Sammendrag
The crystal plasticity finite element method has been used in combination with
crystallographic texture data to predict the plastic anisotropy of the extruded
aluminium alloy AA6063 in temper T6. The results are compared with
experimental data from tensile tests at different angles between the tensile
and extrusion directions. Inverse modelling based on the tensile test in a
reference direction is used to identify the parameters of the work-hardening
model at slip system level. To investigate the influence of grain interactions,
various discretizations of the grains are applied in the representative volume
element modelled with finite elements. In addition, alternative homogenization
schemes, such as the full-constraint Taylor and viscoplastic self-consistent
methods, are used to model the behaviour of the polycrystal. It is found that the
grain discretization and the homogenization scheme have only minor influence
on the predicted plastic anisotropy. While the crystal plasticity-based methods
all give reasonable predictions of the directional variations of flow stresses
and plastic strain ratios measured experimentally, there are still significant
deviations, indicating there are other sources to the plastic anisotropy than
crystallographic texture.
crystallographic texture data to predict the plastic anisotropy of the extruded
aluminium alloy AA6063 in temper T6. The results are compared with
experimental data from tensile tests at different angles between the tensile
and extrusion directions. Inverse modelling based on the tensile test in a
reference direction is used to identify the parameters of the work-hardening
model at slip system level. To investigate the influence of grain interactions,
various discretizations of the grains are applied in the representative volume
element modelled with finite elements. In addition, alternative homogenization
schemes, such as the full-constraint Taylor and viscoplastic self-consistent
methods, are used to model the behaviour of the polycrystal. It is found that the
grain discretization and the homogenization scheme have only minor influence
on the predicted plastic anisotropy. While the crystal plasticity-based methods
all give reasonable predictions of the directional variations of flow stresses
and plastic strain ratios measured experimentally, there are still significant
deviations, indicating there are other sources to the plastic anisotropy than
crystallographic texture.