Effect of content of Al2O3 and MgO on crystallization of blast furnace slag during fiber formation

The simulation of blast furnace slag was prepared by pure chemical reagents. Test methods like DSC, XRD and SEM were used to study the effect of Al 2 O 3 and MgO content on crystallization of blast furnace slag during fiber formation. The results show that as Al 2 O 3 and MgO contents in the sample changed, blast furnace slag was crystallized at the average temperature below 1232 K. When the ratio of Mg/Al in the samples is 0.6 calculated by Kissinger equation, crystallization activation energy is at the maximum value and the system is in the most stable condition. The sample crystallization phases are mainly calcium akermanite (2CaO·MgO·2SiO 2 ) and gehlenite (2CaO·Al 2 O 3 ·SiO 2 ). Secondary crystallization phases are anorthite (CaAl 2 Si 2 O 8 ), wollastonite minerals (WOLLA) and pyroxene minerals (cPyrA). Meanwhile, the principal crystallization phases of the samples are different types and have different contents, and the microstructures of the sample sections are different due to the difference between MgO/Al 2 O 3 ratio.