Phase Transformations Under High Pressure and Large Plastic Deformations: Multiscale Theory and Interpretation of Experiments

Slip of shuffle screw dislocations through tilt grain boundaries in silicon

“…Since the energy barrier for crossing all the GBs at the heptagon sites is only slightly larger than the Peierls barrier for the dislocation motion in bulk, perfect screw dislocations cannot pile up against these GBs and cannot reduce phase transformation pres- sure during plastic deformations [9,10]. At the same time, all GBs produces 60 o dislocation pile-up, which essentially reduces the transformation pressure from Si I to Si II under shear [24,25].…”