IF钢生产过程中Al-Ti-Mg-O类夹杂物的演变行为
|
摘要
采用扫描电镜和热力学分析,对IF钢生产过程中Al-Ti-Mg-O类夹杂物的成分、尺寸和形貌的特征及演变行为进行了研究。结果表明,RH脱氧后夹杂物主要为纯Al_2O_3,合金化以后到浇铸成连铸坯的过程中夹杂物中Al_2O_3占比不断减小,含Ti类和含Mg类夹杂物占比不断增加;纯Al_2O_3夹杂尺寸较大,含Ti夹杂物尺寸较小。在热力学平衡条件下,钢中的夹杂物应为Al_2O_3稳定存在,但二次氧化和局部Ti浓度的升高促进了TiO_x的生成。夹杂物中TiO_x含量的增加,将会降低Al-Ti-Mg-O类夹杂物熔点。
The evolution of chemical composition,size,proportion,and morphology of the Al-Ti-Mg-O inclusions during the steelmaking process of interstitial free(IF) steel were investigated by means of AutoSEM.Results showed that after RH deoxidation,the main inclusions were pure Al_2O_3 inclusions.Then the proportion of Al_2O_3 in inclusions decreased,while the proportion of inclusions containing titaniumand magnesium increased from RH deoxidation to slab.The size of pure Al_2O_3 inclusions was larger and the size of inclusions containing titanium was smaller.Thermodynamic analysis results showed that the inclusions should be stable with Al_2O_3 at the concentration of molten steel.But the titanium alloying and spontaneous enrichment would make a high titanium concentration environment that was in favor of the TiO_x existence.Moreover,more TiO_x component could control Al-Ti-Mg-O inclusions with a lower melting temperature.
The evolution of chemical composition,size,proportion,and morphology of the Al-Ti-Mg-O inclusions during the steelmaking process of interstitial free(IF) steel were investigated by means of AutoSEM.Results showed that after RH deoxidation,the main inclusions were pure Al_2O_3 inclusions.Then the proportion of Al_2O_3 in inclusions decreased,while the proportion of inclusions containing titaniumand magnesium increased from RH deoxidation to slab.The size of pure Al_2O_3 inclusions was larger and the size of inclusions containing titanium was smaller.Thermodynamic analysis results showed that the inclusions should be stable with Al_2O_3 at the concentration of molten steel.But the titanium alloying and spontaneous enrichment would make a high titanium concentration environment that was in favor of the TiO_x existence.Moreover,more TiO_x component could control Al-Ti-Mg-O inclusions with a lower melting temperature.
引文
[1]WANG M,BAO Y P.Source and negative effects of macroinclusions in titanium stabilized ultra low carbon interstitial free(Ti-IF)steel[J].Metals&Materials International,2012,18(1):29-35.
[2]BASU S,KUMAR C S,GIRASe N U.Nozzle clogging behaviour of Ti-bearing Al-killed ultra low carbon steel[J].ISIJ International,2004,44(10):1653-1660.
[3]WANG M,BAO Y P,ZHAO L H,et al.Distribution and detriment of bubbles in continuous casting interstitial free steel slab[J].ISIJ International,2015,55(4):799-804.
[4]栗红,孙群,吕志升,等.Mg合金在炼钢过程应用研究[J].上海金属,2015,37(6):69-72.
[5]BRAUN T B,ELLIOTT J F,FLEMINGS M C.The clustering of alumina inclusions[J].Metallurgical Transactions B,1979,10(2):171-184.
[6]KIKUCHI N,NABESHIMA S,KISHIMOTO Y,et al.Effect of Ti de-oxidation on solidification and post-solidification microstructure in low carbon high manganese steel[J].ISIJ International,2007,47(9):1255-1264.
[7]REN Y,ZHANG L,YANG W,et al.Formation and thermodynamics of Mg-Al-Ti-O complex inclusions in Mg-AlTi-deoxidized steel[J].Metallurgical&Materials Transactions B,2014,45(6):1-15.
[8]WANG M,BAO Y P,CUI H,et al.The composition and morphology evolution of oxide inclusions in ti-bearing ultra lowcarbon steel melt refined in the RH process[J].ISIJ International,2010,50(11):1606-1611.
[9]KARASANGABO A,BERNHARD C Investigation of alumina wetting by Fe-Ti,Fe-P and Fe-Ti-P alloys[J].Journal of Adhesion Science&Technology,2012,26(8/9):1141-1156.
[2]BASU S,KUMAR C S,GIRASe N U.Nozzle clogging behaviour of Ti-bearing Al-killed ultra low carbon steel[J].ISIJ International,2004,44(10):1653-1660.
[3]WANG M,BAO Y P,ZHAO L H,et al.Distribution and detriment of bubbles in continuous casting interstitial free steel slab[J].ISIJ International,2015,55(4):799-804.
[4]栗红,孙群,吕志升,等.Mg合金在炼钢过程应用研究[J].上海金属,2015,37(6):69-72.
[5]BRAUN T B,ELLIOTT J F,FLEMINGS M C.The clustering of alumina inclusions[J].Metallurgical Transactions B,1979,10(2):171-184.
[6]KIKUCHI N,NABESHIMA S,KISHIMOTO Y,et al.Effect of Ti de-oxidation on solidification and post-solidification microstructure in low carbon high manganese steel[J].ISIJ International,2007,47(9):1255-1264.
[7]REN Y,ZHANG L,YANG W,et al.Formation and thermodynamics of Mg-Al-Ti-O complex inclusions in Mg-AlTi-deoxidized steel[J].Metallurgical&Materials Transactions B,2014,45(6):1-15.
[8]WANG M,BAO Y P,CUI H,et al.The composition and morphology evolution of oxide inclusions in ti-bearing ultra lowcarbon steel melt refined in the RH process[J].ISIJ International,2010,50(11):1606-1611.
[9]KARASANGABO A,BERNHARD C Investigation of alumina wetting by Fe-Ti,Fe-P and Fe-Ti-P alloys[J].Journal of Adhesion Science&Technology,2012,26(8/9):1141-1156.