本文根据常规凝固(结晶无方向性)与单向凝固的实验结果证明了稀土对优化钢的结晶组织有良好的作用。不过在不同含硫水平的原钢中影响的主要方面有所差别。高硫条件下,稀土细化晶粒及一次枝晶提高等轴晶率作用明显,但对二次枝晶影响不大;低硫条件下,主要是细化了二次枝晶。 According to the experimental results of conventional solidification (non-directional crystallization) and unidirectional solidification, the results show that rare earth has a good effect on the crystallization of the optimized steel. However, there are differences in the main aspects affected in the raw steel at different sulfur levels. Under high sulfur conditions, the grain refinement of rare earth and the primary dendrites have obvious effect on increasing the equiaxed grain rate, but have little effect on the secondary dendrites. Under low sulfur conditions, the secondary dendrites are mainly refined.