电磁搅拌对马氏体不锈钢凝固组织的影响

Effects of Electromagnetic Stirring on Solidified Microstructure of Martensite Stainless Steel

通过马氏体不锈钢的静态浇铸试验研究了电磁搅拌对马氏体不锈钢铸坯凝固组织的影响。使用XRD分析确定马氏体不锈钢中主要相为α-Fe、M、Cr23C6。试验结果表明:电磁搅拌可以大幅提高铸坯的等轴晶率,消除缩孔、缩松,改善铸坯质量,随着搅拌电流的增加,铸坯的等轴晶比率随之增加。施加电磁搅拌后,铸坯晶粒得到细化,铸坯中C、Cr元素的分布变得均匀,屈氏体组织形态和分布发生明显变化:屈氏体组织变小变薄,在基体中的分布也呈弥散化。

Through static casting experiment, the effect of electromagnetic stirring （EMS） on the solidified microstructure of martensite stainless steel billets was investigated. By means of XRD, it was identified that the main phases of the solidified microstructure were α-Fe, M and Cr23C6.The results of the experiment show that the EMS can obviously improve the ratio of equiaxed grains in the martensite stainless steel billets, eliminate the shrinkage and dispersed shrinkage, therefore improve the quality of the billets. The ratio of equiaxed grains increases with the increasing of stirring current. And also with the EMS, the grains of the martensite stainless steel billets become finer; the carbon and the chromium in the billets are better distributed; consequently the appearance and distribution of the troostite in the billets changed obviously： the troostite becomes smaller and thinner, and it distributes in the matrix dispersedly.