硅酸盐学报

用环境扫描电镜原位定量追踪K-PSDS型地聚合物混凝土界面区的水化过程

作者：张云升孙伟林玮郑克仁沙建芳刘斯凤

单位：东南大学材料科学与工程系东南大学材料科学与工程系东南大学材料科学与工程系东南大学材料科学与工程系东南大学材料科学与工程系东南大学材料科学与工程系南京 210096 南京 210096 南京 210096 南京 210096 南京 210096 南京 210096

关键词：地聚合物水泥界面区水化过程原位定量追踪偏高岭土

分类号：TU528.01

出版年,卷(期):页码：2003,31(8):806-810

DOI：

摘要：

应用环境扫描电镜(ESEM)原位定量追踪K-PSDS型(KOH激发合成的PSDS型)地聚合物水泥混凝土在相对湿度80％条件下界面区水化产物生成、发展和演化的过程。实验结果表明:界面区和基体区的ESEM形貌在水化早期差别较大,界面区存在许多大的空洞(50μm),而基体区颗粒分布均匀、密实;随龄期的增长,凝胶状产物在界面区空洞周缘淀积,并向外伸展,空洞逐渐被填满、湮没;到后期二者形貌基本没有太大区别,但通过能量散射分析(EDXA)发现界面区n(K)/n(Al)和n(Si)/n(Al)高于基体区,表明K和Si在界面区富集,从而造成胶凝产物化学组成的差异。另外,界面区在任何龄期均未出现尺寸规则的结晶产物,而仅生成了海绵状胶凝体。

A technique of environment scanning electron microscope (ESEM) was used to quantitatively observe in situ and record the hydration process of interfacial transition zone(ITZ) and K - PSDS geopolymer matrix under R. H. 80% . The ESEM micrographs and corresponding EDXA show that microstructure of ITZ is quite different from that of matrix at the early stage. There exist many large voids (50 fj.m) in ITZ, while it is just the reverse for the matrix. With the proceeding of hydration gel products are gradually precipitated on the edges of these voids and then extended outward, and as a result these voids are fully filled. At the later stage, no obvious differences between ITZ and matrix can be seen from the micrographs. But studies on these two regions by EDXA display that the contents of n(K)/n(Al) and n(Si)/n(Al) in ITZ are higher than that in matrix. This indicates that the accumulation of K and Si in ITZ results in the chemical composition difference between ITZ and matrix. In addition, well-developed crystals are not found in ITZ and matrix at any ages, while sponge-like gel is always observed.

基金项目：

国家自然科学基金(50278018);;国家自然科学重点基金(59938170)

作者简介：

参考文献：

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