Investigation of Segregation Behavior in the Riser/Castings Junction of Heavy-section Steel Castings

대형주강 압탕부의 편석거동 고찰

  • Kim, Ji-Tae (Department of Materials Processing Engineering, Graduate School, Pukyung National University) ;
  • Park, Heung-Il (Department of Materials Processing Engineering, Graduate School, Pukyung National University) ;
  • Kim, Woo-Yeol (Department of Materials Processing Engineering, Graduate School, Pukyung National University) ;
  • Lee, Byung-Woo (Department of Materials Processing Engineering, Graduate School, Pukyung National University)
  • 김지태 (부경대학교 대학원 소재프로세스공학과) ;
  • 박흥일 (부경대학교 대학원 소재프로세스공학과) ;
  • 김우열 (부경대학교 대학원 소재프로세스공학과) ;
  • 이병우 (부경대학교 대학원 소재프로세스공학과)
  • Received : 2010.06.26
  • Accepted : 2010.08.01
  • Published : 2010.08.30

Abstract

Sulfide segregation behavior, characteristics of solidification microstructure and compositional distribution in the riser/castings junction of heavy-section main bearing support (MBS) steel castings were investigated; Sulfide streaks of A segregation were formed in the transitional region from columnar grain to coarse equiaxed grain and floated with aggregation of the dendritic free crystal. Solute segregation behaviors of elements Si, P and S were V shape negative segregation from the bottom of the castings to upper part of the riser with the reference of vertical center-line of the specimen block. Those of elements C and Mn were V shape negative segregation in the main body and A shape positive segregation in the riser of the casting. Just beneath the pipe shrinkage in the riser segregation ratio of each element was the highest, and that of S was 3.6 times higher, C 3.3 times, P 2.1 times, Si 1.6 times and Mn 1.0 times respectively. [Mn/S] ratio of the specimen block was distributed in the wide range of 20~275.

Keywords

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