The Effect of the Heating Conditions on the Warm Hydro-Formability of the Alumium Alloys

알루미늄합금의 열간 액압성형법 성형성에 대한 가열조건의 영향도 분석

  • Kim, Bong-Joon (Dept. of Mechanical & Precision Eng., Pusan National University) ;
  • Park, Kwang-Su (Dept. of Mechanical & Precision Eng., Pusan National University) ;
  • Ryu, Jong-Soo (Dept. of Mechanical & Precision Eng., Pusan National University) ;
  • Son, Sung-Man (Dept. of Mechanical & Precision Eng., Pusan National University) ;
  • Moon, Young-Hoon (Dept. of Mechanical & Precision Eng., Pusan National University)
  • 김봉준 (부산대학교 정밀기계공학과) ;
  • 박광수 (부산대학교 정밀기계공학과) ;
  • 류종수 (부산대학교 정밀기계공학과) ;
  • 손성만 (부산대학교 정밀기계공학과) ;
  • 문영훈 (부산대학교 정밀기계공학과)
  • Received : 2005.04.25
  • Accepted : 2005.05.24
  • Published : 2005.05.30

Abstract

Modern automobiles are built with a steadily increasing variety of materials and semifinished products. The traditional composition of steel sheet and cast iron is being replaced with other materials such as aluminum and magnesium. But low formability of these materials has prevented the application of the automotive components. The formability can be enhanced by conducting the warm hydroforming using induction heating device which can raise the temperature of the specimen very quickly. The specimen applied to the test is A6061, A7075 extruded tubes which belong to the age-hardenable aluminum alloys. But in the case of A6061 age hardening occurs at room temperature or at elevated temperatures before and after the forming process. In this study the effects of the heating condition such as heating time, preset temperature, holding time during die closing and forming time on the hydroformability are analyzed to evaluate the phenomena such as dynamic strain hardening and ageing hardening at high temperatures after the hydroforming process.

Keywords

References

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