Deep Drawing of a Cup
Deep drawing is a forming process in which a blank of sheet metal is drawn into a die by a moving punch. The blank is clamped by a blank holder against the die. The deep drawing process takes place slowly such that inertial effects are negligible and it can be termed as quasi-static. Quasi-static problems can be simulated well with either Abaqus/Standard or Abaqus/Explicit. Typically, quasi static problems are solved with Abaqus/Standard but may face convergence difficulties due to contact or other nonlinearities. Such problems are a good candidate to be solved with Abaqus/Explicit as explicit procedure can resolve complicated contact problems and other discontinuous nonlinearities more easily than Abaqus/Standard.
This is a challenging problems as it involves multiple nonlinearities: material nonlinearity, geometric nonlinearity and contact between multiple components. By taking advantage of the symmetry, only a quarter of the blank will be considered for simulation.
The analysis is completed in two steps. In the first step, a load is applied on the holder and in the second step the punch is moved downwards
In the first step, as a load is applied on the holder compressive stresses are induced in the blank as shown in the figure.
In the second step the punch is moved downwards by applying a boundary condition. Very high stresses are generated in the blank during this step.
During second step, material undergoes high plastic strains. The figure shows the distribution of equivalent plastic strain at the end of the step.
Significant changes in the thickness of blank take place. The contour plots show that in some areas thickness of blank has increased while in other areas thickness has reduced.
The following animation shows the evolution of von Mises stresses, plastic strains and changes in balnk thickness.