SMALL PUNCH TECHNIQUE USED TO EVALUETE THE SS316L THIN FOILS DUO TO PROTON BOMBARDMENT

The mechanical properties characterization of thin foils (~25 µm) to be used as target in high intensity accelerator requires non standards techniques. In a previous study, focused on annealed foils as received, after cold rolling foils, and after heat treatment foils, was carried out to test mechanical properties of the different metallurgical stage of foils and characterize the capability of the small punch technique (SPT). The non-irradiated samples were characterized subsequently by X-ray diffraction (XRD), and transmission-scanning electron microscopy (TEM). The SPT technique revealed that the annealed specimens exhibited the largest load to failure and deformation, rather than the cold rolled and heat treated foils. The microscopy observations revealed high dislocation density following by cold rolling and subsequent heat treatments. After annealing, a cubic crystallographic structure (FCC) with equiaxed grains and a limited dislocation population was observed. After cold rolling and subsequent thermal treatment, a preferred orientation texture was observed with a very high dislocation density. The mechanical behavior of the foils can be explained by the microstructural obtained. In this new study, samples of as received foils submitted to proton bombardment at 3.6 MeV, 300mA during 3 and 40 hours were characterized by the SPT technique. Changes obtained on the SPT measurements characterization are attributed to the radiation damage.