Fig. 1.

Specific surface area (SSA) as a function of the Ca/P molar ratio measured by XRD. (a) SSA of CDHA powders obtained after synthesis; (b) SSA of β-TCP powders after thermal conversion (1 h at 850 °C). The colour code after calcination represents the phases quantified with the XRD analysis: orange for β-TCP + β-CPP, green for β-TCP and blue for β-TCP + HA. Vertical error bars stand for the uncertainty U_k = 2 on SSA values and horizontal error bars represent the repeatability (2.77*estimated standard deviation of the Rietveld refinement).