材料期刊网

针对以往合成 CA6－MA 轻质骨料主要采用固体起始物料时 CaO 和 MgO 分散度有限之不足，以菱镁矿、碳酸钙和氢氧化铝为主要原料，尝试了用可溶性盐 CaCl2（加入质量分数分别为1％、3％、5％、7．2％）和MgCl2·6H2 O（加入质量分数分别为1％、3％、5％、7％、9％）分别替代碳酸钙和菱镁矿，研究了其对 CA6－MA 轻质料的体积密度、强度和显微结构的影响。结果表明：1）CaCl2和 MgCl2·6H2 O 分别替代碳酸钙和菱镁矿作为CaO 和 MgO 源均可制得 CA6－MA 轻质骨料。2）MgCl2·6H2 O 或 CaCl2的加入对 CA6－MA 轻质骨料的物相影响不大，却明显改变了轻质骨料的显微结构；与引入 CaCl2相比，引入 MgCl2·6H2 O 更有利于生成交叉排列的片状 CA6及制备低体积密度、高强度、微孔的 CA6－MA 轻质微孔骨料。3）MgCl2·6H2 O 的最佳加入量为5％（w）。

Aiming at solving the limited dispersion of CaO and MgO in the previously prepared CA6 -MA lightweight aggregates,CA6-MA lightweight aggregates were prepared using magnesite,calcium carbon-ate and aluminum hydroxide as starting materials and soluble salts MgCl2 ·6H2 O(1%,3%,5%,7%,9%, by mass)and CaCl2 (1%,3%,5%,7.2%,by mass)to replace magnesite and calcium carbonate,respec-tively.The bulk density,strength and microstructure of the lightweight aggregates were investigated.The results show that:(1)using soluble salts CaCl2 and MgCl2 ·6H2 O to replace calcium carbonate and mag-nesite,respectively can prepare CA6 -MA lightweight aggregates;(2)introducing CaCl2 or MgCl2 ·6H2 O has a little influence on phase composition,but obviously changes the microstructure of CA6 -MA light-weight aggregates;compared with the introduction of CaCl2 ,the introduction of MgCl2 ·6H2 O is more ad-vantageous to the preparation of CA6-MA lightweight aggregate with flake CA6 arranged across,low bulk density,high strength and micro pores;(3)the optimum addition of soluble salt MgCl2 ·6H2 O is 5%.