In the present study, Fe–9Cr model alloys were irradiated by 275 keV He⁺ ions at 500 to 800 °C to a peak damage level and implanted helium content of 0.5 dpa and 0.75 at% He, respectively. Effects of temperature on He bubble behaviour were studied by transmission electron microscopy (TEM) to reveal the temperature effects. The bubble spatial distribution changes from homogenous at 500 and 600 °C to heterogeneous at 700 and 800 °C, due to preferential bubble precipitation on dislocations and grain boundaries at high temperature. Faceted bubbles with low energy faces along the {001} planes were present at all four temperatures and are attributed to surface energy minimization. Bubble precipitation on the GBs became more pronounced with increasing temperature. Meanwhile, the cavity swelling increased with increasing temperature, from 0.59% at 500 °C to 8.21% at 800 °C with a sharp increase above 700 °C. By analysing the temperature dependence of bubble size and density, a transition temperature between low and high temperature regimes was obtained in terms of different activation energies which are related to different bubble nucleation and formation mechanisms.

在本研究中，Fe–9Cr模型合金被275 keV He ⁺辐照。离子在500至800°C时达到最高损伤水平，并且注入的氦含量分别为0.5 dpa和0.75 at％He。通过透射电子显微镜（TEM）研究了温度对He气泡行为的影响，以揭示温度的影响。由于高温下位错和晶界上的优先气泡沉淀，气泡的空间分布从500和600°C的均匀分布变为700和800°C的非均匀分布。在所有四个温度下均存在沿{001}平面具有低能级面的多面气泡，这归因于表面能的最小化。随着温度升高，GB上的气泡沉淀变得更加明显。同时，空腔膨胀随着温度的升高而增加，从500°C的0.59％增至800°C的8.21％，高于700°C时急剧增加。