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Abstract:
The
wrinkling strength of shell in cup deep-drawing process without
blankholder through a conical die is deduced by using the well-known
energy method. The formula mirrors the effect of material properties,
radial and circumferential bending, varying thickness and work-hardening
on the wrinkling strength. Predicted limiting drawing ratios without
wrinkling on the basis of the strength are completely in agreement with
the experimental results of cup deep-drawing without blankholder through
a conical die, which are obtained by Sowerby et al. Who used three
metals in three different sheet thicknesses. Their maximum relative
error is not more than eight percent. The study method is also suited to
analyze cirumferential compressive instability in the area of hanging in
the air between punch and die for axisymmetrical no-straight wall parts.
Key words:
Deep-drawing Wrinkling Bending Instability
CLC No: TG381
江苏省教育厅自然科学基金资助项目. Received
20001009, received in revised form 20010226
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