Preparation And Properties Of Penetration And Corrosion Resistance Castable To The Aluminum Melt

In order to solve some practical problems such as poor property of resisting penetration and corrosion to aluminum liquid of castable,which is difficult to overcome in the aluminum melting furnace,the object of study is prepared castables with good property of penetration and resistance to aluminum melt,based on the high bauxite as the main material,the effects of particle gradation on the physical properties,strength properties and resistance to aluminum melt properties were investigated under the two critical particle sizes of castables,and the optimum particle gradation was obtained.Under the optimum particle gradation,the influences of four kinds of auxiliary materials of silica fume,MA spinel,barium sulfate and cement to physical indexes,strength indexes and the indexes of resisting aluminum melt corrosion performance were discussed by orthogonal test.And on the basis of orthogonal experiment,the influence of high aluminum fine powder of castable on the erosion resistance of aluminum melt was discussed,and the optimum dosage and optimum ratio of fine powder were determined.The mineral composition of the castable sample matrix and microstructure were analyzed by means of XRD and SEM.And finally compared with the currently used castables.Research indicates:(1)If the castable is graded with the critical particle size DL = 8mm and DL = 5mm,the optimum particle gradation coefficients are q = 0.28 and q = 0.37,respectively.The performance of the castable especially the property of aluminum melt corrosion resistance was better than that of other gradients,and the performance of two particle gradation are similar.(2)The composition of castable matrix affect its physical properties,strength properties and resistance to aluminum melt erosion performance to a certain extent.From the view of phase composition,when the matrix exist CA2 phase,the performance of aluminum melt erosion resistance was terrible,and the presence of barium feldspar and MA spinel phase in matrix can improve the aluminum melt erosion resistance of castable.(3)When the different types of high-alumina fine powder are used in the matrix,the effect rule of the auxiliary material fine powder on the erosion resistance of aluminum melt were not changed.In contrast,when the high alumina powder is 88 bauxite fine powder,theanti-aluminum melt wetting,infiltration,erosion performance of castable was best.(4)The results showed that when the castable particles were graded with DL = 8mm,q= 0.28,the aggregate was 80 or 88 bauxite,the fine powder was 88 bauxite,the other powder was added as 5wt% of ?-Al2O3,3wt% of silica fume,3wt% of MA spinel,4wt% of barium sulfate,and 4wt% of cement,the castable would have excellent property of erosion resistance to aluminum melt.When the aggregate was 80 bauxite,mullite phase content in the aggregate was high,mullite would react with cryolite,could formed mattstone barrier layer between the aggregate surface and matrix material gap,so its anti-cryolite erosion performance is better than the castables which aggregate was 88 bauxite.