CaO-Al_2O_3-P_2O_5三元系统富铝区水硬活性的研究

STUDY ON HYDRAULIC ACTIVITY OF ALUMINUM-RICH AREA IN CaO-Al_2O_3-P_2O_5 SYSTEM

首次研究了ＣａＯ－Ａｌ２Ｏ３－Ｐ２Ｏ５三元相图中Ｃ１２Ａ７－Ｐ２Ｏ５连线附近富铝区域组成的水硬活性．讨论了高场强阳离子Ｐ５＋极化作用形成［ＰＯ４］３－四面体对体系相组成，进而对其水硬活性的影响．由所研制的磷铝酸盐水泥中，得到了新化合物———三元磷铝酸钙．通过ＸＲＤ，ＩＲ和电子探针微区分析（ＥＰＭＡ）等手段，证实了α－Ｃ３Ｐ和ＣＡ矿相在结构上的变化．由于三元磷铝酸钙化合物与改性α－Ｃ３Ｐ（３ＣａＯ·Ｐ２Ｏ５）和ＣＡ（ＣａＯ·Ａｌ２Ｏ３）以及适量的玻璃相的共同作用，在该区域可以得到早强。

For the first time , the hydraulic activity of the composition near the connecting line of C_12A_7-P_2O_5 in the aluminum-rich area of CaO-Al_2O_3-P_2O_5 ternary phase diagram was studied. Influences of the tetrahedron^3+ formation caused by polarization of high field intensity cation P^5+ on the phase composition of ternary system and on its hydraulic activatiy are discussed . A new prospective phase L — a ternary phosphoaluminate compound has been formed in phosphoaluminate cement here. The techniques of XRD, IR, EPMA, etc. were conducted to verify the modification in structure and composition of CA(CaO·Al_2O_3) and α-C3P (α-3CaO·P_2O_5). The results obtained here indicate that by the occasion of new phase L with modified phases α-C_3P and CA and adequate amount of glass, a new cementitious material would be developed which has the characters of early and high strength, and steadily growing long-term strength. Finally, the hydraulic mechanism of cement is also studied.