AOD精炼双相不锈钢2101去碳保铬研究  

Decarburization and chromium retention of AOD-refined duplex stainless steel 2101

作　　者：易天龙 吴华杰 孙悦 刘颖辉 YI Tian-long;WU Hua-jie;SUN Yue;LIU Ying-hui(Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学钢铁共性技术协同创新中心,北京100083

出　　处：《工程科学学报》2020年第S01期89-94,共6页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(U1660113)。

摘　　要：双相不锈钢2101生产成本低,性能优异,近年来被逐渐重视.采用“电炉+AOD+模铸”的工艺生产2101双相不锈钢,在AOD精炼过程中,研究了温度和主要成分Cr、C、Si的变化情况,结果显示,AOD炉有很好的脱碳效果,能将C质量分数(w[C])由2.5%脱至0.03%以下,在还原期,Si对Cr有很好的还原效果.精炼过程中,最重要的是脱碳,但将碳脱至0.1%以后,所需要的条件变得苛刻.通过热力学计算公式,研究了双相不锈钢2101去碳保铬的影响因素,结果表明,碳铬平衡主要受CO分压和温度的影响,CO分压越低、温度越高越有利于脱碳.在CO分压一定,w[C]<0.1%时,w[C]越低,碳铬平衡曲线的斜率越大,脱碳需要的温度越高,脱碳越困难,降低CO分压可进一步脱碳.在PCO/P0=0.4,w[Cr]=21.5%条件下,为将w[C]脱至0.03%以下,需要将炉内温度升到1746.1℃以上.Duplex stainless steel 2101 has low production cost,excellent performance,and good resistance to NaCl corrosion.Duplex stainless steel 2101 can be used as marine stainless steel.In recent years,duplex stainless steel 2101 has been considered a valuable material.The“electric furnace+argon oxygen decarburization(AOD)+die casting”process was used to produce duplex stainless steel 2101.During the AOD refining process,the changes of temperature and Cr,C,and Si contents were investigated.Results show that the AOD furnace has a good decarburization effect.The C content(mass fraction)decreases from 2.5%to<0.03%.During the reduction period,Si has a good reduction effect on Cr.During the refining process,the most important step is decarburization.However,after decarbonizing to 0.1%,the required conditions become harsh.The factors affecting the decarburization and chromium retention of duplex stainless steel 2101 were analyzed using thermodynamic calculation formulas.The results show that the carbon–chromium balance is mainly affected by CO partial pressure and temperature.The lower the CO partial pressure,the higher the temperature,which is favorable for decarburization.When the CO partial pressure is constant and w[C]<0.1%,the slope of the carbon–chromium equilibrium curve is increasing rapidly with the w[C]value decreasing.It means that the increased temperature range becomes larger making decarbonization more difficult,and the lower CO partial pressure is required for further decarburization.Further decarburization under the conditions of PCO/P0=0.4 and w[Cr]=21.5%is conducted.To reduce w[C]to<0.03%,the temperature in the furnace needs to be increased over 1746.1℃.

关 键 词：双相不锈钢 AOD 去碳保铬 温度 CO分压 

分 类 号：TF764+.1[冶金工程—钢铁冶金]