Study On The Metallurgical Properties Of CaO-Al₂O₃ Mold Slag For High Aluminum High Manganese Steel

The traditional CaO-SiO₂ based mold fluxes will react with [Al]+SiO₂=Al₂O₃+[Si] during slag and steel production in high alumina and high manganese steel,resulting in the fluctuation of mold fluxes,which is not easy to control,deteriorate performance and affect continuous casting production.Therefore,the research of CaO-Al₂O₃ based high aluminum high manganese steel slag metallurgical properties provides a theoretical basis for the high aluminum high manganese steel casting production and slag design.Through the analysis of thermodynamics and oxygen potential diagram calculation,based on the "non reactive slag" design principle,the Na2 O,Li2O,Ca F2,Mg O and Ba O are determined as protective slag additive;through the calculation of Factsage slag liquid region,component content range was determined,and designed six factors and five levels orthogonal experiment scheme.On the design of mold slag is study on the physical and chemical properties,and the results showed that the effect of flux on the melting temperature and viscosity were increased with the increase of the content of the added decreased;for 3#,4#,5#,19#,20# and 23# six groups of formula of slag crystallization characteristics,and mineral analysis.The results showed that 3#,4#,19# and 23# four group formula protective slag metallurgical characteristics suitable for crystallization product with borate?Ca3B2O6,Mg2B4O7?,a small amount of Na F.The main precipitation product is Ca3B2O6,and the precipitation temperature is between 1198?⁹36?.The dissolution behavior of Al₂O₃ in CaO-Al₂O₃ based on slag system is studied from three aspects: the diameter of Al₂O₃ rod,the temperature and the chemical composition of mold fluxes.The mineralogical situation of mold fluxes after testing is analyzed by the software Factsage.The experimental results showed that the amount of Al₂O₃ dissolved by molten slag increases with the increase of Al₂O₃ rod diameter and temperature,and decreases with the increase of Al₂O₃ content and viscosity of slag itself.The dissolution rate of Al₂O₃ rods is the largest at the interface of molten slag.