熔炼Fe-Si-B合金的中频感应炉用石英捣打炉衬的损毁机制

Damage mechanism of quartz ramming lining for medium frequency induction furnaces melting Fe-Si-B alloy

以天然石英和熔融石英为原料,加入硼酐捣打成熔炼Fe-Si-B合金的无芯感应炉衬,研究了该石英质炉衬的损毁机制。结果表明:炉衬服役后烧结层会产生含Fe氧化物的渗透层;渗透层中Fe的氧化物会与SiO_2反应使炉衬原有网状结构遭到破坏,同时还会伴随体积效应加大内部应力使裂纹扩展,造成烧结层强度进一步降低;炉衬下部损毁严重与烧结层强度降低及电磁搅拌引起的合金液对炉衬冲蚀和磨损有关; 1 350～1 380℃下,Fe-Si-B合金熔体中Al会与SiO_2反应侵蚀炉衬,但侵蚀程度有限。

The lining of coreless induction furnaces for melting Fe-Si-B alloy was rammed using natural quartz and fused quartz as main starting materials,and adding boric anhydride.The damage mechanism of the lining was studied.The results show that the sintered layer produces a permeation layer containing Fe oxides when the lining serves.The Fe oxides react with SiO2,which destroys the original network structure of the lining,meanwhile,and increases the internal stress accompanied by the volume effect,expanding the crack and further reducing the sintered layer strength.Serious damage of the lining lower part is related to the strength reduction of the sintered layer and the lining erosion and wear caused by electromagnetic stirring of the alloy melt.Al in the melt of Fe-Si-B alloy reacts with SiO2 to erode the lining with limited degree from 1 350℃to 1 380℃.