Preparation of Light-Weight Alumina-Spinel Refractory by Foaming Process

Abstract:

In order to reduce energy costs, light-weight alumina-spinel refractories with tri-modal pores were prepared by foaming process. The influence of foaming agent and magnesia on the properties of light-weight alumina-spinel refractory was investigated. The rheology of the original slurry and the density, mechanical properties and microstructure of samples were evaluated. The results showed that light-weight alumina-spinel refractory contained a highly interconnected network of spherical cells, consisting of the large-sized cells (larger than 40 um), moderate-sized pores( averaging about 20 um) and small-sized voids, which mainly attributed to the foaming agent and in-situ formation of spinel. The cold compressive strength of the samples varied within the range of 2-12MPa, corresponding to densities of 0.8~1.2g/cm3,and the thermal conductivity changed from 0.273W/(m•K) to 0.315 W/(m•K) at the 500 °C. It was found that the density of the sintered samples was dependent both on the content of foaming agent and magnesia. With the help of magnesia, light-weight alumina-spinel refractories with good volume stability were prepared by foam method.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1003-1008
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1003
• Online since: June 2012
• Authors: Xiao Xing Li, Yuan Bing Li, Lei Zhao, Xu Yao, Ya Wei Li, Shu Jing Li, Zhi Hui Fan, Fang Liu
• Keywords: Alumina-Spinel, Foaming, Light Weight, Magnesia

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