesC and subsequently quenched to room temperature, in order to stabilize alpha-TCP. The beta to alpha transformation temperatures were determined by differential temperature analysis and XRPD analysis. (C) 2004 Elsevier Ltd. All rights reserved.