High-resolution electron-microscopy study of 60°-Dislocations in Cu

Abstract

Dissociated 60°‐dislocations in Cu are imaged by high‐resolution transmission electron microscopy (HRTEM). From the separation of the partial dislocations a room‐temperature stacking‐fault free energy (SFE) of (40 ± 8) mJ/m2 is deduced. This value corresponds well to the results obtained by the weak‐beam technique, in which thicker specimen foils are used. Considered together with results on other materials, this indicates that the determination of the SFE by HRTEM is possible if the SFE is not extremely low and if 60°‐dislocations are used for the analysis.

An EAM potential for α-brass copper–zinc alloys: application to plasticity and fracture

“…The dissociation distance lying at 5.2 nm for both potentials. One note that both predicted distances are higher than the experimentally measured one [53]. When adding the alloying effect, the dissociation distance is close to the one computed from elastic theory incorporating the ISF as given in Hirth and Lothe [52].…”

“…As seen in figure 12, the dissociation distance increases with the zinc concentration and correlates with the decrease of the ISF energy. Moreover, the distance obtained was compared to previous literature results [53,54] and with the elastic theory. The result with the new potential fits very closely with Aslanides and Pontikis [54] results for copper.…”

HRTEM study of defects in twin boundaries of ultra-fine grained copper

“…separated by a ribbon of a stacking fault. The dissociation width is estimated to range between 2.7 and 4.7 nm in copper [33]. In the present case, the two partials are too close to clearly observe the dissociation.…”

“…Moreover, if the transmission criteria may be "easily" applied to perfect lattice dislocation, in case of low stacking fault materials, the entrance into the GB of partial dislocations whose Burgers vectors do not necessarily belong to the DSC lattice implies complex processes 18 [33,34,[46][47][48]. In most cases, an "indirect" transmission operates, implying absorption of lattice dislocations from one crystal followed by reaction within the GB and emission of lattice dislocations in the other crystal.…”

Numerical study of the athermal annihilation of edge-dislocation dipoles

“…The cohesion energy E c values are taken from Kittel (1976). The intrinsic stacking-fault energies ® i are taken from Hammer et al (1992) (ab-initio calculation for aluminium) and Weiler et al (1995) (experimental for copper). The intrinsic stacking-fault energies ® i are taken from Hammer et al (1992) (ab-initio calculation for aluminium) and Weiler et al (1995) (experimental for copper).…”