北京科技大学学报
北京科技大學學報
북경과기대학학보
JOURNAL OF UNIVERSITY OF SCIENCE AND TECHNOLOGY BEIJING
2015年
1期
20-29
,共10页
孙彦辉%赵勇%蔡开科%孙赛阳%马志飞%方忠强
孫彥輝%趙勇%蔡開科%孫賽暘%馬誌飛%方忠彊
손언휘%조용%채개과%손새양%마지비%방충강
炼钢%硅钢%夹杂物%尖晶石%钙处理%变性
煉鋼%硅鋼%夾雜物%尖晶石%鈣處理%變性
련강%규강%협잡물%첨정석%개처리%변성
steelmaking%silicon steel%inclusions%spinels%calcium treatment%modification
对无取向硅钢钙处理过程中镁铝尖晶石夹杂的变性机理进行了研究,重点考察了钙处理前期和中期MgO-Al2 O3的变性过程.钙处理前,钢中除了发现单纯的MgO- Al2 O3外,还发现少量被AlN包裹的MgO- Al2 O3.钙处理1.5 min后,在MgO-Al2 O3表面有中间产物CaS或CaO形成;钙处理4.5 min后,生成由内到外依次为MgO-Al2 O3、CaO-MgO-Al2 O3和CaO-Al2 O3的夹杂物;钙处理10 min后,未反应的MgO-Al2 O3消失,CaO-MgO-Al2 O3和CaO-Al2 O3的成分趋于均匀.通过热力学计算得到了Al2 O3/MgO-Al2 O3/MgO和MgO-Al2 O3/xCaO·yAl2 O3的稳定相图,发现在含铝越高的钢中,镁铝尖晶石变性越困难.结合夹杂物的扫描电镜观察、能谱分析和面扫描图分析结果,提出了夹杂物的变性路径:MgO或Al2 O3→MgO- Al2 O3→CaO-MgO-Al2 O3→CaO-Al2 O3;在产物的中间层CaO-MgO-Al2 O3中,Al2 O3含量除了一般情况下的逐渐降低外,偶尔还存在突然升高的情况.
對無取嚮硅鋼鈣處理過程中鎂鋁尖晶石夾雜的變性機理進行瞭研究,重點攷察瞭鈣處理前期和中期MgO-Al2 O3的變性過程.鈣處理前,鋼中除瞭髮現單純的MgO- Al2 O3外,還髮現少量被AlN包裹的MgO- Al2 O3.鈣處理1.5 min後,在MgO-Al2 O3錶麵有中間產物CaS或CaO形成;鈣處理4.5 min後,生成由內到外依次為MgO-Al2 O3、CaO-MgO-Al2 O3和CaO-Al2 O3的夾雜物;鈣處理10 min後,未反應的MgO-Al2 O3消失,CaO-MgO-Al2 O3和CaO-Al2 O3的成分趨于均勻.通過熱力學計算得到瞭Al2 O3/MgO-Al2 O3/MgO和MgO-Al2 O3/xCaO·yAl2 O3的穩定相圖,髮現在含鋁越高的鋼中,鎂鋁尖晶石變性越睏難.結閤夾雜物的掃描電鏡觀察、能譜分析和麵掃描圖分析結果,提齣瞭夾雜物的變性路徑:MgO或Al2 O3→MgO- Al2 O3→CaO-MgO-Al2 O3→CaO-Al2 O3;在產物的中間層CaO-MgO-Al2 O3中,Al2 O3含量除瞭一般情況下的逐漸降低外,偶爾還存在突然升高的情況.
대무취향규강개처리과정중미려첨정석협잡적변성궤리진행료연구,중점고찰료개처리전기화중기MgO-Al2 O3적변성과정.개처리전,강중제료발현단순적MgO- Al2 O3외,환발현소량피AlN포과적MgO- Al2 O3.개처리1.5 min후,재MgO-Al2 O3표면유중간산물CaS혹CaO형성;개처리4.5 min후,생성유내도외의차위MgO-Al2 O3、CaO-MgO-Al2 O3화CaO-Al2 O3적협잡물;개처리10 min후,미반응적MgO-Al2 O3소실,CaO-MgO-Al2 O3화CaO-Al2 O3적성분추우균균.통과열역학계산득도료Al2 O3/MgO-Al2 O3/MgO화MgO-Al2 O3/xCaO·yAl2 O3적은정상도,발현재함려월고적강중,미려첨정석변성월곤난.결합협잡물적소묘전경관찰、능보분석화면소묘도분석결과,제출료협잡물적변성로경:MgO혹Al2 O3→MgO- Al2 O3→CaO-MgO-Al2 O3→CaO-Al2 O3;재산물적중간층CaO-MgO-Al2 O3중,Al2 O3함량제료일반정황하적축점강저외,우이환존재돌연승고적정황.
The evolution mechanisms of MgO-Al2 O3 in the process of calcium treatment in non-oriented silicon steel were studied by laboratory experiments, with focus on the evolution process in the early and middle of calcium treatment. A small amount of MgO-Al2 O3 surrounded by AlN was occasionally detected besides many pure spinels before calcium treatment. CaS or CaO formed as a tran-sient inclusion in the MgO-Al2 O3 surface 1. 5 min after calcium treatment. The composition from the inner part to outer part of inclu-sions was MgO-Al2 O3 , CaO-MgO-Al2 O3 and CaO-Al2 O3 in order 4. 5 min after calcium treatment. 10 min after calcium treatment, unreacted MgO-Al2 O3 spinels disappeared, and simultaneously CaO-MgO-Al2 O3 and CaO-Al2 O3 inclusions became homogeneous in composition. The phase stability diagrams of Al2 O3/MgO-Al2 O3/MgO and MgO-Al2 O3/xCaO·yAl2 O3 were calculated using thermo-dynamic data. The result showed that it was difficult to modify MgO-Al2 O3 spinels with very high aluminum content. In combination with the scanning electron microscopy images, energy-dispersive spectra and element mappings of typical inclusions, the evolution route of an inclusion was described as MgO or Al2 O3→MgO-Al2 O3→CaO-MgO-Al2 O3→CaO-Al2 O3 , and the alumina content occa-sionally showed a sudden increase besides a common decrease in the middle part of the product.