Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
권호 표지

Effect of the Casting Conditions on the Globulization of Primary Al of $AlSi_7Mg$ Alloy

($AlSi_7Mg$알루미늄 합금의 초정 구형화에 대한 주조조건의 영향

  • Han, Yo-Sub (The Department of Materials, Korea Institue of Science and Technology) ;
  • Lee, Ho-In (The Department of Materials, Korea Institue of Science and Technology) ;
  • Lee, Jae-Chul (The Department of Materials, Korea Institue of Science and Technology)
  • 한요섭 (한국과학기술연구원 재료연구부) ;
  • 이호인 (한국과학기술연구원 재료연구부) ;
  • 이재철 (한국과학기술연구원 재료연구부)
  • Published : 2003.02.20
Download PDF
⟨ Previous Next ⟩

Abstract

Semisolid forming requires alloys with non-dendritic microstructure of the thixotropy. Recently, low pouring temperture method without stirring, i.e. liquidus casting has been found out new fabrication method of the semisolid metals. Effects of melt superheat and mold conditions on the globulization of primary Al of $AlSi_7Mg$ alloy were investigated in gravity casting process without stirring. The microstructures of primary Al as function of melt superheat and mold temperature show globular, rosette and dendritic shapes. The conditions for globular microstructure of primary Al were low melt superheat < 35 K and low mold temperature < 500 K. The thermal conditions for globular microstructure of primary Al were undercooled melt at early solidification stages and slow cooling < 0.6 K/s. It was found that the initial microstructure was maintained throughout the solidification and the globules of primary Al can be obtained by high nucleation of fine and spherical nuclei due to enhanced undercooling of melt.

Keywords

References

  1. Metall. Trans. v.3 Rheological Behavior of Sn-15 Pct Pb in the Crystallization Ranges D. B. Spencer;R. Mehrabian;M. C. Flemings https://doi.org/10.1007/BF02642580
  2. Metall. Trans. v.A22 Behavior of metal alloys in the semisolid state M. C. Flemings
  3. Trans. 18th Int. Die casting Congress & Exposition Metallurgical Aspects of Thixoforming of A356.0 Alloys W. R. Loue;M. Brimint;C. Pluchon;P. Y. Menet;M. Garat
  4. J. Jpn. Inst. Light Met. v.47 R. Shibata;T. Souda;T. Kanauchi https://doi.org/10.2464/jilm.47.651
  5. 4th Decennial Int. Conf. on Solidification Processing T. Motegi;K. Kondou;R. Chi;S. Aotama
  6. Metallurgia Italiana v.85 Thxoforming of Aluminium Alloys Using Modified Chemical Grain Refinement fir Billet production G. Wan;T. Witulski;G. Hirt
  7. 5th Int. Conf. on the Semi-Solid processing of Alloys and Composites Microstructure Evolution of Semi-Solid Al-7Si-0.4Mg Alloy by Short Time Supersonic Vibrations C. Liu;Y. Pan;S. Aoyama
  8. Conference Proceedings of Japan Die Casting Association v.JD98-19 Characteristics of UBE Rheocasting Process M. Adachi
  9. Aluminium v.76Jg. Metallurgical and Processing Aspects of NRC Semi-Solid Casting Technology H. Kaufmann;H. Wabusseg;P. J. Uggowitzer
  10. 5th Int. Conf. on the Semi Solid processing of Alloys and Composites Thxoformability of Aluminium Alloys T. Witulski;U. Morjan;I. Niedick;G. Hirt
  11. Materials Science and Eng. v.A246 Liquidus Casting of a Wrought Aluminum Alloy 2618 fir Thixoforming K. Xia;G. Tausing