“…Despite significant advantages of in-situ irradiations, some issues still remain in the evaluation of the effects of free surfaces in thin foils. Such effects are discussed in some studies in face-centered cubic (fcc) materials (nickel, copper, tungsten and austenitic stainless steels (ASSs)) [4,[6][7][8][9]. As strong sinks for point defects, free surfaces affect significantly the defect formation and evolution in thin-foil samples.…”