ON THE NUMERICAL TREATMENT AND ANALYSIS OF FINITE DEFORMATION DUCTILESINGLE-CRYSTAL PLASTICITY

This contribution is concerned with the numerical analysis and simulat ion of instability phenomena such as shearband localization in plastic flow processes within the framework of ductile single (fee) crystal v iscoplasticity. To this end, a family of implicit constitutive algorit hms and their implementation are considered in detail. Issues of accur acy and conservation of plastic incompressibility are examined. Moreov er, the implementation within an overall Newton-Raphson finite element solution strategy relies an the correct evaluation of the algorithmic tangent moduli which result from linearizing the stress update integr ator. Likewise, these algorithmic tangent moduli are employed within t he numerical analysis of the spatial localization tenser. Examples dem onstrating the performance of the proposed strategy at the local const itutive level as well as at the global structural level are given.