Defining Pre-Stressed Body in Non-Linear Simulation

[feng09]

Hello FEA Champions,

i have a small problem in my FEA Study, i am working on ANSYS Workbench 13.0 trying to simulate a small 5 components assembly.
little bit of background -
Assembly is made up of metal and rubber (PTFE) components. at the time of assembly these soft component gets squashed due to there material nature and shape of the component.
in the simulation force is applied on metal part which further deflect the soft part.
I made a CAD model of an assembly in Auto desk with actual dimension which shows interference between soft part and metal part (which is obvious in CAD but not in real world scenario)
Actual problem -
i am able to resolve the contacts between metal parts but the not understanding how to define contact between these soft component and metal part .. is it going to be a bonded or friction-less or no separation (metal part and soft part can get separate under high loading condition)
also how to define pre-stresses soft component in simulation and finally how to analyse the result of the soft component

how to define this study in Ansys WB 13.0

Please share your thought on this....

many thanks in advance