Plastic slip patterns through rate-independent and rate-dependent plasticity

Lancioni, Giovanni
Yalçınkaya, Tuncay
Plastic deformation induces various types of dislocation microstructures at different length scales, which eventually results in a heterogeneous deformation field in metallic materials. Development of such structures manifests themselves as macroscopic hardening/softening response and plastic anisotropy during strain path changes, which is often observed during forming processes. In this paper we present two different non-local plasticity models based on non-convex potentials to simulate the intrinsic rate-dependent and rate-independent development of plastic slip patterns, which is the simplified mechanism for the intrinsic microstructure development. For the sake of mechanistic understanding, the formulation and the simulations will be conducted in one-dimension which does not exclude its extension to multi-dimensions resulting in a crystal plasticity framework.


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At grain scale, polycrystalline materials develop heterogeneous plastic deformation fields, localizations and stress concentrations due to variation of grain orientations, geometries and defects. Development of inter-granular stresses due to misorientation are crucial for a range of grain boundary (GB) related failure mechanisms, such as stress corrosion cracking (SCC) and fatigue cracking. Local crystal plasticity finite element modelling of polycrystalline metals at micron scale results in stress jumps at...
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Yalçınkaya, Tuncay; Geers, M.G.D. (2012-09-15)
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 no...
Crystal plasticity modeling of additively manufactured metallic microstructures
Acar, Sadik Sefa; Bulut, Orhun; Yalçınkaya, Tuncay (2021-01-01)
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Orhun, Bulut; Yalçınkaya, Tuncay; Department of Aerospace Engineering (2022-6-14)
In this thesis, two important microstructural phenomena affecting the plastic behavior of metallic materials are addressed through a local crystal plasticity modeling framework. Initially the influence of anisotropic grain structure developing during various forming procedures and additive manufacturing processes is studied following a multiscale modeling strategy, where Representative Volume Elements (RVEs) are analyzed under axial loading conditions. Macroscopic response of different degrees of anisotropi...
Citation Formats
G. Lancioni and T. Yalçınkaya, “Plastic slip patterns through rate-independent and rate-dependent plasticity,” 2014, Accessed: 00, 2020. [Online]. Available: