Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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The Effect of Pressure on Liquid Segregation in Direct Rheo-Forging Process of Aluminum Alloys

알루미늄 소재의 레오로지 직접단조공정에서 가압력이 액상 편석에 미치는 영향

  • 오세웅 (부산대학교 정밀기계공학과) ;
  • 배정운 (부산대학교 정밀기계공학과) ;
  • 강충길 (부산대학교 정밀기계공학부)
  • Published : 2007.06.01
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Abstract

Rheo-forging process of aluminum alloy is suitable for large parts of net shape without defects and excellent mechanical properties in comparison with conventional die casting and forging process. To control the microstructure of the product with high mechanical properties in rheo-forming, solid fraction is required to prevent porosity and liquid segregation. Therefore, in rheo-forging process, die shape, pressure type and solid fraction are very important parameters. The defects such as porosity, liquid segregation and unfitting phenomena occur during rheo-forging process. To prevent these defects, mechanical properties and microstructure analysis of samples versus the change of pressure are carried out and the problem and its solutions are proposed. Also, the mechanical properties versus various pressures were compared with and without heat treatment. The alloys used for rheo-forming are A356 and 2024 aluminum alloy. The rheology material is fabricated by electromagnetic process with controlling current and stirring time.

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References

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