Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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Morphology and Segregation of Sulfide Inclusions in Cast Steels (I) (A Fabrication of Fe-FeS Alloys and the Observation of Their Sulfide Morphology)

주강의 유화물 형태와 편석에 대한 연구 (I) (Fe-FeS 합금의 제조와 유화물 형태 관찰)

  • Park, Heung-Il (Department of materials processing engineering, Graduate school, Pukyung National University) ;
  • Kim, Ji-Tae (Samyoung M-Tek Co., Ltd.) ;
  • Kim, Sung-Gyoo (Department of materials processing engineering, Graduate school, Pukyung National University)
  • 박흥일 (부경대학교 대학원 소재프로세스공학과) ;
  • 김지태 (삼영엠텍(주)) ;
  • 김성규 (부경대학교 대학원 소재프로세스공학과)
  • Published : 2009.10.31
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Abstract

In order to investigate the microstructural morphology of the sulfide expected from the Fe-FeS phase diagram, a vacuum-sealed quartz tube where pure iron (99.9%) and sulfur (99.99%) powders were charged was heated upto $1000^{\circ}C$ in the electric resistance furnace, held for 96 hours and quenched in cold water and then, rod specimen was produced. Compositional difference of the sulfur between upper and lower parts of the rod was 7.5wt.% and segregation of the sulfur was gradually increased from the lower part to the upper one of the rod. The rod specimen was divided into three parts by the microstructural morphology of the sulfide. The upper part of the rod specimen revealed single phase FeS intermetallic. In the middle part of the specimen, hyper-eutectic microstructure where primary FeS was precipitated first and then, eutectic of $\alpha$-Fe and FeS was formed in the inter-dendritic region of the FeS. Especially, hypo-eutectic microstructure was appeared in the lower part of the specimen. After primary dendrite of $\alpha$-Fe solidified, FeS dendrite which included small amount of $\alpha$-Fe and FeS eutectic in the inter-dendritic region was formed.

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References

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