Dislocations moving thru grain boundaries

This is work by Mike Sangid at Purdue University to study the energy barriers for dislocations to transmit through and nucleate from specific types of grain boundaries (GBs).

The pictures display comparisons of in-situ TEM (transmission electron microscopy) images with snapshots of simulations indicating the same dislocation reactions are observed in experiments and simulations, in cases of slip transmission though a sigma 13 GB (left) and sigma 19 GB (right).

The first movie displays the dislocation reaction for slip transmission with a sigma 3 GB (coherent twin). For clarity, only the atoms representing defects are shown. The second movie displays a cross-sectional view of a contour plot of the energy for the same slip-sigma 3 GB reaction.