  Concentrated solid--solution alloys (CSAs) in single--phase form have
recently garnered considerable attention owing to their potential for
exceptional irradiation resistance. This computational study delves into the
intricate interplay of alloying elements on the generation, recombination, and
evolution of irradiation-induced defects. Molecular dynamics simulations were
conducted for collision cascades at room temperature, spanning a range of
primary knock-on atom energies from 1 to 10 keV. The investigation encompasses
a series of model crystals, progressing from pure Ni to binary CSAs such as
NiFe$_{20}$, NiFe, NiCr$_{20}$, and culminating in the more intricate
NiFeCr$_{20}$ CSA. We observe that materials rich in chromium actively
facilitate dislocation emissions and induce the nucleation of stacking fault
tetrahedra in the proximity of nanovoids, owing to Shockley partial
interactions. This result is validated by molecular static simulations, which
calculate the surface, vacancy, and defect formation energies. Among various
shapes considered, the spherical void proves to be the most stable, followed by
the truncated octahedron and octahedron shapes. On the other hand, the
tetrahedron cubic shape is identified as the most unstable, and stacking fault
tetrahedra exhibit the highest formation energy. Notably, among the materials
studied, NiCr$_{20}$ and NiFeCr$_{20}$ CSAs stood out as the sole alloys
capable of manifesting this mechanism, mainly observed at high impact energies.
