The effect of nano-γAl2O3 additive on early hydration of calcium aluminate cement
The effect of nano-γAl2O3 additive on early hydration of calcium aluminate cement
复制标题
纳米γAl2O3添加剂对铝酸钙水泥早期水化的影响
DOI：
10.1016/j.conbuildmat.2017.10.071
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发表时间：
2018-01-15
影响因子：
7.4
通讯作者：
Hou, Xinmei
中科院分区：
文献类型：
--
作者：
Chen, Junhong;Liang, Chaojing;Hou, Xinmei
针对铝酸钙水泥（CAC）高温力学强度下降的问题，在水灰比（w/c）为0.36的条件下，将0.5 ~ 1.5%（质量分数）的纳米γ-Al 2 O3添加到CAC中。采用等温量热法研究了纳米γ-Al 2 O3添加剂对水泥水化热的影响。结果表明，纳米γ-Al 2 O3添加剂提高了水化放热速率，缩短了水化诱导期。X射线衍射（XRD）和热分析（TG-DTA）结果表明，水化产物主要为CaAl 2 O 4中心点10 H（2）O（CAH（10））和Ca 2Al 2 O 6中心点8H（2）O（C（2）AH（8）），纳米γ-Al 2 O3的加入使其含量明显增加。除此之外，没有其他新的相形成。用扫描电子显微镜（SEM）对水合物的微观结构进行了表征。纳米γ-Al_2O_3的加入使CAC的微观结构变得更加致密，从而提高了CAC硬化过程中的高温力学强度。(C)2017爱思唯尔有限公司版权所有
Aiming to solve the decrease of the mechanical strength of calcium aluminate cement (CAC) at high temperature, nano-gamma Al2O3 additive ranging from 0.5 to 1.5 mass% was added in CAC with water to cement ratio (w/c) of 0.36 respectively. The influence of nano-gamma Al2O3 additive on hydration heat was studied by isothermal calorimetry. It shows that nano-gamma Al2O3 additive increases heat release rate and shortens the induction period of hydration. X-ray diffraction (XRD) and thermal analysis (TG-DTA) demonstrate that the main hydrate products are CaAl2O4 center dot 10H(2)O (CAH(10)) and Ca2Al2O6 center dot 8H(2)O (C(2)AH(8)) and their amounts increase obviously with nano-gamma Al2O3 additive. Besides these, no other new phases are formed. The microstructure development of the hydrates was characterized by scanning electron microscopy (SEM). Due to the formation of smaller hydrate crystals together with amorphous aluminum gel, the microstructure of CAC with 1 mass% nano-gamma Al2O3 additive becomes much denser, which contributes to enhance the mechanical strength at high temperature during the CAC hardening process. (C) 2017 Elsevier Ltd. All rights reserved.