Research On Corundum Based Dispersive Purging Plugs

Purging plugs is the most important functional refractories for the ladle blowing argon from bottom.Dispersive purging plugs have high working reliability,safety and economy,but their low strength and poor scour resistance restrict their application.The effect of particle size on the properties of corundum based dispersive purging plugs was studied based on the Andreasen distribution equation.Studies have shown that when the value of q is 0.49,the particle packing deviates from the tightest packing,ensuring good air permeability.At this time,replacing theα-Al₂O₃micropowder with d₅₀=3μm withα-Al₂O₃micropowder with d₅₀=0.6μm can improve the normal and high temperature strength of the material,but it has an adverse effect on the gas permeability of the material.In order to further improve the performance of the dispersive purging plugs,this paper uses nano-Ca CO₃,Cr₂O₃micropowder,Zr O₂micropowder,nano-Mg CO₃as additives to study the effect of different types of additives and their additions on the performance of the dispersive purging plugs.The research shows that:（1）Ca O generated by the decomposition of Ca CO₃at high temperature reacts with Al₂O₃to form CA₆,which improves the strength of the material at room temperature and high temperature.In order to ensure better slag resistance,it is more appropriate to add 1.5%（w）nano-Ca CO₃;（2）Cr₂O₃is not easily wetted by molten steel,and the introduction of Cr₂O₃micropowder can effectively improve the slag resistance of the material.In order to ensure good air permeability,it is more appropriate to add 6%（w）Cr₂O₃micropowder;（3）An appropriate amount of Zr O₂micropowder can promote the dense structure of the material The introduction of Zr O₂micropowder can improve the strength of the material at room temperature and high temperature.In order to ensure good air permeability,it is suitable to add 3%（w）Zr O₂micropowder;（4）Mg CO₃decomposed into Mg O at high temperature and released CO₂,which improved the apparent porosity of the materials and improved the permeability of the materials.In order to ensure higher strength at room temperature and high temperature and good slag resistance,it is more appropriate to add 1%（w）of nano-Mg CO₃.Figure 78;Table 14;Reference 109...