Influence of rare earth metals on macrostructure of continuously cast steel rolling pipe

The influence of rare earth metals (next it's called RE) on macrostructure of continuously cast steel ingot have been studied in the full-scale industrial trials. The results can be described as follow: RE addition macrosegregation, enlargement of equiaxed zone and reduced loose structure. The centerline ingot seggregation was expanded. The length of seggregation line was distributed. RE sulphides were mainly precipitated in dendrite arms. These results were compared with CaSi treatment.