Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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RRA Treatment of Semi-Solid Al-Zn-Mg-Cu Al Alloy Fabricated by Cooling Plate

냉각판으로 제조된 Al-Zn-Mg-Cu계 반응고 알루미늄 합금의 RRA 처리

  • Kim, Dae-Hwan (i-Cube Center, Engineering Research Institute, Gyeongsang National University) ;
  • Shim, Sung-Yong (i-Cube Center, Engineering Research Institute, Gyeongsang National University) ;
  • Kim, Young-Hwa (i-Cube Center, Engineering Research Institute, Gyeongsang National University) ;
  • Lim, Su-Gun (i-Cube Center, Engineering Research Institute, Gyeongsang National University)
  • 김대환 (i-Cube Center, 공학연구원, 경상대학교) ;
  • 심성용 (i-Cube Center, 공학연구원, 경상대학교) ;
  • 김영화 (i-Cube Center, 공학연구원, 경상대학교) ;
  • 임수근 (i-Cube Center, 공학연구원, 경상대학교)
  • Published : 2009.12.31
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Abstract

The optimum RRA heat treating conditions and SCC (stress corrosion cracking) resistance of semi-solid Al-Zn-Mg-Cu alloy fabricated by inclined cooling plate were compared with those of conventional mould cast alloys. The non-stirring method characterized by using a cooling plate can effectively eliminate dendritic structure and form a fine globular semisolid microstructure in as-cast Al-Zn-Mg-Cu alloy and the SCC resistance of semi-solid Al-Zn-Mg-Cu alloy was higher than that of conventional mold cast alloy. Also, after retrogressed treatment at RRA heat treatment of semi-solid Al-Zn-Mg-Cu alloy, retrogressed treatment time has increased more than 10 minutes at $180^{\circ}C$ to recovery the T6 heat treatment strength.

Keywords

References

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