Thermal conductivity of porous alumina ceramics prepared using starch as a pore-forming agent
Thermal conductivity of porous alumina ceramics prepared using starch as a pore-forming agent
复制标题
DOI：
10.1016/j.jeurceramsoc.2008.06.018
复制
发表时间：
2009-02
影响因子：
5.7
通讯作者：
Z. Živcová;E. Gregorová;W. Pabst;D. Smith;A. Michot;C. Poulier
中科院分区：
文献类型：
--
作者：
Z. Živcová;E. Gregorová;W. Pabst;D. Smith;A. Michot;C. Poulier
研究了使用不同类型的淀粉（马铃薯淀粉、小麦淀粉、玉米淀粉和大米淀粉）作为成孔剂制备的多孔氧化铝陶瓷在室温至 500°C 范围内的导热率。对不同孔隙率（6-47% 范围内）的氧化铝陶瓷测量的温度依赖性采用二阶多项式和 1/T 型关系进行拟合，并与致密氧化铝的现有文献数据进行比较。研究发现，相对热导率 kr=k/k0 的孔隙率依赖性可以通过 kr=exp(−1.5ψ/(1−ψ)) 形式的修正指数关系很好地描述，其中 ψ 是孔隙率。这一发现与其他文献数据一致，似乎表明所有具有由短效成孔剂产生的微结构的多孔材料的共同特征。
The thermal conductivity of porous alumina ceramics prepared using different types of starch (potato, wheat, corn, and rice starch) as pore-forming agents is investigated from room temperature up to 500°C. The temperature dependence measured for alumina ceramics of different porosity (in the range 6–47%) is fitted with second-order polynomials and 1/T-type relations, and compared to available literature data for dense alumina. It is found that the porosity dependence of the relative thermal conductivity kr=k/k0is well described by a modified exponential relation of the form kr=exp(−1.5ϕ/(1−ϕ)), where ϕ is the porosity. This finding is in agreement with other literature data and seems to indicate a common feature of all porous materials with microstructures resulting from fugitive pore-forming agents.