粉煤灰和矿粉对磷酸镁水泥性能的影响  

Influence of Fly Ash and Slag on the Properties of Magnesium Phosphate Cement

作　　者：李国新[1] 仝万亮 张歌[1] 吴燕[1] 史玲[1] 黄汝杰[1] 

机构地区：[1]西安建筑科技大学,西安710055

出　　处：《硅酸盐通报》2016年第2期352-357,共6页Bulletin of the Chinese Ceramic Society

基　　金：陕西省教育厅专项科研计划项目(2013JK0975)

摘　　要：磷酸镁水泥(magnesium phosphate cement,MPC)是一种新型气硬性胶凝材料,在其中掺入矿物掺合料可改善其性能。本文采用高纯度死烧Mg O、磷酸二氢铵及硼砂配制了磷酸镁水泥,掺入一定量粉煤灰或矿粉,研究了这两种矿物掺合料对磷酸镁水泥凝结时间、力学性能及耐水性能的影响。结果表明:随着粉煤灰和矿粉掺量的增加,MPC凝结时间缩短;砂浆试件抗压强度呈先升高后降低趋势,当掺量为10%时,抗压强度最高,同等掺量的矿粉对MPC早期和后期强度的贡献均优于粉煤灰的贡献;粉煤灰的掺入提高了MPC的耐水性,而矿粉的掺入却有降低MPC的耐水性的趋势;XRD测试表明,不掺掺合料、掺粉煤灰、掺矿粉的MPC的主要反应产物均为Mg NH4PO4·6H2O和一些非晶相,掺矿粉的MPC试件浸水28 d后,表面浸出物主要为Mg NH4PO4·6H2O。Magnesium phosphate cement （MPC） is a new type of gas hardening cementitious material, adding mineral admixture can improve its performance. In this paper, MPC was prepared with high purity dead burned magnesium oxide, ammonium di-hydrogen phosphate, borax, and a certain amount of fly ash or slag, The influences of fly ash and slag on the setting time, mechanical property and water resistance of MPC were studied. The results demonstrate that with the increase of fly ash and slag content, the setting time of MPC pastes shortened, the compressive strength of mortars presented the trend of increasing firstly and then decreasing. When the content is up to 10%, the compressive strength is the highest. The same content of slag contributed to the early and late strength of MPC was better than fly ash. Fly ash improved the water resistance of MPC, but the slag decreased the water resistance of MPC. The results of XRD demonstrate that the main product of MPC paste with no mineral admixture or with fly ash and slag is MgNH4PO4· 6H2O and some amorphous phase, the sample of MPC with slag immersed in water for 28 d, the main ingredients of the surface leaching substances is MgNH4PO4· 6H2O.

关 键 词：磷酸镁水泥 粉煤灰 矿粉 凝结时间 性能 

分 类 号：TU525[建筑科学—建筑技术科学]