Effect of Steel Slag on Crystallization and Bending Strength of Glass Ceramics Based on Blast Furnace Slag

Abstract

The glass ceramics based on steel slag and blast furnace slag presented light-khaki color to deep-brown color with increasing content of steel slag. The major crystalline phase is gehlenite (Ca2Al2SiO7) with minor akermanite phase (Ca2MgSi2O7) for all the samples. Decreasing Al2O3 and increasing Fe2O3 in the samples increased glass viscosity, and decreasing SiO2 decreased the amount of liquid phase. Both the above effects result in the increasing optimum sintering temperature. The grain size and amount of crystalline phase were increased with content of steel slag. The bending strength of the samples first increases with content of steel slag up to a maximum 90 MPa, then decreases. The bulk density of the samples decreases with increasing content of steel slag, from 2.76 g/cm3 to 2.60 g/cm3, owing to lower content of glass phase during sintering process. The samples exhibit good chemical resistance, and the weight loss values in alkali are lower than those in acid. Therefore, the glass ceramics based on steel slag and blast furnace slag may have great potential for applications as building decorative materials, and it provides a promising way for the utilization of steel slag.

Preparation and properties of anorthite‐based ceramics by using metallurgical solid waste and fly ash

“…For sample A4 without pyrophyllite, its bending strength is lower than those of other samples at the same sintering temperature, and the maximum bending strength reaches 45.43 MPa at 1160°C. The reason may be that the removal of pyrophyllite led to decrease in ceramics viscosity and easier nucleation and growth of pores, resulting in a reduction in bending strength 19 …”

“…The bending strength of samples A2 and A3 increases gradually below 1150 • C and then decreases, this is because the ceramics have been over burned at 1160 The reason may be that the removal of pyrophyllite led to decrease in ceramics viscosity and easier nucleation and growth of pores, resulting in a reduction in bending strength. 19 At the same sintering temperature, the fly ash content has an obvious effect on the properties of ceramics after 1140 • C. At the same time, the pozzolanic activity of fly ash and the Al 2 O 3 provided by fly ash could increase the amount of alkaline and earth-alkaline oxides, change the ratio of SiO 2 :Al 2 O 3 , and make ceramic liquid phase sintering, so as to improve the properties of solid waste-based ceramics. 20…”