Understanding the setting and hardening process of wollastonite-based brushite cement. Part 2: Influence of the boron and aluminum concentrations in the mixing solution

The mixing solution of wollastonite-based brushite cement is a phosphoric acid containing metallic cations and borax. This work complements previous study devoted to the influence H3PO4 concentration, Ca/P liquid-to-solid (l/s) ratios on setting hardening process binder by providing new insight into role aluminum boron. Boron retards decreases heat released during process. It also contributes reduce macroporosity hardened material but yields poor compressive strength. With in solution, mechanical properties are greatly improved thanks precipitation an amorphous aluminophosphate which increases density matrix. But alone leads fast setting. A joint addition boron makes it possible get with optimized both fresh states.