| Abstract: | We have created a computer simulation of dislocation loop emission by a Frank-Read source and its evolution in a uniform field
of randomly distributed, weak, point obstacles. We discovered a threshold source length such that dislocation loops from shorter
sources expand in a super-obstacle regime; otherwise they enlarge by thermal activation, and there is a relationship to the
strength of the obstacle. We determine the range of stresses in which dislocation loops expand above the obstacle, shrink,
or grow via thermal activation. In contrast with infinite linear dislocations, we do not observe stable evolution (i.e., velocity
and other characteristics) of dislocation loops in all stress regimes.
Tomsk State Architectural-Construction Academy. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp.
61–64, June, 1997. |
