Abstract：In order to explore the influence mechanism of the non-reactive component BaO on the microstructure stability and macroscopic properties of aluminate slag, the influence of BaO on the melting temperature, viscosity, electrical conductivity and microstructure of aluminate slag (w(CaO)/w(Al2O3)=1.3) was studied by combining hemisphere melting temperature test, rotating viscometer, conductivity tester with four-electrode technique and infrared spectrum experiment. The results show that, with the increase of BaO content, BaO simplifies the microstructure network structure of aluminate slag, and the degree of polymerization of the aluminate slag structure decreases. Because the melting temperature of the slag changes very little within the composition range of this test, it shows that the degree of superheat has little effect on the viscosity of the slag, that is, the viscosity of the slag is mainly affected by the degree of polymerization. Due to the increase of the Ba2+ cation concentration and the decrease of the polymerization degree of the slag network structure, the conductivity of slag increases. In addition, with the increase of BaO content, the breaking temperature on the viscositie-temperature curve decreases, indicating that BaO improves the glass properties of the slag at low temperature. Therefore, BaO is beneficial to the improvement of the lubricating properties of aluminate-based mold slag.
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2021, Vol. 40 
