Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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Nanocrystallization of Metallic Powders during High Pressure Torsion Processing

금속분말의 고압비틀림 성형시 나노결정화

  • 윤승채 (충남대학교 대학원 나노공학부) ;
  • 곽은정 (충남대학교 대학원 나노공학부) ;
  • 김택수 (한국생산기술연구원) ;
  • 홍순익 (충남대학교 나노공학부) ;
  • 김형섭 (충남대학교 나노공학부)
  • Published : 2007.08.01
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Abstract

Microstructure and microhardness of metallic powders of pure copper were studied after high pressure torsion(HPT) processing with 10 turns of die rotation and high pressure of 6 GPa. The grain size of copper decreases drastically after HPT and reaches nanometer size ranges. During HPT, the hardness of consolidates of copper powders increases with increasing the temperature of HPT processing. Examinations of the fracture surfaces indicated evidence of ductile fracture. The results proved that HPT of copper powders has a beneficial effect for homogeneous deformation with reducing grain size.

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References

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