Prediction of Ductile Fracture in Metal Blanking

[+] Author and Article Information
A. M. Goijaerts, L. E. Govaert, F. P. T. Baaijens

Materials Technology, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands

J. Manuf. Sci. Eng 122(3), 476-483 (Oct 01, 1999) (8 pages) doi:10.1115/1.1285909 History: Received April 01, 1999; Revised October 01, 1999
Copyright © 2000 by ASME
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
The blanking process with an indication of the different zones determining the product shape
Grahic Jump Location
Strain hardening behavior
Grahic Jump Location
Experimental results for ductile fracture initiation for varying clearance
Grahic Jump Location
Dimensions of the tensile specimens in mm, thickness is 1 mm
Grahic Jump Location
Minimum thickness of neck after fracture as a function of hydrostatic pressure
Grahic Jump Location
The evaluation of three criteria from literature with one parameter. The critical values C are determined in the 15 percent-experiment; Cockroft & Latham: C=1.40⋅103 [MPa]; Plastic work: C=3.49⋅103 [MPa]; Rice & Tracey, C=2.32[−].
Grahic Jump Location
Results for the adapted Rice & Tracey and Oyane criterion
Grahic Jump Location
Field variable plot of the Oyane integral for an axisymmetric blanking model, at the punch displacement where fracture initiated (15 percent clearance), with two zoomed plots. Maximum value is 2.38. The location of the maximum is in agreement with experimental results.
Grahic Jump Location
Simulation of a tensile test and experimental verification on deformations. In the upper left corner the undeformed tensile specimen is shown with the modelled part(1/8). Upper right, the calculated deformations at fracture initiation are shown with five levels of the equivalent plastic strain. In the center, the three orthogonal views of the deformed specimen are shown with a zoomed plot of the refined mesh in the neck. At the bottom, the experimental fracture surface is compared with the calculated cross-sectional area in the neck at fracture initiation. (Mind the wedge-like shape.)
Grahic Jump Location
The numerical and experimental force displacement curves (left plot). The crosses are the points where the experimental thickness of the neck after fracture is numerically reached for the three different hydrostatic pressures. In the right plot the deformation history of the overall center of the specimen up to the point of fracture initiation (crosses) is presented for the tensile tests under different hydrostatic pressures.
Grahic Jump Location
Validity check in the pressurized tensile tests for the criteria that performed well with a characterization in the blanking process (Table 3). Rice & Tracey and Oyane et al. deviate respectively 60 percent and 30 percent from the 500 MPa experiment, when the C is determined in the experiment at room pressure.
Grahic Jump Location
Validity check of the proposed criterion for the tensile tests
Grahic Jump Location
Validity check of the proposed criterion for the blanking process




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In