工业氧化铝粒度分布对合成CA6多孔材料的性能、相组成和显微结构的影响  

Influence of particle size distribution of γ-Al_2O_3 on properties,phase composition and microstructure of porous calcium hexaluminate

作　　者：李天清[1,2] 李楠[1] 王锋刚 贺中央 

机构地区：[1]武汉科技大学湖北省耐火材料与高温陶瓷重点实验室,武汉430081 [2]濮阳濮耐高温材料(集团)股份有限公司

出　　处：《耐火材料》2008年第5期334-336,共3页Refractories

摘　　要：以不同粒度分布(d50分别为3.02、3.64、14.64、18.62μm)的工业氧化铝粉和轻质碳酸钙微粉(d50=5.14μm)为原料,按CA6中Al2O3与CaO的化学计量比配料,在50 MPa下成型为25 mm×25 mm圆柱试样,经110℃干燥24 h后,在空气气氛中于1 500℃煅烧3 h合成六铝酸钙多孔材料,并借助XRD和SEM等研究了工业氧化铝粒度分布对该多孔材料的性能、相组成和显微结构的影响。研究表明:随着工业氧化铝粒度的增大,试样的显气孔率逐渐增加,气孔孔径增大,耐压强度则大幅度下降;CA6的生成量随着工业氧化铝粒度的减小而显著增加,当d50减小到4μm时,基本上全部生成CA6;制备d50<5μm的高气孔率、高强度的CA6多孔材料,需将工业氧化铝的d50控制在4μm左右。The porous calcium hexaluminate specimens were prepared using γ-Al2O3 with different particle size distri- butions （ d50 =3.02,3.64,14.64, and 18.62 μm） and lightweight calcium carbonate powders （ d50 =5.14 μm） as starting materials, batching according to the stoichiometric proportion of Al2O3 and CaO in CA6, shaping into column of Φ25 mm ×25 mm under 50 MPa, after drying at 110 ℃ for 24 h,calcining at 1 500 ℃ for 3 h. Influences of particle size distributions of γ-Al2O3 on properties, phase composition and microstructure of porous calcium hexaluminate were studied by means of XRD and SEM The results indicated that the apparent porosity and the air-hole aperture of the specimens increased but the crushing strength decreased markedly with particle size of γ-Al2O3 increasing. The forming amount of CA6 increased remarkably with the particle size of γ-Al2O3 decreasing. When d50 of γ-Al2O3 reduced to about 4 μm, the calcium hexaluminate content was nearly 100%. The d50 of γ-Al2O3 should be controlled at about 4 μm to prepare CA6 porous materials （d50 〈5 μm） with high apparent porosity and high crushing strength.

关 键 词：六铝酸钙 多孔材料 粒度分布 工业氧化铝 

分 类 号：TQ536.4[化学工程—煤化学工程] TF125.6[冶金工程—粉末冶金]