低碱度钢渣水热反应特性及其机理的研究

Hydrothermal Performance and Its Mechanism of Low Alkalinity Steel Slag in Autoclaved Condition

通过力学性能、化学结合水量的测定，研究了2种低碱度钢渣的水热反应特性；应用扫描电镜、X射线衍射、红外光谱等，研究了低碱度钢渣蒸压试件的水化产物形貌和晶体结构．结果显示，在1．2MPa饱和蒸汽压下，2种低碱度钢渣的蒸压性能差异较大，掺入少量石灰（质量分数为5％）可以较大幅度地提高低碱度钢渣蒸压试件的强度；参与反应的物相为镁蔷薇辉石和玻璃相；形成的主要水化产物α—C2SH的形貌并不是连生差的片状晶体，而是晶粒尺寸为0．5～1．0μm的不规则颗粒，这一形貌特征有利于蒸压硅酸盐制品水化产物的设计及其性能的改善．

Autoclaved performances of two low alkalinity steel slags were studied with mechanical properties and bound water. And their microscopic morphologies and crystal structures were investigated with scan electronic microscope （SEM）, X-ray diffraction （XRD）, infrared spectrum （IR）. The results show that in 1.2 MPa, autoclaved performances of the two low alkalinity steel slags are different. The compressive strengths of low alkalinity steel slags autoclaved samples can be increased by adding lime （5%）. Reactive minerals are merwinite and glass phase, and the hydration product formed is α-C2 SH with crystal grain size of 0.5- 1.0μm instead of crystal plate. The appearance of α-C2 SH is favorable for design of calcium silicate hydrate of autoclaved silicate samples and improving its performances.