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Fig. 9 Density estimates (smoothed histograms) of pressure at all computational points in the 10
statistical volume element polycrystal simulations at the conclusion of the loading profile given in
Fig. 5
structural features on the stress variability within the grain. These results suggest
that the variation of vonMises stress within the grain is much more heterogeneous
in the vicinity of the grain boundary with some locations about 40% higher than the
more stable mean value towards the grain center. The variability drop is more rapid
in the case of the grain boundary surface than for the grain boundary triple line. It
is also interesting to note that the converging vonMises stress magnitude is different
for the two grains. This magnitude is approximately 740 MPa for grain 45 and
approximately 800 MPa for the case of grain 53. This is likely due to neighborhood
effects within the polycrystal and also differences in crystallographic orientation
between the two grains. The results shown in Fig. 5 show that the loading is not
purely hydrostatic, but the stress magnitude in the shock direction is 10% higher
than the two other principal directions.