α Self-irradiation Effects on Structural Properties of (U,Am)O2±δ Materials

Florent LEBRETON, Denis HORLAIT, Damien PRIEUR, Philippe MARTIN, Jean-Yves COLLE, Arne JANSSEN, Thierry WISS, Andreas SCHEINOST, Thibaud DELAHAYE CEA-DEN-DTEC, Service d’Etudes des Combustibles et materiaux a base d’Actinides, SECA, (Marcoule, France) CEA-DEN-DTEC, Service de Developpement des Technologies du Cycle, SDTC, (Marcoule, France) European Commission, Joint Research Centre, Institute for Transuranium Elements (Karlsruhe, Germany) Helmholtz Zentrum Dresden Rossendorf (HZDR), Institute of Resource Ecology (Dresden, Germany) CEA-DEN-DRCP, Service d’Etude du Recyclage des combustibles et d’Analyses, SERA, (Marcoule, France) Am isotopes are amongst the largest contributors to the radiotoxicity and heat load of spent nuclear fuels, especially in scenarios including plutonium recycling in MOX fuels. Transmutation in heterogeneous mode is a promising option to lower Am inventory in the ultimate nuclear waste, thus decreasing the ecological impact of deep-geological repository sites. It consists in the irradiation Ambearing blankets (AmBB, i.e., U1-xAmxO2±δ with x values close to 10-15 at.%) in the periphery of a fast neutron reactor core. In this context, studies are being performed to assess the feasibility and safety of AmBB transmutation, notably focusing on innovative fabrication processes [1–3], AmBB behavior under irradiation [4] and U1-xAmxO2±δ properties [5]. Am being a strong α emitter (activity of 130 MBq), U1-xAmxO2±δ behavior under α self-irradiation is also monitored [6–8].