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Free keywords:
anisotropy, crystal, plasticity, simulation, texture, finite element method, mechanics, anisotropy, metals, structural behavior, mechanical properties
Abstract:
We present plane strain simulations about the dependence of
orientational in-grain subdivision and crystallographic deformation
textures in aluminium polycrystals on grain interaction. The predictions
are compared to experiments. For the simulations we use a crystal
plasticity finite element and different polycrystal homogenization models.
One set of finite element simulations is conducted by statistically varying
the arrangement of the grains in a polycrystal. Each grain contains 8
integration points and has different neighbor grains in each simulation.
The reorientation paths of the 8 integration points in each grain are
sampled for the different polycrystal arrangements. For quantifying the
influence of the grain neighborhood on subdivision and texture we use a
mean orientation concept for the calculation of the orientation spread
among the 8 originally identical in-grain orientation points after plastic
straining. The results are compared to Taylor-Bishop-Hill-type and
Sachs-type models which consider grain interaction on a statistical basis.
The progress report reveals five important points about grain interaction.
First, the consideration of local grain neighborhood has a significant
influence on the reorientation of a grain (up to 20% in terms of its end
orientation and its orientation density), but its own initial orientation is
more important for its reorientation behavior than its grain
neighborhood. Second, the sharpness of the deformation texture is
affected by grain interaction leading to an overall weaker texture when
compared to results obtained without interaction. Third, the in-grain
subdivision of formerly homogeneous grains occurring during straining is
strongly dependent on their initial orientation. [...]