二冷辊式电磁搅拌对高强钢低倍组织与性能的影响

通过工业化试验数据,系统地研究了二冷辊式电磁搅拌对高强钢内部质量及轧材性能的影响。结果表明:二冷辊式电磁搅拌能有效地改善连铸坯的低倍组织,低倍评级从1.5~3.0级提高至1.0~1.5级,中间裂纹都提高至0.5级以下,中心偏析从连续、半连续的A、B类偏析改善成点状的C类偏析;在目前工况下,当电流为400 A、频率为7 Hz时,铸坯的低倍质量最佳。使用辊式电磁搅拌后,元素C、P的成分偏析增加,尤其在铸坯1/4厚度处,C、P呈明显的负偏析,即白亮带区域。电磁搅拌对轧材的基本性能无明显影响,且能明显减轻轧材的中心偏析或中心区带状组织。

Effect of roller EMS on macrostructure and properties of high strength steel

The effects of roller electromagnetic stirring （roller EMS） on the internal quality and properties of high-strength steel were systematically studied through industrial trial. The result shows that roller EMS can effectively improve the macrostructure of slab. The macrostructure rating is improved from 1.5-3.0 to 1.0-1.5, the intermediate cracks are increased to below 0.5. And the semi-continuous A or B-type segregation improves to point-like C-type segregation. Under the current working conditions, when the current is 400 A and the frequency is 7 HZ, the slab macrostructure is the best. When using roller EMS, the segregation of elements C and P increases. Especially at the thickness of 1/4 of the slab, C and P show a significant negative segregation, which is called “white band” region. Electromagnetic stirring has no significant effect on the basic properties of high-strength steel, and can significantly reduce the central segregation or the banded structure in the central zone.