The corrosion behavior of 4 kinds of Al2O3-SiO2 castables by molten aluminum alloy was investigated using crucible method.Phase compositions and microstructures of the corroded crucible specimens were analyzed by XRD,SEM and EDXA.The experimental results indicate that:(1) In range of the testing temperatures,the specimens display a some degree sinter from the judgment of their porosity after firing at 1 200 ℃.Modulus of rupture (MOR) and cold crushing strength (CCS) of the specimens are increased with an increase of the treatment temperature.(2) Corrosion behavior of the castable is closely related to Al2O3 content and apparent porosity of the specimens,the higher the Al2O3 content is and the lower the porosity is,the better the penetration and the corrosion resistance of the specimens is.Aluminum alloy liquid react with SiO2 to form Al2O3 and Si at 850 ℃,and accompanying with volume shrinkage,which will lead to cracking of the refractory lining.(3) In reaction layer of the specimen particle boundary is fuzzy,and the erosion area appear denser,that will result in structural spalling under intermittent working condition.At same time,the Zn vapor remove from aluminum alloy liquid and enrich in boundary of transition layer.%采用坩埚法研究了铝合金液对4种铝硅质耐火浇注料的侵蚀行为,用XRD、SEM和能谱对侵蚀后的坩埚试样进行了物相和显微结构分析.结果表明:在本实验温度范围内,从气孔率判断,在1 200℃热处理后试样有一定程度的烧结,常温抗折和耐压强度均随处理温度的上升而增大;浇注料的抗铝液侵蚀性与其Al2O3含量和显气孔率密切相关,Al2O3含量越高、气孔率越低的试样抗渗透和抗侵蚀性能较好;铝合金液在850℃时与耐火材料中的SiO2反应生成Al2O3和Si,伴随体积收缩,导致耐火材料开裂损毁;耐火材料反应层中颗粒和基质均被侵蚀,侵蚀后气孔被填充变得更加致密,在间歇式工况条件下容易产生结构剥落.同时,侵蚀过程中,铝合金液中的Zn蒸汽逸出,在过渡层富集.
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