Abstract:The 2205 duplex stainless steel continuous casting billets of two advanced stainless steel production enterprises at home and abroad were taken as the research object, and the corresponding solidification structure characteristics and carbon macrosegregation distribution were compared and analyzed. The study found that the columnar crystals in the solidified structure of 2205 continuous casting slabs abroad were more developed, the proportion of columnar crystals was 76%, and the overall carbon macrosegregation was low. The equiaxed crystals of domestic 2205 continuous casting billet accounted for the main part. The proportion of equiaxed crystals was 58%, and there was serious central carbon segregation. Furthermore, the density of the columnar crystal area and the equiaxed crystal area of the foreign samples was compared. The average density of the columnar crystal area was 0.89, which was higher than 0.84 of the equiaxed crystals. Therefore, in order to obtain a more uniform composition of the continuous casting slab and a lower degree of macrosegregation, a reasonable ratio of columnar crystals to equiaxed crystals was very important.
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