Hyperplasticity: Enhanced formability at high rates
Abstract
Literature developed in the 1950's and 60's suggested that high forming velocities can lead to improved ductility and formability. However few models exist that can predict the change in material formability and it appears that this effect has rarely been put to use in practical metal forming. This report shows that very large increases in the formability of three materials is observed in the electrohydraulic forming of a conical section and moderate increases are observed in the electromagnetic expansion of aluminum rings. The ductility increase in the latter case is predicted well by a one dimensional finite element model.
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