材料期刊网

以工业氧化铝、轻烧氧化镁及重质碳酸钙为原料，按Al2O3、MgO、CaO质量比为711613配料，球磨混合后，分别在900、1000、1100、1300和1500℃保温3 h合成含镁铝尖晶石的铝酸盐水泥，然后分析了合成试样的物相组成、显微结构和凝结时间。结果表明：1）在900℃保温3 h后合成试样中已有CA生成，1000℃保温3 h后已有MA生成，1100℃保温3 h后已有CA2生成；1300℃保温3 h后，原料已完全反应，产物全部由CA、CA2、MA组成。2）在1300和1500℃保温3 h合成的水泥中，CA和CA2呈板状，MA呈粒状或八面体状， MA均匀分布在CA和CA2周围；在1500℃保温3 h合成的水泥中，CA、CA2、MA的晶粒比1300℃保温3 h合成的发育更完整，晶粒尺寸也更大。3）1300和1500℃保温3 h合成的水泥的初凝时间分别为37和43 min，终凝时间分别为115和163 min。

The magnesium aluminate spinel containing aluminate cement was prepared with starting mate-rials of industrial alumina,light burned magnesia and heavy weight calcium carbonate.The starting mate-rials were batched according to the Al2O3 MgO CaO mass ratio of 71 16 13,ball milled,and fired at 900,1 000,1 100,1 300 and 1 500 ℃ for 3 h,respectively.Phase compositions,microstructure and setting time of the prepared cement were investigated.The results indicate that:(1 )CA,MA and CA2 form at about 900,1 000 and 1 100 ℃,respectively;CA,CA2,and MA are detected in the specimen treated at 1 300 ℃ for 3 h,indicating a complete reaction of the starting materials;(2)SEM analysis indicates that in the cement fired at 1 300 or 1 500 ℃ for 3 h,CA and CA2 are tabular,MA is granular or octahedral,and MA well distributes around CA and CA2 particles;comparatively,CA,CA2,MA particles of the cement fired at 1 500 ℃ for 3 h develop better with larger crystal size;(3 )the initial setting times of the cement fired at 1 300 and 1 500 ℃ for 3 h are 37 min and 43 min,respectively,and the final setting times are 1 15 min and 163 min,respectively.