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Determination of Forming Limits in Automotive Stampings
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Sector:
Event:
Mid-Year Meeting
Language:
English
Abstract
Forming limits are determined by analyzing strain distributions obtained from 0.2–0.05 in. grids imprinted on blanks by photographic or electrochemical marking techniques. Failure generally occurs in a region of stretch forming where all strains are positive (tensile) in the plane of the sheet. Experimental results derived from laboratory specimens and production automotive stampings indicate a predictable critical strain level beyond which failure is anticipated. The most effective method of increasing the stretching limits is the development of a more nearly uniform strain distribution. Factors controlling this distribution are material strain hardening characteristics, die design, stamping geometry, and lubrication.
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Authors
Citation
Keeler, S., "Determination of Forming Limits in Automotive Stampings," SAE Technical Paper 650535, 1965, https://doi.org/10.4271/650535.Also In
References
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