  Al$_x$Ga$_{1-x}$N materials have become increasingly important for
electronics in radiation environments due to their robust properties. In this
work, we aim to investigate the atomistic mechanisms of radiation-induced
damage in AlGaN compounds, providing insights that bridge the gap between
high-length-scale experimental data and detailed atomic-level processes.
Through extensive molecular dynamics simulations, we reveal the compositional
dependence of radiation-induced defect production in Al$_x$Ga$_{1-x}$N systems
with $x$ ranging from 0 to 1. The damage accumulation characteristics observed
in our simulations align notably well with available experimental data at
temperatures up to room temperature. Our findings indicate that alloy
composition significantly influences defect production and microstructural
evolution, including the formation of dislocation loops and defect clusters.
Specifically, with increasing Al content, defect production from individual
recoil events is reduced; however, extended interstitial defects are more
likely to form considering cumulative effects, leading to enhanced damage at
high doses. Among the compositions studied, we find that 25\% Al content leads
to the least overall radiation damage, suggesting an optimal alloying strategy
for mitigating radiation effects. These findings underscore the interplay
between defect formation, dynamic annealing, and cascade effects, offering
insights for optimizing AlGaN materials for radiation resistance in practical
applications.
