某钢厂宽厚板250 mm×1820 mm连铸机使用包晶钢类型MB-59型保护渣生产w(C)为0.120%～0.150%钢种时，连铸坯表面出现大量纵向裂纹与皮下裂纹缺陷。通过提高保护渣碱度，降低保护渣黏度，改善铸坯坯壳与结晶器壁之间渣膜传热等技术措施，使铸坯的表面裂纹与皮下裂纹缺陷得到了有效控制。同时，对浇注w(C)为0.090%～0.120%钢种时采用MB-59型保护渣连铸坯表面无裂纹的原因进行了探讨分析，认为由于选分结晶，优先凝固的坯壳中碳质量分数低于钢液原始碳质量分数，使优先凝固的坯壳中w(C)实际已经小于0.090%，不再属于裂纹敏感性强的包晶钢范围，因此表面质量较好。
A lot of longitudinal cracks were observed on the surface of 250 mm × 1 820 mm wide heavy slab containing 0.120%-0.150%carbon,produced using the protecting slag for peritectic steel in one Wide Heavy Plate Plant. These sur-face longitudinal and subsurface cracks have been effectively controlled by improving the basicity of mold powder, de-creasing mold powder viscosity and improving the heat transfer between the mold wall and the slab shell. The reason for the slab with 0.090%-0.120%carbon be free of surface cracks is the segregation crystallization, which causes the carbon content in the initial solidified shell is lower than 0.090%.
参考文献
| [1] | 高仲,张兴中,姚书芳.包晶钢铸坯裂纹形成机理的实验研究[J].钢铁研究学报,2009(10):8-11. |
| [2] | 赵和明,王新华,张炯明.影响高速浇铸亚包晶钢表面质量的因素研究[J].钢铁,2006(06):22-26. |
| [3] | Hiriki S. Influence of mold fluxes on longitudinal surface cracks during high speed continuous casting of steel slabs[C]//steel-making conference proceedings. Chicago:AIME,1994:397.,1994. |
| [4] | 王三忠,王新志,宋素格,刘海强,高新军.宽板坯表面纵裂纹的探索分析[J].钢铁,2010(05):44-48. |
| [5] | 吴坚,许健,杨应东.减少连铸异型坯表面纵裂纹的工艺研究[J].钢铁,2009(10):95-97,102. |
| [6] | Chakraborty S. Reduction of a luminal slivers[C]//Great Lakes No.2 Continuous Caster Steelmaking Conference Proceedings. Chicago:AIME,1994:389.,1994. |
| [7] | Chakraborty S,Hill W. Improving in steel cleanliness[C]//Great Lakes No.2 Continuous Caster Steelmaking Conference Pro-ceedings. Chicago:AIME, 1995:401.,1995. |
| [8] | 姚书芳.天钢连铸板坯表面纵裂产生原因的分析及对策[J].钢铁研究学报,2010(04):24-26. |
| [9] | 孔祥涛,周德,陈宏,张宝全,诸葛铭毅,孙其松.小方坯连铸中碳钢铸坯表面缺陷与保护渣性能选择[J].钢铁,2010(08):99-103. |
| [10] | 朱苗勇.现代冶金学[M].北京:冶金工业出版社,2005.,2005. |
| [11] | 李阳,王京,兰鹏,孙海波,曾智,张家泉.合金元素对钢亚包晶转变与连铸纵裂倾向的影响[J].钢铁,2013(12):73-79. |
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