Effect of Process Conditions on the Microstructure and Mechanical Properties of 7175Al Ring Roll Forgings

7175Al 링롤단조재의 미세조직과 기계적 성질에 미치는 공정조건의 영향

  • Lee, I.G. (School of Advanced Materials Engineering & RCAMD, Chonbuk National University) ;
  • Kang, R.K. (School of Advanced Materials Engineering & RCAMD, Chonbuk National University) ;
  • Lee, O.Y. (School of Advanced Materials Engineering & RCAMD, Chonbuk National University)
  • 이인기 (전북대학교 신소재공학부, 신소재개발연구센터) ;
  • 강락경 (전북대학교 신소재공학부, 신소재개발연구센터) ;
  • 이오연 (전북대학교 신소재공학부, 신소재개발연구센터)
  • Received : 2003.10.24
  • Published : 2004.01.30

Abstract

The aim of this study is to investigate the process conditions on the microstructual changes and mechanical properties of large 7175 aluminum ring roll forgings. The billets range from 370 mm to 720 mm in diameter were homogenized and ring roll forged after direct chill casting. The tensile properties of ring roll forged specimen manufactured with ${\Phi}370mm$ billets were superior to those of ${\Phi}720mm$ billets under $T_6$ condition. Also, these properties showed better than those of military specification under $T_{74}$ treatment. The impact value of ring roll forged specimen under $T_{74}$ treatment increased up to 20% than that of $T_6$ condition. The fracture toughness of ring roll forged specimen manufactured with ${\Phi}370mm$ cast billet showed nearly same level of ${\Phi}720mm$ billet which was processed using MF or Cog free forging followed by ring roll forging.

Keywords

References

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