摘要
以断面为425 mm×320 mm的42CrMo矩形坯为对象,研究不同的电磁搅拌工艺对连铸坯中心碳偏析以及低倍组织的影响。通过使用Procast软件进行数值模拟,分析了碳偏析的形成机理。结果表明:同时使用结晶器电磁搅拌和末端电磁搅拌或末端电磁搅拌上移1. 5 m,等轴晶率是未使用电磁搅拌的2. 46倍,而且能够改善铸坯CET区域正偏析和中心区域负偏析;只使用末端电磁搅拌等轴晶率是未使电磁搅拌的1. 27倍;施加末端电磁搅拌甚至会加剧中心区域负偏析程度;末端电磁搅拌的参数和位置对中心区域负偏析有影响。
According to 425 mm × 320 mm section of 42 CrMo rectangular billet,the influence of different electromagnetic stirring processes on the carbon segregation and the macrostructure of continuous casting billet was studied. And the formation mechanism of carbon segregation was analyzed by using Procast software. The results showed that,when using mold electromagnetic stirring and end electromagnetic stirring or end electromagnetic stirring moving up a distance at the same time,the equiaxial crystal rate was 2. 46 times than that without using electromagnetic stirring,and segregation in casting CET area and negative segregation in central area could be improved. Only using end electromagnetic stirring the equiaxial crystal rate was 1. 27 times than that of without using electromagnetic stirring. The negative segregation in central region might even increase when end electromagnetic stirring was applied. And the parameters and position of the end electromagnetic stirring had influence on the negative segregation in the central region.
引文
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