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Crack-induced stress, dislocations and acoustic emission by 3-D atomistic simulations in bcc iron

“…9a for the present crystal orientation and plane-strain conditions. Atomistic MD simulations offer an opportunity visualize the radiation of stress waves in anisotropic crystals with defects for a relatively simple wave [11][12][13][14][15][16][17]. Moreover, such simulations provide information in the framework of the non-linear dynamic approach, since the interatomic forces are non-linear in character.…”

“…[16], the situation at the free crystal surface (1 1 0) in Fig. 10b is somewhat different for several reasons: the curved dislocations at the free sample surface have more screw character due to the surface image forces [25,26], and their motion is somewhat slower and surface waves can be generated theoretically at the free sample surfaces where plane-stress conditions r xz = r yz = r zz = 0 must be obeyed.…”

“…This potential differs slightly (parameter a 6 ) from the potential presented in Ref. [14], used also in 2-D simulations [5,15,16] dealing with dislocation emission, twinning and acoustic emission sources. As pointed out in Ref.…”

“…[11][12][13][14][15][16][17]). In this paper we focus on the acoustic emission sources caused by dislocation emissions in three dimensions, which have been not studied before.…”

Twinning and recrystallisation as crack tip deformation mechanisms during fracture

“…In addition. Cerv et ai [13] presented atomistic results showing transonic twinning generated from erack tips and micro-crueks in Fe.…”