Hemming is a well-known technology used by the automotive industry to join
inner and outer door panels. The accuracy of the operation affects significantly
the appearance of the car’s outer surfaces. Any defects such as surface deflection or twist
may result in costly decisions; for example, the product may be rejected during the final stage of production.
There are severe difficulties in the simulation of such problems - in addition to the
large deformations, there are difficult contact conditions.
In our simulation, ninety 9-node u/p elements are used for the outer panel and 43
elements for the inner panel. Despite the complexity of the process, a stable
convergence in the incremental solution was achieved.