SiC/SiAlON对原位SiC结合刚玉材料抗侵蚀性的影响

Effects of SiC/SiAlON Addition on Slag Resistance of In-situ SiC Bonded Corundum Materials

采用矾土基高铝刚玉为骨料,以电熔刚玉细粉、S i粉、S iC粉或S iA lON粉为基质料,用酚醛树脂为结合剂,试样于1450℃埋炭烧成后,制备了烧结良好的原位S iC结合刚玉复合材料;采用静态坩埚法研究了加入S iC或S iA lON对这种复合材料抗渣性的影响。结果表明:原位S iC结合刚玉材料具有良好的抗侵蚀性能,加入适量S iC或S iA lON后复合材料的抗侵蚀性进一步提高;原位S iC结合刚玉基材料抗侵蚀行为和机理为:熔渣侵蚀材料的过程是S iC和S iA lON等非氧化物先被氧化,然后其氧化产物S iO2和A l2O3与熔渣中的CaO和A l2O3以及材料基质中的A l2O3反应生成钙长石,材料被侵蚀;原位生成的S iC难被熔渣润湿,且填充在气孔中,堵塞了熔渣渗透的主要通道;加入S iC和S iA lON,材料中非氧化物的量明显增多,因此抗侵蚀性明显提高。

In-situ SiC bonded corundum composite materials have been prepared,using bauxite-based corundum,fused corundum fines,silicon and SiC/SiAlON powder as starting materials and resin as binder after firing the specimens at 1450 ℃ under carbon embedded condition.The effects of SiC/SiAlON addition on slag resistance of this composite by static crucible method have been studied.The results show the in-situ SiC bonded corundum materials possess good corrosion resistance and the corrosion resistance is further improved with appropriate SiC/SiAlON powder addition.The behavior and mechanism of in-situ SiC bonded corundum materials against slag resistance are slag corrosion behavior of these composite materials is that SiC and SiAlON are first oxidized and the oxidized product SiO2 and Al2O3 will react with CaO and SiO2 from the slag and Al2O3 in the matrix of the specimens to form anorthite（CaO·Al2O3·2SiO2） and this material is corroded.The good corrosion resistance of this composite due to the in-situ formed SiC with poor wettability to blast furnace slag and SiC whiskers or particles fill in the pores to retard the slag infiltration into the inner.The nonoxides increase with SiC/SiAlON addition resulting in corrosion resistance being improved noticeably.