Oxide dispersion strengthened steels are candidate materials for nuclear reactor applications due to a powerful combination of properties, such as reduced activation, high-temperature strength and increased creep resistance. The dispersion of nanometric oxide particles in the steel matrix may also enhance radiation resistance by acting as trapping sites for irradiation induced defects. In this work, an Fe–14Cr–2 W–0.3-Ti–0.3Y₂O₃ (wt%) steel and a model Fe-14Cr (wt%) alloy were sequentially irradiated with He⁺ and Fe⁺ ions up to 15 dpa and 8000 appm to simulate fusion radiation damage. Their microstructural stability was investigated by positron annihilation spectroscopy and transmission electron microscopy. Transmission electron microscopy studies show that under these irradiation conditions there are no significant changes in the mean size, qualitative chemical composition and number density of nanoparticles, although the irradiation appears to induce a slight coarsening of the smaller nanoparticles. Both materials exhibit very small (<2 nm) irradiation-induced bubbles, with similar sizes but lower number density in the ODS steel. Positron annihilation spectroscopy results show the presence of irradiation induced open volume defects, much more noticeable in the model alloy. In both alloys, helium appears to associate with the newly formed vacancy-type defects introduced by the subsequent Fe⁺ irradiation.

氧化物弥散强化钢由于其强大的性能组合（例如降低的活化度，高温强度和更高的抗蠕变性）而成为核反应堆应用的候选材料。纳米氧化物颗粒在钢基质中的分散还可以通过充当辐射诱发缺陷的俘获位点来增强抗辐射性。在这项工作中，依次用He ⁺和Fe ⁺辐照Fe–14Cr–2 W–0.3-Ti–0.3Y ₂ O ₃（wt％）钢和Fe-14Cr（wt％）模型合金。高达15 dpa和8000 appm的离子来模拟聚变辐射损伤。通过正电子an没光谱和透射电子显微镜研究了它们的微观结构稳定性。透射电子显微镜研究表明，在这些辐照条件下，纳米颗粒的平均尺寸，定性化学组成和数量密度均无显着变化，尽管辐照似乎会使较小的纳米颗粒略微变粗。两种材料均显示出非常小的（<2 nm）辐照引起的气泡，其尺寸相似，但ODS钢中的密度较低。正电子ni没光谱结果表明存在辐照引起的开放体积缺陷，在模型合金中更为明显。在两种合金中⁺照射。