Formability Evaluation Using Modified Cockcroft Criterion with Strain Paths for Sheet Metal Forming

Abstract:

In most situations, original Cockcroft criterion underestimates material formability in the first quadrant of FLD. So far, some modified Cockcroft criteria have been reported for different applications. This presentation will focus on the modified Cockcroft criterion which takes strain-path effect into consideration. This paper demonstrates the accuracy of this criterion through limiting dome height test, free bulge test, and the biaxial tensile test using cruciform specimen respectively. The results showed that the modified Cockcroft criterion with strain path effect has good agreement with experimental results.

• Periodical: Key Engineering Materials (Volume 626)
• Pages: 495-501
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.626.495
• Online since: August 2014
• Authors: Rong Shean Lee*, Ta Wei Chien
• Keywords: Forming Limit Diagram (FLD), Modified Cockcroft Criterion, Strain Path

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