대한금속재료학회지 (Korean Journal of Metals and Materials)

  • 제49권2호
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  • Pages.104-111
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  • 2011
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  • 1738-8228(pISSN)
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  • 2288-8241(eISSN)
대한금속재료학회 (The Korean Institute of Metals and Materials)
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강소성압연법으로 제조된 초미세립 마그네슘 재료의 마이크로 성형능

Micro-forming Ability of Ultrafine-Grained Magnesium Alloy Prepared by High-ratio Differential Speed Rolling

  • 유성진 (홍익대학교 신소재공학과) ;
  • 김우진 (홍익대학교 신소재공학과)
  • Yoo, Seong Jin (Department of Materials Science and Engineering, Hongik University) ;
  • Kim, Woo Jin (Department of Materials Science and Engineering, Hongik University)
  • 투고 : 2010.06.03
  • 발행 : 2011.02.25
⟨ 이전 논문 다음 논문 ⟩

초록

An ultrafine grained Mg-9Al-1Zn magnesium alloy with the mean grain size less than $1{\mu}m$ was produced by using high-ratio differential speed rolling. The processed alloy exhibited excellent superplasticity at relatively low temperatures. The micro-forming tests were carried out using a micro-forging apparatus with micro V-grooved shaped dies made of silicon and the micro-formability was evaluated by means of micro-formability index, $R_f$ ($=A_f/A_g$, $A_f$: formed and inflowed area into the V-groove, $A_g$: area of the V-groove). The $R_f$ value increased with temperature up to $280^{\circ}C$ and then decreased beyond $300^{\circ}C$. The decrease of the $R_f$ value at $300^{\circ}C$ was attributed to the accelerated grain coarsening. Increasing the micro-forging pressure increased the $R_f$ values. At a given die geometry, die filling ability decreased as the die position moved away from the die center to the end. FEM simulation predicted this behavior and a method of improving this problem was proposed.

키워드

과제정보

연구 과제번호 : 난성형성 경량합금 판재 정밀성형 기술

연구 과제 주관 기관 : 지식경제부

참고문헌

  1. M. Geiger, M. Kleiner, R. Eckstein, N. Tiesler, and U. Engel, CIRP Annals-Manufacturing Tech. 50, 455 (2001).
  2. U. Engel and R Eckstein, J. Mater. Proce. Tech. 125, 35 (2002).
  3. Y. Saotome, K. Imai, and N. Sawanobori, J. Mater. Proce. Tech. 140, 379 (2003). https://doi.org/10.1016/S0924-0136(03)00828-8
  4. Y. Saotome, Y. Noguchi, T. Zhang, and Akihisa Inoue, Mater. Sci. Eng. A 375, 389 (2004).
  5. Y. Sotome, T. Hatori, T. Zhang, and A. Inoue, Mater. Sci. Eng. A 304, 716 (2001).
  6. Y. Saotome, K. Itoh, T. Zhang, and A. Inoue, Scripta Mater. 44, 1541 (2001). https://doi.org/10.1016/S1359-6462(01)00837-5
  7. Y. Saotome, S. Miwa, T. Zhang, and A. Inoue, J. Mater. Proce. Tech. 113, 64 (2001). https://doi.org/10.1016/S0924-0136(01)00605-7
  8. V. M. Segal et al., Russian Metall 1, 99 (1981).
  9. M. Furukawa, Z. Horita, M. Nemoto, R. Z. Valeiv, and T. G. Langdon, Mater. Characterization 37, 277 (1996). https://doi.org/10.1016/S1044-5803(96)00131-3
  10. W. J. Kim, J. B. Lee, W. Y. Kim, H. T. Jeong, and H. G. Jeong, Scripta Mater. 56, 309 (2007). https://doi.org/10.1016/j.scriptamat.2006.09.034
  11. W. J. Kim, J. D. Park, and W. Y. Kim, J. Alloys and Compounds 460, 289 (2008). https://doi.org/10.1016/j.jallcom.2007.06.050
  12. H. J. Frost and M. F. Ashby, Deformation-Mechanism Maps, Pergamon Press, Oxford (1982).
  13. W. J. Kim, J. D. Park, J. Y. Wang, and W. S. Yoon, Scripta Mater. 57, 755 (2007). https://doi.org/10.1016/j.scriptamat.2007.06.020
  14. W. J. Kim, S. J. Yoo, and H. K. Kim, Scripta Mater. 59, 599 (2008). https://doi.org/10.1016/j.scriptamat.2008.05.014