Dear @s.r.hall76331 ,
FLUKA is not capable to simulate crystal structures, only homogenous compound materials can be defined.
The DPA and temperature both depend on the beam parameters and linearly scale with the beam intensity, with the assumption that the specific heat is constant (which is not).
For an exact temperature calculation a separate, (for example) finite element simulation is required. See: Energy deposition and associated temperature - #5 by adonadon
Cheers,
David