Effect of the Kinds of Aggregates and Sintering Temperature on the Properties of Lightweight Refractory Castables
Refractories consist of aggregates and matrices.Traditionally, Al2O3-SiO2 castables were prepared using dense mullite as aggregates.Actually, aggregates with high dense may not always be necessary because the matrix is usually more vulnerable to external force,so, the lightweight Al2O3-SiO2 castables with lower thermal conductivities which using porous aggregates instead of traditional dense ones have attracted much attention.In order to improve the properties of Al2O3-SiO2 castables, two kinds of porous Al2O3-SiO2 aggregates were introduced simultaneously into castables, one is prepared from different pore-making agent, and the other is different sintering temperature.The influence of particle sizes and grains content on the properties of the castables with dense aggregates have been widely studied, but the influence of addition of pore-making agent and sintering temperature on the castables containing porous Al2O3-SiO2 aggregates has not been investigated.In this research, the effect about addition of pore-making agent and sintering temperature on the apparent porosity, bulk density, strength and microstructure of lightweight castables prepared from insulators waste powders and aggregates were investigated by scanning electron microscopy (SEM)and YES-200 compression testing machine, etc.Thermal conductivity of the sintered specimens was tested by a hot plate apparatus (PBDR-02, Precondar,China).It was found that specimens of group HA-2 showed better complex properties as sintered at 1400 ℃.Among the best complex properties, apparent porosity, bulk density, cold modulus rupture, cold crushing strength was 46.3 %, 1.52 g/cm3, 7.1 Mpa and 26.9 Mpa, respectively.Thermal conductivities were 0.414, 0.423 and 0.455 w·m-1 ·k-1 at 300, 600 and 900 ℃, respectively.At the sintering temperature of 1400 ℃, the width of transition layer between aggregates and matrix in specimens H continued to shrunk to 30 μm.The increase of sintering temperature can promote the interface between aggregate and matrix, to hence the strength of the sample.
insulators waste lightweight castables microstructure properties
XU Nana LI Yuanbing LI Shujing
State Key Laboratory of Refractories and Metallurgy,Department of Materials Science and Engineering Wuhan University of Science and Technology (WUST),Wuhan,430081,P.R.China
国际会议
西安
英文
1-5
2016-09-20（万方平台首次上网日期，不代表论文的发表时间）