Sintering and mechanical properties of biomaterials based on the tricalcium phosphate and magnesium fluoride

The sintering and the mechanical properties of tricalcium phosphate–magnesium fluoride composites have been investigated. The rupture strengths of the samples were studied using the Brazilian test. This property increased with both the sintering temperature and magnesium fluoride addition. The maximum mechanical strength of the composites, 9 MPa, was reached at 1300 °C. The highest performance was obtained for the tricalcium phosphate containing 7.5 wt% MgF2. This amelioration of performance is due to the presence of a liquid phase between the tricalcium phosphate and magnesium fluoride and the formation of a new compound. In fact, the value of the rupture strength is close to that of enamel (8–12 MPa). X-ray diffraction analysis of the composites revealed the presence of magnesium phosphate and fluorapatite. The IR spectra showed that most bands are associated with the phosphate group of tricalcium phosphate. The microstructure of the composites shows a new needle form, which is probably related to the new phases.