**3.1 Radiation damage characterization**

Characterization of irradiation effects in materials using heavy or lesser ion beams is not new; it has been used for more than a decade. Tests with protons, for example, have gotten a lot of attention. Such experiments have been used as stand-ins for research into radiation in various nuclear materials. Yet, as the year passes and materials continue to fail under particular situations, the necessity to identify new materials to fit into such applications becomes more critical. Some programs and earlier studies

have been successful in identifying materials suitable for use in nuclear reactor system design using the IBT.

Positron Annihilation Spectroscopy (PAS) experiments have also been used effectively to evaluate radiation damage in nuclear materials. Sabelová et al. [24] used positron annihilation techniques to analyze helium-implanted Fe-Cr alloys. Similarly, A review study by [25] stipulated and disclosed a lot of work on the use of positron annihilation in characterizing materials when it comes to radiation damage. The employment of a positron, according to the study by [25], is the only investigation that can precisely determine the size, concentration, and chemical makeup of individual atomic vacancies, as well as microscopic and large vacancy clusters formed by irradiation. The PAS was further supported by the study due to its extraordinary sensitivity to lattice defects. Doppler broadening spectroscopy, which refers to the widening of spectral lines induced by the Doppler effect, has also been utilized extensively together with PAS to evaluate materials.

Another approach used to characterize radiation damage in materials is a focused ion beam (FIB) [26–28]. It is comparable to Scanning Electron Microscopy (SEM), which has long been used in this capacity, but whereas SEM employs a focused beam of electrons to photograph the material in the chamber, a FIB apparatus utilizes a concentrated beam of ions. FIB may also be used in systems that include both electron and ion beam columns, enabling the same feature to be examined with either beam. It is one of the current applications of ion beams in characterization which is mostly deployed in the health sector but it is equally important in the spheres of nuclear materials damage assessment.

Transmission electron microscopy (TEM), atom probe tomography (APT), synchrotron radiation methods, micro-X-ray diffraction (XRD), and small-angle neutron scattering (SANS) are all potent techniques used to characterize radiation damage. All of these approaches use ion beam technology throughout the characterization process.
