工程科学学报
工程科學學報
공정과학학보
Journal of University of Science and Technology Beijing
2015年
11期
1415-1421
,共7页
郭宝奇%包燕平%王敏%林路
郭寶奇%包燕平%王敏%林路
곽보기%포연평%왕민%림로
炼钢%精炼%渣系%优化%液相线温度%夹杂物
煉鋼%精煉%渣繫%優化%液相線溫度%夾雜物
련강%정련%사계%우화%액상선온도%협잡물
steelmaking%refining%slag systems%optimization%liquidus temperatures%inclusions
通过对低碳含铝钢20Mn2精炼过程的取样分析,得出精炼渣的熔化温度偏高,渣中存在大量固相CaO,并导致钢中含有CaO类夹杂物,精炼渣吸附夹杂物能力差. 利用FactSage热力学计算,从渣的低熔点区域控制和渣-钢反应这两个方面对渣系进行研究与优化. 结果表明,CaO/Al2 O3 质量比在1. 5左右添加质量分数为3% CaF2 可以有效降低渣的熔化温度,渣的熔化温度随着CaF2 含量的升高呈现先降低后升高的趋势,MgO的质量分数控制5%左右低熔点区域面积达到最大. 在SiO2 质量分数大于30%区域,钢中氧含量大体上随着CaO/Al2 O3 质量比的增加而降低,在SiO2 的质量分数低于30%区域随着CaO含量的升高而降低,钢中酸溶铝含量在SiO2 含量高的区域随着Al2 O3/SiO2 质量比的增加而升高,在SiO2 含量低的区域随着CaO/SiO2 质量比的增加而增加. 根据热力学分析结果得出合理的渣系范围:CaO 50% ~60%, Al2 O3 20% ~35%, SiO2 5% ~10%, MgO 5% ~8%, CaF2 0~5%. 优化渣系的实验结果表明,优化后渣系熔化温度降低,钢中夹杂物数量、面积和平均尺寸均有明显下降.
通過對低碳含鋁鋼20Mn2精煉過程的取樣分析,得齣精煉渣的鎔化溫度偏高,渣中存在大量固相CaO,併導緻鋼中含有CaO類夾雜物,精煉渣吸附夾雜物能力差. 利用FactSage熱力學計算,從渣的低鎔點區域控製和渣-鋼反應這兩箇方麵對渣繫進行研究與優化. 結果錶明,CaO/Al2 O3 質量比在1. 5左右添加質量分數為3% CaF2 可以有效降低渣的鎔化溫度,渣的鎔化溫度隨著CaF2 含量的升高呈現先降低後升高的趨勢,MgO的質量分數控製5%左右低鎔點區域麵積達到最大. 在SiO2 質量分數大于30%區域,鋼中氧含量大體上隨著CaO/Al2 O3 質量比的增加而降低,在SiO2 的質量分數低于30%區域隨著CaO含量的升高而降低,鋼中痠溶鋁含量在SiO2 含量高的區域隨著Al2 O3/SiO2 質量比的增加而升高,在SiO2 含量低的區域隨著CaO/SiO2 質量比的增加而增加. 根據熱力學分析結果得齣閤理的渣繫範圍:CaO 50% ~60%, Al2 O3 20% ~35%, SiO2 5% ~10%, MgO 5% ~8%, CaF2 0~5%. 優化渣繫的實驗結果錶明,優化後渣繫鎔化溫度降低,鋼中夾雜物數量、麵積和平均呎吋均有明顯下降.
통과대저탄함려강20Mn2정련과정적취양분석,득출정련사적용화온도편고,사중존재대량고상CaO,병도치강중함유CaO류협잡물,정련사흡부협잡물능력차. 이용FactSage열역학계산,종사적저용점구역공제화사-강반응저량개방면대사계진행연구여우화. 결과표명,CaO/Al2 O3 질량비재1. 5좌우첨가질량분수위3% CaF2 가이유효강저사적용화온도,사적용화온도수착CaF2 함량적승고정현선강저후승고적추세,MgO적질량분수공제5%좌우저용점구역면적체도최대. 재SiO2 질량분수대우30%구역,강중양함량대체상수착CaO/Al2 O3 질량비적증가이강저,재SiO2 적질량분수저우30%구역수착CaO함량적승고이강저,강중산용려함량재SiO2 함량고적구역수착Al2 O3/SiO2 질량비적증가이승고,재SiO2 함량저적구역수착CaO/SiO2 질량비적증가이증가. 근거열역학분석결과득출합리적사계범위:CaO 50% ~60%, Al2 O3 20% ~35%, SiO2 5% ~10%, MgO 5% ~8%, CaF2 0~5%. 우화사계적실험결과표명,우화후사계용화온도강저,강중협잡물수량、면적화평균척촌균유명현하강.
Through analysis of samples taken in the refining process of low carbon and aluminum containing 20Mn2 steel, it was found that the melting point of the refining slag was high, substantial solid CaO and CaO-type inclusions existed in the steel and slag, leading to a decrease in absorption capacity of inclusions in the molten slag. Based on thermodynamic calculations utilizing FactSage software, the slag system was investigated and optimized by integrating the control of low-melting-point regions and reactions between slag and steel. The results show that 3% CaF2 addition can decrease the melting temperature of the slag with CaO/Al2O3 mass ratio around 1. 5, and the melting point of the slag exhibits an initial decline and a subsequent rise with increasing CaF2 content. The largest low-melting-point region is obtained through governing the MgO content in a vicinity of 5%. The oxygen content in the steel decreases with increasing CaO/Al2O3 mass ratio in the region of SiO2 exceeding 30%, and decreases with increasing CaO content in the region of SiO2 lower than 30%. The acid-soluble aluminum content increases with increasing Al2O3/SiO2 mass ratio in the region of high SiO2 content and increasing CaO/SiO2 mass ratio in the region of low SiO2 content. According to results from thermodynamic analysis, the optimized slag can be given as 50% -60% CaO, 20% -35% Al2O3 , 5% -10% SiO2 , 5% -8% MgO, and 0-5% CaF2 . Experi-mental results show that the melting point of the optimized slag declines, and there are apparent decreases in the number, area and mean diameter of inclusions in the steel.