Formability of sheet metals is often assessed by means of forming limit diagrams (FLD). In this paper, performing three different series of experiments, the effect of forming velocity on FLDs is investigated experimentally for Al 6061-T6 and AISI 1045 sheets. In addition to determining the conventional FLDs at quasi-static condition (
The results show that while a substantial improvement in high strain rate formability of the aluminium sheet can be obtained, this improvement is not considerable for the steel sheets. Also, under the effect of contact pressure between tool and sheet, the formability increases for both steel and aluminium sheets on impact.
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