Climb of dislocations

Growth of surface defects CS planes in catalytic reduction and climb of dislocations... 

Because the adatoms diffuse relatively rapidly along the surface and the ledges to the kinks, many more atoms reach the kinks by these routes than by direct impingement from the vapor. Note the close similarity between this crystal growth process on a vicinal surface and the climb of dislocations depicted in Fig. 11.2. 

Dislocation movement requires only a small stress compared with that required for the simultaneous movement of one atomic plane over another because only a few atoms are directly involved in the slip process at any instant (see Figure 9.2). However, at higher temperatures, edge dislocations can move out of their slip planes by a process called climb, in which atoms (or vacancies) diffuse to, or away from, the dislocation core (Figure 9.3). The climb of dislocations is, therefore, an important process in high-temperature deformation. In some materials, deformation twinning may be important, especially at low temperatures. 

Li J. C. M., Cross Slip and Cross Climb of Dislocations Induced by a Locked Dislocation, /. Appl. Phys. 32, 593 (1961). 

The deformation is believed to occur mainly by climb of dislocations, with oxygen atoms traveling along dislocation loops. Lengths of dislocation loops vary greatly but are of the order of magnitude of 1 pm. 

Narayan, J. (1972) Self-climb of dislocation loops in magnesium-oxide, Philos. Mag. 26, 1179. 

Poirier [19] points out that when the cross-slip and climb of dislocations operate at the same time, e may be written as ... 

However, the required interface action can be accomplished by the climb of dislocations belonging to the metal lattice, i.e. metal misorientation dislocations or misfit dislocations. Indeed, the jump of one metal atom from these dislocations towards one cation vacancy at the scale/substrate interface simultaneously achieves two interface requirements the consumption of the metal lattice and the annihilation of incoming cation vacancies by the climb of misorientation and/or misfit dislocations. As schematically shown in Fig. 2.7, the cUmb of misorientation dislocations would, in addition to cation vacancy annihilation, permit the required rigid body translation of the oxide lattice. However, the density of misfit dislocations usually greatly exceeds... 

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