Influence of Quantity and Quality of Bonding Phases on Strength of Iron Ore Sinters

Sinter is the main raw material of blast furnaces, and its strength influences its running condition. Nevertheless, there is no comprehensive definition of the influencing mechanisms of the strength of the sinter. In this paper, the influences of the quantity and quality of the bonding phase on the strength of the sinter were investigated by changing the sintering parameters, such as the maximum sintering temperature, the binary basicity of adhering fines, holding time at high temperature, and types of core ores. As the maximum temperature increased from 1240 °C to 1320 °C and the binary basicity of the adhering fines increased from 5.0 to 9.0, and the strength of the sinter increased first and then decreased. The strength of the sinter was improved by increasing the holding time at high temperatures and reducing the melt absorbability of core ores. The strength of the sinter was comprehensively influenced by the strength of the bonding phase, the fluidity of the original melt, and the melt absorbability of core ores. There is a multivariate linear relationship between them. Moreover, the fluidity of the original melt had the greatest effect on the strength of the sinter, followed by the strength of the bonding phase, and the melt absorbability of core ores was the smallest.