A student is planning to perform a bending operation as shown in the schematic below. The upper and bottom die will close to bend the sheet metal. Prior to the operation, the student performed a tensile test using the same material. A specimen of Æ20 mm diameter was used, and the final failure diameter was Æ17.5 mm. Failure at two locations, (A) and (B), are of interest. R is the corner radius of the dies.
Estimate the largest engineering strain experienced by the sheet metal during the operation.
Is this bending operation feasible without sheet failure?