电场作用对水泥硬化体组成与微观结构的影响  

Influences of Electric Field on Composistion and Micro-structure of Cement Paste

作　　者：祝频[1] 王新祥[2,3] 韦江雄[2] 杨墨[2] 余其俊[2] 李建新[2,3] 郑靓[2,3] 

机构地区：[1]广东建设职业技术学院,广州510450 [2]华南理工大学材料科学与工程学院,广州510640 [3]广东省建筑科学研究院,广州510530

出　　处：《混凝土与水泥制品》2011年第7期4-9,共6页China Concrete and Cement Products

基　　金：国家自然科学基金(50602016;50972045)

摘　　要：利用XRD、DSC/TG、SEM/EDS和显微硬度等测试手段对电场作用后砂浆内部预埋水泥净浆的组成和微观结构进行了分析。结果表明:电场作用的初期,阴极附近生成大量结晶较好的Ca(OH)2,且取向性指数大;然而随着通电时间的延长,Ca(OH)2的生成趋于稳定,且取向性指数逐渐减小;阴极附近试样的显微硬度呈现先减小后增大的发展规律;扫描电镜的结果揭示,通电初期阴极附近的净浆表面富集大量Ca(OH)2,随着电场作用时间延长,阴极附近生成富钠硅酸盐相。由此可见,电场作用在一定程度上弱化了阴极附近的砂浆与混凝土。The composition and micro-structure of cement paste in electric field are investigated by instruments of XRD,DSC/TG,SEM/EDS and microhardness.The results show that in the initial stage,there is a large quantity of better crystallographic Ca（OH）2 with very high orientation near the cathode.However,the information of Ca（OH）2 becomes stable and the orientation of Ca（OH）2 gradually decreases with the extension of conduction time.The microhardness of the embedded pastes decreases at the beginning of electric field,and then increases at the end of electric field.The results of SEM indicate that a lot of Ca（OH）2 gather on the surface of cement paste near by the cathode,but there are many silicates doping sodium in the neighborhood of the cathode after long electrification.A a result,the bond between mortars and concrete near the cathode is decreased in some extent by electric field.

关 键 词：电场作用 水泥硬化体 微观结构 显微硬度 

分 类 号：TU528[建筑科学—建筑技术科学]