Radiation effects on MgAl2O4-stabilized ZrO2 composite material under He+ or Xe2+ ion irradiation

The damage evolution processes in polycrystalline MgAl2O4-yttria-stabilized ZrO2 (YSZ) composite materials were studied in a TEM. The irradiations were performed with 60 keV Xe2+ ions at a flux of 5 x 10(12) ions/cm(2) s or 35 keV He+ ions at a flux of 5 x 10(13) ions/cm(2) s at room temperature and 650 degrees C, respectively. Preferential bubble formation at grain boundaries was observed in all irradiation conditions. Stress associated with the different swelling rate between MgAl2O4 and YSZ grains would cause the grain boundary cracking. Differences in damage accumulation process between MgAl2O4 and YSZ grains were clearly shown under He+ ion irradiation at 650 degrees C. Bubbles in YSZ grains remarkably grew large by coalescence during annealing process compared to those in MgAl2O4 grains, (C) 2000 Elsevier Science B.V. All rights reserved.