Dislocation structure of cementite in granular pearlite after cold plastic deformation

Transmission electron microscopy of dislocations in cementite deformed at high pressure and high temperature

“…Our study highlights the importance of [1 0 0] and [0 0 1] slip in the plasticity of cementite. We observe that [1 0 0] dislocations are dissociated in agreement with our theoretical prediction (Garvik et al [5]) and with the observation of activation of partial [1 0 0](0 1 0) dislocations in cementite deformed at low temperature (Keh [15] and Karkina et al [14]). The strengthening role played by cementite in pearlitic steels would thus also be controlled by the morphology.…”

“…However, the Peierls Nabarro model suggests two asymmetric partials which may experience different lattice frictions (Garvik et al [5]). At lower temperature and under high stress, the two partials may de-correlate leading to a deformation by partials as observed by Kar'kina et al [14] (also probably reported by Keh [15] although some ambiguity remain on the plane containing the stacking fault reported in their work where the space group used is not precised).…”

“…They found mostly [1 0 0] dislocations. More recently, Kar'kina et al [14] showed that, at the early stages of deformation of granular pearlite, carbide particles are deformed by partial [1 0 0] dislocations. Our study does confirm the importance of [1 0 0] glide in the plasticity of cementite.…”

“…[1 0 0], [0 1 0] and [0 0 1]) have been proposed [10,11,17,27], but detailed characterisations are scarce. In a recent study, Kar'kina et al [14] have drawn attention on the contribution of partial [1 0 0] dislocations gliding in (0 1 0) in cold plastic deformation of cementite in granular pearlite.…”

Mechanisms of subgrain coarsening and its effect on the mechanical properties of carbon-supersaturated nanocrystalline hypereutectoid steel

“…5(b) reveals stacking faults in the cementite. Since stacking faults are usually introduced by plastic deformation of cementite [37][38][39], the stacking faults observed here in the annealed sample are probably inherited from the cementite that remained after cold drawing. This result suggests that part of the remaining cementite may still maintain its crystalline structure after cold drawing.…”