SiO_2-Al_2O_3-CaO-MgO系夹杂物低熔点区域优化及控制的热力学计算  

Thermodynamic Calculations on Low Melting Point Area of SiO_2-Al_2O_3-CaO-MgO Inclusion and Its Control

作　　者：张博[1,2] 王福明[1,2] 李长荣[3] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]北京科技大学生态与循环冶金教育部重点实验室,北京100083 [3]北京科技大学材料科学与工程学院,北京100083

出　　处：《钢铁》2011年第1期39-44,共6页Iron and Steel

基　　金：国家自然科学基金项目(50874007);北京市教育委员会共建项目专项资助

摘　　要：为了预测CaO-Al2O3-SiO2-MgO系夹杂物具有良好变形能力的成分控制范围,首次通过热力学软件Fact-Sage对CaO-Al2O3-SiO2-MgO系液相投影图、低熔点区域大小进行了计算分析,并以阀门弹簧钢60Si2CrA为例,对CaO-Al2O3-SiO2-MgO系低熔点夹杂物的生成条件进行了探讨。结果表明：MgO和Al2O3含量分别为15%和20%时,夹杂物的低熔点区域最大。若使60Si2CrA弹簧钢液中的夹杂物成分落在CaO-SiO2-Al2O3-15%MgO系和CaO-SiO2-20%Al2O3-MgO系的低熔点区域,同时保证[O]含量尽可能低,则钢液中[O]和[Al]质量分数应分别控制在（10-30）×10^-6、（10-45）×10^-6和（10-30）×10^-6、（15-40）×10^-6。In order to predict the composition range of CaO-Al2O3-SiO2-MgO inclusion with good deformability,the liquidus projection and the low melting point area size of CaO-Al2O3-SiO2-MgO system was first calculated and analyzed by thermodynamic software FactSage.Furthermore,the condition of forming CaO-Al2O3-SiO2-MgO inclusions with low melting point was thermodynamically discussed in case of valve spring steel 60Si2CrA.The results show that the low melting area of CaO-Al2O3-SiO2-MgO inclusion is the biggest when the content of MgO and Al2O3 is 15% and 20%,respectively.If the inclusions composition fell on the low melting point area in CaO-Al2O3-SiO2-15%MgO system and CaO-Al2O3-SiO2-15%MgO system for 60Si2CrA steel,respectively,and then it also guarantee that [O] content is as low as possible,while the [O] and content in molten steel is（10-30）×10^-6 and（10-45）×10-6,（10-30）×10^-6 and（15-40）×10^-6,respectively.

关 键 词：CaO-SiO2-Al2O3-MgO系夹杂物 低熔点区域 60Si2CrA阀门弹簧钢 热力学计算 

分 类 号：TF701.2[冶金工程—钢铁冶金]