Superplstic Forming Analysis of Duplex Stainless Steel with Finite Element Method

유한요소법에 의한 Duplex 스테인레스 강의 초소성 해석

  • Published : 2009.10.01

Abstract

In recent years, there has been a considerable interest in the application of super plastic forming in the aircraft and automotive industries. This requires a detailed design of the technological process in order to exploit its peculiar potentialities better. Nowadays, the finite element method is used to plan the sheet metal forming processes whose simulation requires determination of material constants for super plastic materials. The present work is aimed to show a simple method to characterize super plastic materials duplex stainless steel which was formed by a constant gaspressure to hemispheres with and without back pressure. The forming operation was performed using an in-house designed and built biaxial forming apparatus. The temporal change of dome heights of hemispheres were measured for applying the pressures. The flow stresses and strain rates developed at the top of the dome during the forming step were shown to follow closely the flow stress - strain rate relationship obtained from the strain rate change tests performed at the same temperature.

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References

  1. Hong, S. S., Kim, M. H. and Kim, Y. H., "Analysis of Superplastic Forming Processes Using Finite Element Method," Transactions of the Korean Society of Mechanical Engineers, Vol. 19, No. 6, pp. 1411-1421, 1995
  2. Huh, H., Lee, K. S. and Choi, Y. J., "Finite Element Analysis of Punch Forming of Superplastic Materials," Transactions of the Korean Society of Mechanical Engineers(B), Vol. 20, No. 2, pp. 440-449, 1996
  3. Lee, S.-H., Hong, S.-S. and Lee, J.-S., "Superplasticity and Superplastic Forming," J. of the Korean Society of Mechanical Engineers, Vol. 33, No. 7, pp. 628-635, 1993
  4. Hwang, K.-C., Kwon, J.-W. and Yoon, J.-H., "Creep Behaviours of Duplex Stainless Steel," Transactions of the Korean Society of Machine Tool Engineering, Vol. 14, No. 2, pp. 42-47, 2005
  5. Senthil Kumar, V. S., Viswanathan, D. and Natarajan, S., "Theoretical prediction and FEM analysis of superplastic forming of AA7475 aluminum alloy in a hemispherical die," Journal of Materials Processing Technology, Vol. 173, No. 3, pp. 247-251, 2006 https://doi.org/10.1016/j.jmatprotec.2005.04.112
  6. ABAQUS, "ABAQUS Example Problems Manual," ABAQUS, 2006
  7. Budiansky, B., "A reassessment of deformation theories of plasticity," J. Appl. Mech., Vol. 26, No. 2, pp. 259-264, 1959