This work is dealing with the understanding of the corrosion mechanisms at solid/solution interface and taking into account for the 4 He 2+ ions irradiation effects on these mechanisms. These corrosion and 4 He 2+ ions radiolysis phenomena append at solid/solution interface and will be studied at a μmetric scale by the Raman spectroscopy. Moreover, a 4 He 2+ ions irradiation appends onto a low volume and let us to control the irradiated area (solution, solid or interface). For the solid, th e chemical species induced by 4 He 2+ ions radiolysis of water are such reactive and are involved in classical corrosion mechanisms of UO 2 . Moreover, we want to study the impact of the 4 He 2+ ions radiolysis of water laye rs physisorbed into the surface onto corrosion mechanisms. That is the reason w hy we want to use a local irradiation, allowed by the 4 He 2+ ions ion beam provided by the ARRO NAX cyclotron (E = 64.7 MeV). In this work an experimental apparatus will be perf ormed in order to characterize solid/solution interface at μmetri c scale by Raman spectroscopy under 4 He 2+ ions irradiation provided by the cyclotron ARRONAX facility. Th e leaching experiments under ir radiation will be performed for a short time in order to study the parameters during the fast instant release step. The grain boundaries effect will be studied by the compar ison between one TRISO particles set (solids with grain boundaries) and one TRISO particles set previously washed by one acid solution (solid without grain bounda ries). The role of H 2 will be studied by the comparison between experiments under Ar or Ar/H 2 atmosphere. The dose rate range will be between 0 and 100 Gy/min by using the alpha ion beam which let us control the dose set down into the sample. For all these experiments, measur ements will be performed by the in situ Raman spectroscopy during the irradiation in order to follow the formation/consumption of the secondary phases formed onto the solid. The SEM will be perf ormed in order to characterize the grain boundaries and the secondary phases formed by the leaching/irradiation experiments. The μGC is used to measure the P H2 into the irradiation cell to follow the production/consumption of this gaseous species formed by the water radiolysis and consumed by the leaching process.