The deformation behaviour of nano-sized Ni

3

Al cubes with {100} side surfaces is investigated under uniaxial compression using constant-temperature molecular dynamics simulations at 300 K. The simulations reproduce key features of recently performed nanocompression experiments

namely the lack of strain hardening

homogeneous deformation of the enti

re sample and overall high stress levels of the order of 3–5 GPa. According to the simulations

the critical initial step is the formation of a pseudo-twin structure

which then further deforms by Shockley partial dislocations. These deformation mechanisms differ significantly from bulk Ni

3

Al and are rationalized in terms of generalized stacking fault energies and resolved shear stresses.