In the process of glass-ceramics prepared with Baotou steel blast furnace slag, quartz sand, and other raw materials by melting method, the mutual influence of the special components such as CaF2, REXOY, TiO2, K2O, and Na2O in the blast furnace slag on the crystallization behavior of parent glass was investigated using differential thermal analysis (DTA) and X-ray diffraction (XRD). The results show that the special components in slag can reduce the crystallization temperature and promote crystallization of glass phase, which belongs to surface crystallization of glass, and they cannot play the role of the nucleating agent; the major crystal phase composed of diopside, diopside containing aluminum and anorthite, is slightly different from the expected main crystal phase of diopside. Therefore, the nucleating agents of proper species and quantity must be added into the raw materials in order to obtain glass-ceramics. The results have important theoretical guidance meaning for realizing industrial production of Baotou steel blast furnace slag glass-ceramics preparation. 1. Introduction Glass-ceramics are uniform polycrystalline materials with glasses and crystals, which are processed and formed as glasses and then converted into a crystalline ceramic by a subsequent heat treatment [1, 2]. It is of great significance to prepare glass-ceramics from blast furnace slag for improving utilization and added value of iron smelting slag, recovering heat of slag, increasing economic benefit of enterprises, and reducing environmental pollution [3–10]. Baotou steel blast furnace slag is unique in the world because it contains some special components such as CaF2, REXOY, TiO2, K2O, Na2O, and the radioactive element thorium [11]. Among them, CaF2 and TiO2 can act as nucleating agent to promote crystallization of glass [12–14], and K2O and Na2O can decrease the melting point of glass, but there are few reports so far regarding the effect of REXOY, Nb2O5, and ThO2 on the crystallization behavior of glass in the process of glass-ceramics prepared. These special components make the crystallization behavior of glass-ceramics prepared from blast furnace slag become more complex, and the related theory of glass-ceramics prepared from ordinary blast furnace slag is not completely applicable to Baotou steel blast furnace slag. Therefore, the mutual influence of the special components in Baotou steel blast furnace slag on the crystallization behavior of parent glass was investigated without any nucleating agents added in this paper. The results not only are a supplement to the
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