V偏析生成機構の理論解析と模型実験

抄録

Investigation on V-type segregation is now a crucial subject not only in the production of large size ingots but also in the process of continuous casting with electromagnetic stirring.
To clarify the formation mechanism of V-type segregation, marked V-type segregations are made in the cold model experiment by use of NH₄Cl aqueous solution. The formation mechanism of V-type segregation is considered to consist of the following two processes, namely (1) the formation process of fissures caused by slipping phenomena of equiaxed crystals and (2) the growing process from fissures to V-type segregations. The former induces the V-type slip lines in equiaxed zone and the latter makes V-type channel segregation.
The slipping phenomena in equiaxed zone are theoretically analyzed on the basis of powder mechanics and the calculated shapes of slip lines are compared with the shapes of V-type segregation observed in the cold model experiments.