  We demonstrate a practical way to perform decomposition of the elasto-plastic
deformation directly from atomistic simulation snapshots. Through molecular
dynamics simulations on a large single crystal, we elucidate the intricate
process of converting plastic strain, atomic strain, and rigid rotation during
irradiation. Our study highlights how prismatic dislocation loops act as
initiators of plastic strain effects in heavily irradiated metals, resulting in
experimentally measurable alterations in lattice strain. We show the onset of
plastic strain starts to emerge at high dose, leading to the spontaneous
emergence of dislocation creep and irradiation-induced lattice swelling. This
phenomenon arises from the agglomeration of dislocation loops into a
dislocation network. Furthermore, our numerical framework enables us to
categorize the plastic transformation into two distinct types: pure slip events
and slip events accompanied by lattice swelling. The latter type is
particularly responsible for the observed divergence in interstitial and
vacancy counts, and also impacts the behavior of dislocations, potentially
activating non-conventional slip systems.
