| CaO-Al2O3-SiO2 glass ceramic is one of the most promising high-grade decoration materials all over the world because of its excellent performances. But the corrosion mechanism of the glass ceramic to refractories has not been investigated, which is critical to improve the quality of the CaO-Al2O3-SiO2 glass ceramic, prolong the span of the glass furnace and lower the manufacture cost.In this paper, Various effective means are taken to study the corrosion mechanism. Compared with the ordinary Na2O-CaO-SiO2 glass, the relationship of the glass ceramic composition and the meltingtemperature with the corrosion degree of the various refractories is discussed in detail. The microstructure and characteristics of each kind of refractory's matrice and keacting layer are analysized and a great amount of optical microphotographs are obtained, which may provide reliable theory basis to manufacture the glass ceramic.The results have been got as follows.(1) The purpose of this paper and the present research status of the glass ceramic and its corrosion to the refractory are in troduced briefly.(2) The experiments of the refractory's anti-corrssion in static condition are designed according to the nation's criterion.(3) The microstructure of the refractories before and after being corroded as well as the changing features have been studied by applying the large-size optical microscope, SEM and EPMA.The whole article provide 80 pieces of pictures. Which are very useful to provide the theoretical basis to research the mechanism corrosion.(4) Combining XRD diffraction in qualitative and the optical microscope, the composition of the refractories before and after being corroded is identified, which is very advantageous to identify the reaction and the corrosion mechanism.(5) The relationship of microstructure with anti-corrosion of the refractories has been analyzed.(6) Comparing the corrosion function of the CaO-Al2O3-SiO2 glass ceramic with that of the Na2O-CaO-SiO2 ordinary glass, it is found out that Na2O-CaO-SiO2 ordinary glass corrode the refractories more seriously. And the corrosion of AZS brick is always taking place at the liquid curve, while the corrosion of white afrodite is the more downward the more serrous.(7) Experiments show that the sequence of the anti-corrosion of the three chosen refractories is that AZS brick >white afrodite >clay brick.(8) The mechanism of CaO-Al2O3-SiO2 glass ceramic corroding the AZS brick is that the glass phase and the corundum in eutectic crystallization are melted and corroded by matrix firstly. Secondly, the liquid glass get inside and tine the baddeleyite in the meantime, the corudem separate out to react with the CaO-Al2O3-SiO2 glass ceramic and produce anorthite and gehlenite, and so on. Lastly, the AZS brick is washed away.(9) The mechanism of CaO-Al2O3-SiO2 glass ceramic corroding the white afrodite is that the composition itself is melted and corroded at high temperature and results in the polymorphic transformation and separates out cristobalite to form a lot of cracks, then it react with the liquid glass to produce new minerals, lastly, the white afrodite is melted and washed out.(10) The extent of corrosion will change if the composition of the CaO-Al2O3-SiO2 glass ceramic changes. As the content of CaO, BaO and ZnO in the glass ceramic is increased, the extent of corrosion is increased.The mechanism of the CaO-Al2O3-SiO2 glass ceramic corroding the refractories is complicated, because it involves science of glass and science of refractory, which is a very hard work. But its application is very wide. The raising and carrying out this research is the first time, but the research is not perfect and must be improved.
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