소성∙가공 (Transactions of Materials Processing)

한국소성∙가공학회 (The Korean Society for Technology of Plasticity and materials processing)
권호 표지
DOI QR코드

DOI QR Code

반용융 Al-Zn-Mg합금의 고온 압출 시 특성 평가

Characteristics on the Hot Extrusion of Semi-Solid Al-Zn-Mg Alloy

  • 조국래 (한국기계연구원부설 재료연구소/소재성형센터) ;
  • 염종택 (한국기계연구원부설 재료연구소/소재성형센터) ;
  • 심성용 (경상대학교 재료공학부, 항공기 부품기술연구센터) ;
  • 임수근 (경상대학교 재료공학부, 항공기 부품기술연구센터) ;
  • 박노광 (한국기계연구원부설 재료연구소/소재성형센터) ;
  • 김정한 (한국기계연구원부설 재료연구소)
  • 발행 : 2007.08.01
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

Semi-solid Al-Zn-Mg alloys were produced by using a cooling plate method in order to investigate the extrudability. Al melt was poured on cooling plate which was adjusted at $60^{\circ}$ with respect to the horizontal plane, and the melt was cooled by water circulation underneath. Obtained Semi-solid feedstock has globular microstructure but also contains considerable amount of gas pore. Due to the pore, tensile elongation of the semi-solid feedstock was very low and it doesn't show yield point phenomenon. Isothermal hot extrusion was carried out using at $400^{\circ}C$ with a ram speed of 1mm/sec and an extrusion ratio of 25:1. The extruded bar show noticeably improved tensile ductility and strength because pore volume fraction decreased from 5% to 0.8% after extrusion. Mechanical properties of the semi-solid extruded bar were compared with that of commercial casting alloy.

키워드

참고문헌

  1. Sang-Yong Lee, Jung-Hwan Lee, Young-Sun Lee, 1997, Thixoforging Technology of Rapidly Soidified AI-High Si Alloy, 대한금속학회회보 Vol. 10, No. 2, pp. 153-163
  2. Proc. of 3rd lnt. Conf. on the Processing of Semi-Solid Alloys and Composites, 1994, Japan
  3. Proc. of 4th lnt. Conf. on the Processing of Semi-Solid Alloys and Composites, 1996, Englad
  4. 임수근, 김권섭, 1999, 경사냉각판에 의한 반응 고금속의 제조, 한국소성가공학회 고액공존금속의 성형기술 심포지엄(III), pp. 117-130
  5. 김권섭, 임수근, 1999, 경사냉각판으로 제조된 반응고 금속의 미세조직, 한국소성가공학회 고액공존금속의 성형기술 심포지엄(III), pp. 157-172
  6. T. Sheppard, P. J. Tunnic1iffe, S. J. Patterson, 1982, Direct and indirect extrusion of a high strength aerospace alloy(AA7075). J. Mech. Work. Tech. 6, pp. 313-331 https://doi.org/10.1016/0378-3804(82)90031-6
  7. 이상용, 이정환, 이영선, 전재일, 신평우, 1998, A17075 합금의 열간단조와 반응고 단조에 있어서 조직, 성형성 및 경도 특성 비교, 한국소성가공학회지, pp. 620-630