Modified Pechini synthesis of tricalcium aluminate powder

Tricalcium aluminate (Ca3Al2O6–C3A) was obtained by a modified Pechini synthesis in order to eliminate successive thermal treatments and intermediate grinding usually performed between the two sintering steps and in order to reduce the sintering temperature. Our results indicated that pure C3A was obtained, by a single step thermal treatment at 1300 °C for 4 h and 1350 °C for 1 h. The synthesis was confirmed by XRD, FT-IR and free lime analyses. The morphology of synthesised C3A was assessed by electron microscopy (SEM and TEM, HRTEM) and it was observed a high tendency of the particles to form aggregates and the individual particles seem to be single crystals. The bioactivity was assessed by specimen soaking in simulated body fluid (SBF) for 7 days; the hydrate (i.e. 3CaO∙Al2O3∙ 6H2O formed at the C3A surface), can act as nucleation centers for the resulted phosphate phases.