Rate Independent Deformation Patterning in Crystal Plasticity

2015-07-01
LANCIONI, GIOVANNI
ZITTI, GIANLUCA
Yalçınkaya, Tuncay
Abstract: Metal forming processes involve continuous strain path changes inducing plastic anisotropywhich could result in the failure of the material. It has been often observed that the formation andevolution of meso-scale dislocation microstructures under monotonic and non-proportional loading have substantial effect on the induced anisotropy. It is therefore quite crucial to study the microstructureevolution to understand the underlying physics of the macroscopic transient plastic behavior. In thiscontext the deformation patterning induced by the non-convex plastic energies is investigated in amulti-slip crystal plasticity framework. An incremental variational approach is followed, which resultsin a rate-independent model exhibiting a number of similarities to the rate-dependent formulationproposed in [Yalcinkaya, Brekelmans, Geers, Int. J. of Solids and Structures, 49, 2625-2636, 2012].However there is a pronounced difference in the dissipative character of the models. The influenceof the plastic potential on the evolution of dislocation microstructures is studied through a Landau-Devonshire double-well plastic potential. Numerical simulations are performed and the results arediscussed with respect to the observed microstructure evolution in metals.
Key Engineering Materials

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Citation Formats
G. LANCIONI, G. ZITTI, and T. Yalçınkaya, “Rate Independent Deformation Patterning in Crystal Plasticity,” Key Engineering Materials, pp. 944–949, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35341.