Preparation And Study Of Glass-ceramics Based On Converter Slag

Steel slag is a kind of solid waste from iron and steel enterprises in the smelting process, it have a higher emissions, about 12% to 20% of crude steel production, according to the different furnace, steel slag is generally divided into the converter slag, flat slag and electric slag, converter slag in China accounts for about 65% of the total. The traditional focus on comprehensive utilization of steel slag for cement raw materials, or for road construction materials, there is a low utilization rate and additive value.In this paper, Baotou Steel Co. converter slag as raw material, adding a certain amount of CaF2 as flux, utilizing large Fe₂O₃ (FeO) and a small amount of TiO2 in converter slag as nucleating agents, slag glass-ceramic were prepared by melting method with augite as principal crystalline phase, the size of crystal is about 0.2μm.The crystallization behavior and microstructure of converter glass-ceramics were studied by DSC, XRD and SEM. Along with the increase of the content of the converter slag and ZnO, the properties of products changed. By means of orthogonal testing method,the effect of the heat treatment parameter on the bending strength was discussed. Accordingly, the optimal heat treatment was determined.Experimental results show that the content of converter slag have an significant effects on the crystallization ability of parent glass, the phase composition and mechanical properties of glass-ceramics. The increase of the content of converter slag is beneficial for the crystallization of base glass and improve the performance of ceramics, the introduction of converter slag volume can reach more than 50wt.%. ZnO can improve the bending strength and change the main crystalline phase of glass-ceramics, 3wt.% to introduce is enough for base glass.Heat treatment has a certain influence on the bending strength of glass-ceramic, the most important is the crystallization temperature, and the nucleation temperature is least. Optimal heat treatment should be heating to 625℃at a rate of 6℃/ min holding for 2h, and then heating to 860℃at a rate of 3℃/ min holding for 2h or 6h.