含SiO_2添加剂促进CaZrO_3分解机理研究  

Decomposition mechanism of CaZrO_3 promoted by SiO_2 containing additives

作　　者：尹国祥[1] 杨红[1] 孙加林[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《耐火材料》2006年第6期426-429,共4页Refractories

摘　　要：骨料部分采用60%的锆酸钙颗粒(粒度≤0.374mm和≤0.147mm),基质部分采用30%的α-Al2O3微粉和10%的含SiO2添加剂(分别为硅灰石、熔融石英、锆英石及其复合物),成型、干燥后于1550℃3h烧成,然后对烧后试样进行了扫描电镜、XRD分析,并借助相图对CaZrO3的分解机理从热力学与动力学上进行了研究。研究结果表明:含SiO2添加剂都能促进CaZrO3的分解,其扩散传质速度直接决定着CaZrO3的分解程度,硅灰石(CaSiO3)及其复合添加剂由于在与CaZrO3的反应中生成较大量的液相而使其传质速度加快,从而使CaZrO3分解的程度变大,其中以CaSiO3-SiO2复合添加剂的促进CaZrO3分解程度最大。The specimens were prepared with 60% CaZrO3 as aggregate,30% α-Al2O3 and 10% SiO2 containing additives （wollastonite, fused quartz, zircon and their composite respectively） as matrix. Decomposition mechanism of CaZrO3 was studied according to thermodynamics and dynamics by SEM,XRD and phase diagram. The results show that：the SiO2 containing additives can promote the decomposition of CaZrO3, The decomposition degree of CaZrO3 directly depends on the mass diffusion speed of the additives, Wollastonite and its composite can promote the decomposition of CaZrO3 ,and the reason is that the forming of a great amount of liquid in the reaction with calcium zirconate quickens the mass diffusion speed, The effect of wollastonite -SiO2 composite is most obvious.

关 键 词：含SiO2添加剂 锆酸钙分解 液相扩散 硅灰石 

分 类 号：TQ175.1[化学工程—硅酸盐工业]