Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/191415

Title

Earing predictions based on asymmetric nonquadratic yield function

Author(s)

Yoon, J. W.;  Barlat, F.;  Chung, K.;  Pourboghrat, F.;  Yang, D. Y.

Abstract

A nonquadratic yield function (Yld96) which simultaneously accounts for the anisotropy of uniaxial yield stresses and r values was newly implemented in a finite element code. Yield surface shapes, yield stress and r-value directionalities of Yld96 were investigated and compared with those of the previous yield function, Yld91. Complete formulations for Yld96 implementation and the calculation of coefficients were also discussed for the convenient use of Yld96. A 2090-T3 aluminum alloy sheet sample was modeled and earing formation during a cup drawing test was simulated using the FEM code. The results of earing and thickness strain profiles were compared with the results obtained with Yld91. Investigations were further carried out with a translated yield surface to account for the strength differential effect observed in this material. Computation results with the translated yield surface were in very good agreement with experimental results. It was shown that the yield surface shape and translation have a significant influence on the prediction of the cup height profile during the drawing of a circular blank.

Publication type

Journal article

Source

International Journal of Plasticity, Vol. 16, no. 9 (Aug 2000), pp. 1075-1104

Publication year

2000

FOR Code(s)

0905 Civil Engineering;  0912 Materials Engineering;  0913 Mechanical Engineering

Keyword(s)

Earing;  FEM;  Finite element method;  Planar anistropy;  Strength differential effect;  Sheet forming;  Yield function

Publisher

Pergamon

ISSN

0749-6419

Publisher URL

http://dx.doi.org/10.1016/s0749-6419(99)00086-8

Copyright

Copyright © 2000 Elsevier Science Ltd. All rights reserved.

Peer reviewed