한국주조공학회지 (Journal of Korea Foundry Society)

  • 제25권6호
  • /
  • Pages.240-248
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  • 2005
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  • 1598-706X(pISSN)
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  • 2288-8381(eISSN)
한국주조공학회 (Korea Foundry Society)
권호 표지

반고상 A356 합금 슬러리의 미세조직에 따른 유동특성에 관한 연구

Effects of Microstructure Morphology on Fluid Flow Characteristics of A356 Commercial Alloy in Semi-Solid Slurry

  • 김재민 (연세대학교 금속시스템공학과 재료공정 모델링 연구실) ;
  • 이승훈 (연세대학교 금속시스템공학과 재료공정 모델링 연구실) ;
  • 홍준표 (연세대학교 금속시스템공학과 재료공정 모델링 연구실)
  • Kim, Jae-Min (Center for Computer-Aided Solidification Processing(CASP), Dept. of Metallurgical Engineering, Yonsei University) ;
  • Lee, Seung-Hoon (Center for Computer-Aided Solidification Processing(CASP), Dept. of Metallurgical Engineering, Yonsei University) ;
  • Hong, C.P. (Center for Computer-Aided Solidification Processing(CASP), Dept. of Metallurgical Engineering, Yonsei University)
  • 발행 : 2005.12.20
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초록

The rheocasting characteristics are strongly influenced by the microstructural morphology such as particle size, form factor and contiguity. In this study, the effect of structural morphology on fluid flow characteristics of A356 semi-solid alloy was investigated with a vacuum suction fluidity test. Semi-solid metal slurry was made by the mechanical stirring, the liquidus casting, and H-NCM to be analysed. H-NCM could obtain uniform and fine globular microstructures of 0.9 form factor and 55 ${\mu}m$ particle size. Inoculation was found to be effective for reducing particle size, however, for H-NCM it should be avoided due to the cause of increasing contiguity. The fluidity test indicated that the non-stirring method had higher fluidity and smaller liquid segregation in the same solid faction of 0.4 than the stirring method, for smaller particle size and higher form factor. It was observed that liquid segregation decreased as the particle size is smaller and form factor is higher. The results of die-casting experiment were a good agreement with those of fluidity test.

키워드

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