Effect of coupled electronic and nuclear energy deposition on strain and stress levels in UO$_2$

Gaëlle Gutierrez (1) , Dominique Gosset (1) , Marion Bricout (1) , Claire Onofri (1) , Aurélien Debelle (2, 1)

1 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
2 CSNSM - Centre de Sciences Nucléaires et de Sciences de la Matière

UO2 polycrystals were irradiated in the nuclear energy-loss regime, Sn (900 keV I and 2 Mev Au ions) and also with an additional electronic energy deposition, Se (900 keV I and 36 MeV W ions simultaneously, i.e. Sn&Se). The strain/stress state exhibited by the irradiated pellets was determined by x-ray diffraction measurements. Results show that both measured strain and estimated stress are lower in the dual-beam irradiated samples, indicating that there is an ionization-induced change in the ballistically-generated-defect spectrum. Furthermore, it is shown that the thin irradiated layers maintain the lattice parameter of the pristine material in the basal plane.

Domaines: Physique [physics]

Gaëlle Gutierrez, Dominique Gosset, Marion Bricout, Claire Onofri, Aurélien Debelle. Effect of coupled electronic and nuclear energy deposition on strain and stress levels in UO$_2$. Journal of Nuclear Materials, 2019, 519, pp.52-56. ⟨10.1016/j.jnucmat.2019.03.034⟩. ⟨hal-02136517⟩