高铝TRIP钢连铸过程中保护渣中Al2O3含量的变化对渣膜传热的影响

摘要

高Al含量TRIP钢在连铸过程中钢液中的[Al]易与保护渣中的SiO2发生反应,使保护渣中Al2O3含量从3%快速增加至30%左右,导致保护渣的传热性能发生改变,影响连铸坯的质量和连铸工艺操作.利用结晶器保护渣渣膜热流模拟仪研究Al2O3含量对Al-TRIP钢保护渣传热的影响,并利用扫描电镜、X射线衍射仪分析渣膜的结晶相.结果表明:当Al2O3含量从3%增加到20%时,保护渣的热流密度显著降低;当保护渣的Al2O3含量从20%增加到30%时,保护渣的热流密度先增加后减少;随w(Al2O3)/w(SiO2)比值的增大热流密度逐渐降低,并且在本实验条件下保护渣中会析出CaF2晶体.%The high Al content Al-TRIP steel is likely to react with SiO2 in the mold slag during the continuous casting process, which leads to a rapid increase of Al2O3 content in the slag from 3％ to 30％. Sequentially, the characteristic of heat transfer through slag film is changed, which affects the quality of strand and process operation of continuous casting. The mold slag film simulator was used to investigate the effect of Al2O3 content on heat transfer of Al-TRIP steel of mold fluxes, and SEM and XRD were used to analyze the crystalline phase of the slag films. The results show that the heat flux density of the slag film increases significantly with the increase of Al2O3 content from 3％ to 20％, and the heat flux density initially increases then decreases again with the increase of Al2O3 content from 20％ to 30％. As the w(Al2O3)/w(SiO2) ratio increases, the heat flux decreases, and under this experiment condition, the CaF2 crystal phase precipitates.