摘要
本文采用X射线衍射分析方法,研究了影响C_(11)A_7·CaF_2稳定性的因素,结果表明C_(11)A_7·CaF_2在1450℃以内,能够稳定存在;Mgo,K_2O对C_(11)A_7·CaF_2稳定性没有影响;Na_2O、P_2O_5和CaO能与C_(11)A_7·CaF_2发生反应、分别生成少量NC_6A_3、Ca_5F(PO_4)_3和C_3A,但在硅酸盐水泥熟料的正常煅烧制度下,反应程度较低,对C_(11)A_7·CaF_2稳定性不大.熟料中铝酸盐相存在的形式,主要取决于氟在熟料中的分布,CaF_2掺量较低,温度超过1350℃,C_(11)A_7CaF_2消失,生成C_3A;CaG_2掺量较高时,温度高达1450℃,熟料中的铝酸盐相仍为C_(11)A_7·CaF_2,而不生成C_2A.
The faetors affecting the stability of C11A7CaF2 have been inrestigated. It has been shown that C11A7CaF2can exist stably in the range of temperature 1450℃. Mgo and K2O do not affect the stability of C11A7CaF2; Na2o,P2O5and Cao Can react with C11A7CaF2, forming a few phases Such as Nc8A3,Ca5F(PO4)3-and C3A respectirely. In the condition of normal burning for Portland cement clinker, the reaction degree as showh above is lower withont affecting the stability of C11A7CaF2. The existing form of alluminate phase in the clinker depends on the distribution of fluorine in the clinker. When both the content of doped-CaF2is lower and the temperature exceeds over 1350℃ , C11A7CaF2 disappears forming C3A When the content of doped -CaF2 is higher and temperature is up to 1450℃ , the of aluminate phase is still C11A7CaF2. not C3A.
