非表示:
キーワード:
anisotropy, crystal, plasticity, simulation, texture, finite element method, mechanics, anisotropy, metals, structural behavior, mechanical properties, grain interaction, orientation fragmentation
要旨:
Deformation of a grain in polycrystalline metals is restricted or forced by
deformation of neighbor grains during plastic deformation processes. It
also gives influence to deformation of neighbor grains at the same time.
Interaction between grains causes inhomogeneous local deformation and
texture during plastic deformation. Prediction of inhomogeneous local
deformation and texture is important in understanding of recrystallization
texture. Taylor-type polycrystal models which have been employed in
prediction of texture evolution do not account for grain interaction. In this
work, a finite element simulation based on the crystal plasticity has been
carried out to investigate the effect of grain interaction on local
deformation and texture evolution. An artificially configured BCC bicrystal
that consists of a crystal located at center and a surrounding neighbor
crystal has been employed in plane strain compression simulation. Several
pairs of specific orientations have been chosen for initial orientations of the
bicrystal. Deformation and texture evolution of the center crystal in the
bicrystal have been investigated changing the initial orientation of the
surrounding crystal. The simulation results show that deformation and
texture evolution near crystal boundary can be different from those at the
center region of the crystal. Orientation fragmentation, which results in
great lattice curvature is observed in a center grain with an initial
metastable orientation. Simulation shows that a metastable crystal always
breaks up during deformation and the grain interaction changes only the
pattern of grain breakup.
