Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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A Study on the Compressive Properties of Thixo-Extruded 7075 Aluminum Alloy

7075 알루미늄 합금 반용융 압출재의 압축특성

  • 김대환 (경상대학교 항공기부품기술연구소) ;
  • 정현주 (경남테크노파크 지능기계.소재센터) ;
  • 임수근 (경상대학교 항공기부품기술연구소)
  • Received : 2017.02.13
  • Accepted : 2017.04.22
  • Published : 2017.04.30
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Abstract

Given that the conventional extrusion of high-strength Al alloys such as 7075 aluminum alloys is difficult due to their very low extrudability as compared to that of 6061 aluminum alloys, thixo-extrusion can be used to obtain a high-strength material easily at a lower extrusion pressure as compared to conventional extrusion. In this study, hot- and thixo-extruded 7075 aluminum alloys are prepared by a vertical forward extrusion process and their microstructures, hardness levels, and compressive properties are investigated. Hot-extruded alloy bars are assessed to obtain a microstructure elongated in the extrusion direction, whereas with thixo-extruded alloy bars, it was possible to obtain a microstructure having fine and equiaxed grains by dynamic recrystallization. The resulting isotropy and improved formability at the hot deformation temperature of the thixo-extruded alloy were attributed to the fine and equiaxed grains formed by the thixo-extrusion process.

Keywords

References

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