G. Schoeck et W. Puschl, DISSOCIATED DISLOCATIONS IN THE PEIERLS POTENTIAL, Materials science & engineering. A, Structural materials: properties, microstructure and processing, 189(1-2), 1994, pp. 61-67
Dislocations in close-packed lattices dissociated in two partial dislo
cations show a complex behaviour when moving over a periodic Peierls p
otential. Several equilibrium states are possible, and the energy barr
ier to motion of the combined system depends on the exact equilibrium
separation of the partials, very sensitively so when they are strongly
coupled. In this case the effective Peierls potential varies between
zero and twice the potential for an individual partial. This mechanism
may resolve an old discrepancy between low-temperature flow stress an
d the Peierls stress as deduced from internal friction measurements.