氟硫掺杂对MgO固溶及高镁熟料结构与性能的影响

Effect of Dopping Fluorine and Sulphur on the Solid Solubility of MgO and the Microstructure and Properties of High MgO Clinker

利用化学分析、力学性能测试、岩相分析和XRD Rieitveld精修,研究了氟硫掺杂对高镁熟料中MgO固溶量、熟料强度、熟料显微结构和萃取阿利特的指纹区XRD特征峰及晶胞。结果显示:掺加一定量的SO3、CaF2能有效促进熟料中MgO的固溶。当掺加的CaF2掺量≤0.25%时,MgO固溶量随SO3含量增加而增加。随着熟料中CaF2掺量的增加,SO3含量的变化对MgO的固溶影响越来越弱。在SO3掺量≤1.2%,CaF2掺量的增加更利于熟料中MgO的固溶。单掺SO3时,熟料28 d强度随着SO3掺量增大而降低。而在同时掺有0.50%CaF2的熟料中,随着SO3掺量的增大,熟料的3 d、28 d强度均呈先增加后减少的趋势。在掺杂适量的CaF2的前提下,掺加一定量的SO3有助于提高熟料的强度,但存在一个最佳掺量。且在一定范围内熟料中CaF2的含量越高,水泥熟料的后期强度也越高。在熟料中同时含有SO3和MgO时,室温下能稳定M2-M3型的的阿利特。且在掺杂一定量的SO3时,随着熟料中CaF2含量的提高,阿利特的对称性也会逐步提高。与仅掺加MgO的样品相比,SO3、CaF2的掺杂使得alite的a轴稍有变小、b轴和c轴稍有变大,晶轴角则基本不变。

By using chemical analysis,mechanical property testing,petrographic analysisand XRD Rietveld method,the effects ofdoping sulfur and fluorin on the solid solubility of MgO,the strength,microstructure of clinker samples were investigated,and thecharacteristic peak and the cellparameters of the extracted alites were analysesed with XRD retveld refining. The resultsshowed： adding a certain amount of SO3,CaF2 in the clinker,the MgO solid solubility could be effectively promoted. When theadditioncontent of CaF2≤ 0.25%,the solid solubility of MgO increases with the increase of SO3 content. With the increase of CaF2 content,the effect of the SO3 content change on the solid solubility of MgO was more and more weak. When the content of SO3≤ 1. 2%,increase of CaF2 contentwas moreconducive tothe solid solubility of MgO. Only adding SO3,the compressive streng that 28 d age with the content of SO3 increases was decreases. Adding 0. 50% CaF2 simultaneously,the strengths at 3 d and 28 d ages were increase atfirst and then decreased with the increase of SO3 content. On the proper content of CaF2,adding a certain amount of SO3 was helpful to improve the strength of the clinker,and there exists an optimaldosage. And within a proper addition range of CaF2,the concentration of CaF2 was more; the strength of clinker was higher. Solid solution of both SO3 and MgO,the M2-M3 polymorph of alite could be stabilited room temperature. And in the condition of adding aproper amount of SO3,the symmetryof alite will improved with the content of CaF2 increase. Compared with only adding MgO samples,SO3 and CaF2simultaneous doping made the a axis of alitecell slightly smaller,the b and C axisslightlylarger,and crystal axial angles almost unchanged.