Evaluation of CaO-SiO2 Based Mold Flux for Medium Mn Steel
Interfacial reaction between CaO-SiO2 based mold flux and Mn in molten steel during casting of medium and high Mn steels would change compositions and properties of slags,which leads to severe casting problems such as poor lubrication,uneven heat transfer,and surface defects.In this study,the effect of basicity (CaO/SiO2) on the MnO accumulation in mold flux was examined through a laboratory experiment.Based on the results,a CaO-SiO2 slag system with basicity of 1.2 was applied in plant trial to cast medium manganese steel with 5 Mn.The flux samples were taken from liquid slag pool and solid slag layer during the casting process to investigate evolutions of composition and properties.The results show that appropriate increase of the basicity of mold flux was beneficial to reduce the MnO accumulation,though it was not a critical factor for the control of the reaction between SiO2 in mold flux and Mn in molten steel.It was found that about 4 % to 6 % MnO formed during the slag/steel interaction in plant trial.The concentration of MnO in liquid slag pool was higher than that in solid slag layer due to the nonuniform flow of flux in the meniscus.Viscosity of mold flux decreased with the increase of MnO content.The accumulation of MnO could inhibit the crystallization of mold flux and decrease the thickness of solid slag film,which may result in the excessive heat transfer rate from solidified shell to mold wall.
medium Mn steel mold flux lime-silica MnO accumulation
YANG Jie CAI Zhaozhen LI Yezhong ZHU Miaoyong
School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China Anshan Iron and Steel Group Corporation, Anshan 114021, Liaoning, China
国际会议
成都
英文
298-301
2016-11-16（万方平台首次上网日期，不代表论文的发表时间）