Peculiar behavior of structure rearrangement in nanofiber of intermetallic Ni3Al, containing long-period paired thermal anti-phase boundaries, under high-rate tensile uniaxial loading along <001>

Abstract

Using molecular dynamics simulations, peculiarities of structure rearrangement in nanofiber of intermetallic Ni 3 Al containing long-period, paired, thermal (nonconservative) anti-phase boundarties (APBs is investigated in the course of high-rate, tensile uniaxial loading along <001>. Four main deformation stages are determined (quasi-elastic, plastic, material flow and rupture), with each stage revealing particular features of structure transformations and energy transfer. The presence of periodic thermal planar defects in the long-period nanostructure (combined thermal anti-phase boundaries) significantly affects the onset of plastic deformation. A change in the type of thermal APBs in the long-period structure in turn affects the time to total rupture of nanofiber under plastic deformation condition. For the thermal АА 1/2<110>{001}APBs, the time to total nanofiber rupture is slightly decreased, while that for the thermal АВ 1/2<110>{001} APBs is considerably increased.

Modeling the Deformation of FCC Nickel Nanowires which Contain Hydrogen Atoms

“…corresponded to the emergence of new structural defects and the displacements of the nanowire's parts towards each other. Similar situation was noticed during the deformation of nanowire Ni3Al previously simulated by molecular dynamics [4][5][6]. Clusters of hydrogen atoms are formed during plastic deformation.…”

“…5). The results showed a higher max strength value for Ni nanowires containing hydrogen as compared with the results previously obtained for Ni nanowires without hydrogen [5][6]. As can be seen from Fig.…”

“…The following conclusions can be formulated on the basis of the calculations. The results showed a higher value for max strength Ni nanowires containing hydrogen as compared with the results previously obtained for Ni nanowires without hydrogen [5][6]. Structural features and energy transformations in Ni nanowires containing hydrogen, is the appearance at the stage of plastic deformation of globular formations of hydrogen atoms.…”

“…The appearance of clusters of hydrogen atoms affects the atomic displacement processes during deformation led to the increase in the duration of II and III deformation stages (Fig. 1-4) in comparison with the results for nanowires Ni without hydrogen [4][5][6]. At T=900 K pronounced increasing third stage duration (Fig.…”

“…The effects of the energy exchange of the model system with the surrounding medium were included using a special algorithm of velocity scaling -Berendsen thermostat [3]. The thermostat was applied earlier at deformation simulation of the nanowires of FCC [4][5][6] and FCT [7] metals and alloys.…”