沉淀法制备超细α-Al_2O_3  

PREPARE ULTRAFINE α-Al_2O_3 POWDER BY PRECIPITATION METHOD

作　　者：肖劲[1] 万烨[1] 周峰[1] 李劼[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《中国陶瓷工业》2007年第3期14-16,9,共4页China Ceramic Industry

摘　　要：以Al2(SO4)3与(NH4)2CO3为原料,采用液相沉淀法,制备出前驱物碳酸铝铵(AACH),并烧结得到超细Al2O3粉末。通过分析AACH的热重曲线,确定了AACH的高温分解过程;并结合对AACH在不同烧结温度下所得产物XRD图谱的分析,确定了AACH的高温相变过程为:AACH→AlOOH→Al2O(3无定型)→γ-Al2O3→θ-Al2O3→α-Al2O3。运用扫描电镜(SEM)对样品的形貌、分散情况进行表征,并估量出α-Al2O3颗粒的粒径大小;测定了α-Al2O3粉末的比表面积,并计算出α-Al2O3颗粒的粒径大小。结果表明,采用该方法能获得平均粒径约为50nm,形貌为球形且分散性良好的α-Al2O3粉体。Ammonium aluminum carbonate hydroxide （AACH） was synthesized as the precursor by the precipitation reaction of aluminum sulfate and ammonium carbonate. Then AACH was agglomerated to get ultrafine Al2O3 powder. The thermal decomposition reaction of AACH was confirmed by analyzing the DTNTGA curves. The DTNTGA curves and XRD show that the phase transformation of AACH in sintering process was： AACH→AIOOH→amorphous Al2O3→γ-Al2O3→θ-Al2O3→α-Al2O3. The morphologies and dispersion of the samples were characterized by SEM and the particle size of α-Al2O3 was measured. The specific area of α-Al2O3 was tested and the particle size of α-Al2O3 was calculated. The results show that the average size of α-Al2O3 powder is about 50nm and they are in spherical shape and well dispersed.

关 键 词：超细α-Al2O3 碳酸铝铵 相变 分散 

分 类 号：TQ133.1[化学工程—无机化工]