Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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Analytical Study of the Effect of Material Properties on the Formability of Sheet Metals based on the M-K Model

M-K 모델 기반의 박판금속 성형성 평가에서 물성의 영향에 대한 해석적 연구

  • ;
  • 김석봉 (KAIST 기계항공시스템학부) ;
  • 허훈 (KAIST 기계항공시스템학부)
  • Received : 2010.08.10
  • Accepted : 2010.10.25
  • Published : 2010.11.01
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Abstract

This paper investigates the effect of material properties on the formability of sheet metals based on the Marciniak-Kuczynski model (M-K model). The hardening behavior of the material is modeled as the Hollomon model with the strain rate effect. The yield surfaces are constructed with Hosford79 yield function. The material properties considered in this study include the R-value, the strain hardening exponent, the strain rate hardening exponent, and the crystal structure of the material. The effect of the crystal structure on formability is roughly expressed as the change of the yield surface by varying the value of the exponent in Hosford79 yield function. Results show that the R-value affects neither the magnitude nor the shape of right hand side of forming limit diagrams (FLDs). Higher strain hardening exponent and higher strain rate hardening exponent improve the formability of sheet metals because they stabilize the forming processes.

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References

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