The Reaction Mechanism between Al-Al2O3-MgO· Al2O3 Composites Refractory and RH slag

摘要

Refractories on RH refining furnace work in the hot high temperature above 1600 °C,it will not only put up with the large weight of the load,but also need to resist the slag of molten iron as well as the corrosive atmosphere of high temperature.RH vacuum device is mostly lined with more magnesia chrome material,which causes great harm to the environment,so the development of refractory is hampered that calls for less chromium.White fused alumina (3-1mm,1-0mm),fine fused spinel,and fine aluminum were added as the start materials,with sodium hexametaphosphate as binder,Al-MgAl2O4-Al2O3 composite samples are made by taking a chemical combination.Design 5 samples,which were compared to determine the optimal scheme with the content change of fine aluminum (0wt.％,2 wt.％,4 wt.％,6 wt.％,8 wt.％,respectively).Static crucible method was taken to test the performance of its resistance behavior to RH refining slag Through the investigation of its SEM microstructure and percentage of the erosion area and the penetration area,the following conclusions could be summarized:Basic RH slag attack of the composite is mainly through the erosion and infiltration caused by CaO、SiO2,and clear stratification appeared near the sample workface.The samples of each samples generally showed good resistance to slag penetration,and the addition of Al can effectively improve the slag erosion resistance.CA,which appeared as the shape of palisade,generated in the transition zone,by the reaction of slag and corundum,and it could protect the composite from slag erosion and reducing the slag erosion area.The Al power,added as a metal plastic phase,still exists at high temperatures,increasing the liquid in the system,to alleviate heat stress and improve the slag resistance of composites.