The cylindrical block is modeled using 396 plane elements (PLANE182) with axisymmetric behavior (element key option KEYOPT(3) = 1). Options for full integration with the B-bar method (KEYOPT(1) = 0) and mixed u-P formulation (KEYOPT(6) = 1) are also specified.
et,1,182 keyopt,1,1,0 ! B-bar method (default) keyopt,1,3,1 ! Axisymmetric keyopt,1,6,1 ! Mixed u-P formulation
The B-bar method and the mixed u-P formulation prevent the volumetric locking that can be triggered by large plastic deformation. Following is the initial finite element model with loading and boundary conditions applied:
Two rigid-deformable contact pairs without friction are defined using target and contact elements (TARGE169 and CONTA172, respectively) with the Augmented Lagrangian formulation (KEYOPT(2) = 0) activated.
The contact stiffness is updated at each iteration (KEYOPT(10) = 2).
The first contact pair is defined between the top die (moving) and the top and right edges of the work piece. The second contact pair is defined between the bottom die (static) and the bottom and right edges of the work piece.