【摘要】 以白云石、菱镁矿、硅石和锆英石为原料,采用二步煅烧和消化工艺制备出了CaO含量为35%,C/S比（CaO/SiO₂分子比）为2.5,ZrO₂含量分别为2%、4%、6%、8%的稳定性锆镁白云石合成材料.研究了烧成过程中材料的物相变化,测定了1 500℃、1 550℃、1 600℃、1 650℃烧后材料的体积密度、显气孔率,线收缩率和抗水化性,并采用SEM分析了材料的显微结构.结果表明:1 000℃时,锆英石分解生成CaZrO₃,1 100℃后硅酸钙开始生成,1 300℃后CaO完全反应;随烧成温度提高,材料的致密度提高,1 600℃烧后材料的体积密度增加到3.11³.16g/cm3;1 650℃烧后材料的水化增重为0.03%⁰.07%,f-CaO转变为稳定的硅酸钙和CaZrO₃等物相,材料的抗水化性显著改善.更多还原

【Abstract】 Stabilized magnesium dolomite zirconium refractory materials were prepared from natural dolomite,magnesite,silica and zirconia by two-stage calcination. The specimens were in the CaO content of 35% and C /S molar ratio of 2. 5,ZrO₂ was set in the amount of 2%,4%,6%,8%. Phase compositions after fired at different temperature were analysized and the resulting bulk densities,apparent porosities,liner shrinkages as well as hydration resistance of the sintered materials were investigated. Microstructures were observed by SEM accompanied with EDS. The results show that: zircon decomposes after 1 000 ℃ and forms calcium zirconate,calcium silicate appears after fired at 1100℃ and CaO disappears from 1300℃; compactness increases with the increasing of the firing temperature,and bulk densities reach 3. 11 3. 16 g / cm3; weight gained after sintered at 1650℃ is in the range of 0. 03% 0. 07%. The transformation of f-CaO into stabilized forms,such as calcium silicate and calcium zirconate promotes the hydration resistance of the materials significantly.更多还原