高镁水泥制备及其膨胀性能  

Preparation and expansion property of high magnesia cements

作　　者：邓敏[1] 朱颖灿[1] 

机构地区：[1]南京工业大学材料科学与工程学院,材料化学工程国家重点实验室,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2009年第4期1-5,共5页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家重点基础研究发展计划(973计划)资助项目(2009CB623105);国家“十一五”科技支撑计划资助项目(2006BAF02A25)

摘　　要：制备MgO质量分数分别为6%、9%、12%和15%的高镁水泥,通过扫描电镜(SEM)、扫描电镜/能谱联合仪(SEM/EDS)、X射线衍射(XRD)等检测方法和膨胀性试验分析MgO质量分数对熟料煅烧和净浆膨胀性能的影响.结果表明:随着MgO质量分数增加,熟料煅烧时液相量增加,熟料密实度提高.当熟料中MgO质量分数为12%时,养护温度由20℃增加到38℃,试件90d龄期膨胀率由0.120%增加到0.244%;38℃养护时,掺入35%粉煤灰的试件90d龄期膨胀率由0.244%降至0.070%.当MgO质量分数高于12%时,尽管存在粉煤灰的抑制作用,但高镁水泥依然能产生一定膨胀,可以有效地补偿混凝土的温降收缩.High magnesia cements, containing 6% , 9%, 12% , and 15% of MgO were prepared. By scanning electron microscopy （ SEM ） , scanning electron microscopy/energy differential spectrometer （SEM/EDS）, X-ray diffraction （XRD）, and expansion test, effects of MgO content on the clinker calcination and the expansion property of pastes were analyzed. Results showed that as the MgO content increased, the liquid phase increased during calcination, thus leading to the increase of the clinker density. When the MgO content was 12% , the expansion of 90 d-aged specimen increased from 0. 120% to 0. 244% when the curing temperature elevated from 20 ℃ to 38 ℃. If 35% fly ash was used to replace cement, the 90 d-aged expansion decreased from 0. 244% to 0. 070% at 38 ℃. When the MgO content was higher than 12% , despite the depression effect of fly ash, the high magnesia cement still produced a certain expansion, thus compensating the shrinkage caused by temperature decreasing.

关 键 词：膨胀 高镁水泥 MGO 粉煤灰 

分 类 号：TQ172[化学工程—水泥工业]