添加剂对超细α-Al_2O_3的制备及其性能影响  

Effects of multiplex catalyst on synthesis and properties of ultrafine α-Al_2O_3 at low temperature

作　　者：邓华[1] 肖劲[1] 高慧妹[1] 万烨[1] 李劼[1] 刘业翔[1] 

机构地区：[1]中南大学冶金科学与工程学院,长沙410083

出　　处：《材料与冶金学报》2007年第4期274-278,289,共6页Journal of Materials and Metallurgy

摘　　要：采用硫酸铝和碳酸铵为原料,通过沉淀法制备前驱体碱式碳酸铝铵,采用分散剂及添加剂(MC)防止粉体颗粒的团聚,着重考查了MC在干燥、煅烧过程中的作用.研究表明,MC能有效防止前驱体在干燥过程中的团聚,促进氧化铝在煅烧过程中的相变,大幅度降低了-αA l2O3的相变温度,同时还使颗粒维持在相对"动态"的煅烧状态,减轻了颗粒形成煅烧颈及其他硬团聚的趋势,从而改善了粉体颗粒的分散性能.BET及ICP分析结果表明,MC的引入还有利于产物-αA l2O3比表面积的提高,而且对煅烧产物的杂质元素含量没有影响,产物中氧化铝的质量分数高达99.97%.The precursor of ammonium aluminum carbonate hydroxide was synthesized with precipitation method by using aluminum sulfate and ammonium carbonate as raw materials. Dispersant and additive （MC） were used to prevent agglomeration of powder particles and the effects of MC on drying and sintering processes were intensively investigated. The results show that the addition of MC can effectively prevent agglomeration of precursor in drying process, as well as has great potential synergistic effect on the phase transformation of alumina and greatly reduces the phase transformation temperature of α-Al2O3, simultaneously maintains the powder particles in a comparatively dynamic-sintering-state and the trends of necking-formation or other rigid agglomerations are remarkably decreased. Therefore the dispersion of powder particles is significantly improved. BET and ICP analysis indicate that the addition of MC is favourable to increasing the specific surface area of α-Al2O3 and has no effect on the contents of impurities in sintered products and the content of Al2O3 reaches 99. 97%.

关 键 词：Α-AL2O3 添加剂 相变 团聚 

分 类 号：TB383[一般工业技术—材料科学与工程]