AbstractRadiation damage is an important issue in the lifetime of the structural materials in an Inertial Fusion Energy (IFE) Reactor. The effect will strongly depend on the class of chamber protection at the IFE Reactor design. This paper gives results from DENIM, and collaboration with LLNL, on the necessary magnitudes for the final evaluation of neutron damage. The determination of the neutron intensities and energy spectra emerging from the target, the energy spectra of the Primary Knock-on Atoms (PKA) resulting from the neutron interactions, the modeling at microscopic scale of the pulsed irradiation in metals are reported, in addition to reference to the work on the time dependence of neutron flux in IFE protected chamber. Results are also presented on the damage accumulation in SiC, relevant both for magnetic (MFE) and inertial fusion.