Ceramics-Silikáty

In order to enhance the calcination and hydration characteristics of iron bearing ye′elimite (FY), synthetic C₄A_2.9F_0.1$ was prepared under different temperatures with varying amounts of phosphorus (P₂O₅), magnesium (MgO), and a combination of P₂O₅ and MgO, to investigate early hydration behaviour. The results demonstrate that the formation of FY doped with P₂O₅ at 1200 °C is significantly enhanced, with an increase in hydration observed for 0.5 mass% P₂O₅ compared to 0.25% mass P₂O₅. At 1250 °C, the FY primarily consists of FR as the major phase, along with a small amount of remaining anhydrite. However, the presence of anhydrite decreases when doped with P₂O₅, disappearing completely at 1300 °C. Without any gypsum present, the FY doped with P₂O₅ exhibits higher hydration activity than pure FY alone. On the other hand, FY doped with MgO shows a broadened main peak within 24 hours, but a lower hydration activity compared to the pure FY alone. Although gypsum accelerates uniform hydration, doping with P₂O₅ still promotes the hydration activity while doping FY with M hinders the broadening range characteristics and reduces the overall hydration activity.