Non-convex rate dependent strain gradient crystal plasticity and deformation patterning

2012-09-15
Yalçınkaya, Tuncay
Geers, M.G.D.
A rate dependent strain gradient crystal plasticity framework is presented where the displacement and the plastic slip fields are considered as primary variables. These coupled fields are determined on a global level by solving simultaneously the linear momentum balance and the slip evolution equation, which is derived in a thermodynamically consistent manner. The formulation is based on the 1D theory presented in Yalcinkaya et al. (2011), where the patterning of plastic slip is obtained in a system with non-convex energetic hardening through a phenomenological double-well plastic potential. In the current multidimensional multi-slip analysis the non-convexity enters the framework through a latent hardening potential presented in Ortiz and Repettto (1999) where the microstructure evolution is obtained explicitly via a lamination procedure. The current study aims the implicit evolution of deformation patterns due to the incorporated physically based non-convex potential.
International Journal of Solids and Structures

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Citation Formats
T. Yalçınkaya and M. G. D. Geers, “Non-convex rate dependent strain gradient crystal plasticity and deformation patterning,” International Journal of Solids and Structures, pp. 2625–2636, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35665.