Stress field induced by swift heavy ion irradiation in cubic yttria stabilized zirconia

X-ray diffraction (XRD) was used to investigate the damage and the correlated stress induced by the slowing down of swift heavy ions in cubic zirconia polycrystals doped with 10 mol % Y2O3. Samples were irradiated at room temperature with 940 MeV Pb ions at fluences ranging from 5x1011 to 4x1013 cm-2. Changes of XRD profiles were examined at increasing fluences. Residual macroscopic stresses induced by irradiation were determined using XRD by the ''sin2 ψ method.'' The state of stress in the irradiated layer was described by a combination of: (i) a hydrostatic stress caused by the formation of damaged tracks leading to swelling and (ii) a biaxial stress imposed by the bulk undamaged material, which controls the lateral expansion of the surface damaged layer. The evolution of the stress as a function of irradiation fluence was also determined: the intensity of the hydrostatic stress increases from 80 to 460 MPa when the fluence is increased from 5x1011 to 4x1013 cm-2 and that of the biaxial stress increases correlatively from -80 to -1630 MPa