合成温度对含镁铝尖晶石的铝酸盐水泥晶粒尺寸及凝结性能的影响  

Influence of synthesis temperature on crystal size and setting properties of calcium aluminate cement with magnesium aluminate spinel

作　　者：陈平安[1] 李享成[1] 朱伯铨[1] 

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081

出　　处：《耐火材料》2016年第1期6-9,共4页Refractories

基　　金：国家自然科学基金面上项目(51374162);湖北省自然科学基金项目(2014CFA091)

摘　　要：为了研究合成温度对含镁铝尖晶石的铝酸盐水泥晶粒尺寸和凝结性能的影响,以白云石、工业氧化铝和轻烧镁砂为原料,按Al2O3、Mg O、Ca O质量比为71 9 20配料后混合均匀,并在高温炉中分别经1 100、1 200、1 300、1 400和1 500℃保温3 h煅烧并破粉碎至50μm以下,制备了含MA的铝酸盐水泥,对水泥试样进行了XRD和SEM分析,并检测了凝结时间。研究结果表明：含MA的铝酸盐水泥中的CA、MA和CA2相分别在900、1 100和1 200℃生成。当合成温度从1 100℃升高至1 500℃时,水泥中MA的晶粒尺寸从纳米到微米级可控,CA或CA2的粒径从2～3μm逐渐长大至5μm以上,并烧结在一起形成骨架,MA包裹在CA或CA2相周围。随着合成温度的升高,水泥的凝结时间延长,其原因一方面在于CA或CA2晶粒的长大,致使水化活性较低;另一方面在于MA晶粒的长大阻碍了水与内部CA或CA2的反应,对水泥的水化过程有明显的阻碍作用。Dolomite,industrial alumina and caustic magnesite were used as starting materials to study the influence of temperature on the crystal size and setting properties of aluminate cement with magnesium aluminate spinel. The starting materials were mixed homogeneously according to the mass ratio of 71 9 20 of Al2O3 Mg O Ca O,heated to 1 100,1 200,1 300,1 400,1 500 ℃,respectively,in a high temperature furnace and soaked for 3 h. After that,the cement bulk was crushed to below 50 μm. The MA bearing aluminate cement was characterized by XRD and SEM,and the setting time was tested. The results show that the phases of CA,MA and CA2 can be formed at 900,1 100 and 1 200 ℃,respectively. The crystal size of spinel could be controlled from nanometer to micrometer as the synthesis temperature rises from 1 100 to 1 500 ℃,and CA as well as CA2 grows from 2- 3 μm to 5 μm,and then sinter together forming skeleton,CA and CA2 crystals are surrounded by MA crystals. Meanwhile,the setting time delays with the synthesis temperature rising due to the growth of CA or CA2 crystals,decreasing the hydration activity; and the growth of MA crystals,hindering the reactions between water and CA or CA2,thus obviously hindering the hydration of the cement.

关 键 词：铝酸盐水泥 镁铝尖晶石(MA) 合成温度 晶粒尺寸 凝结时间 

分 类 号：TQ175[化学工程—硅酸盐工业]