We have monitored in situ the lattice defect evolution induced by proton irradiation in 20Cr-25Ni Nb-stabilised stainless steel, used as fuel cladding material in advanced gas-cooled reactors. At 420 °C, the damaged microstructure is mainly characterised by black spots and faulted $\frac{a_0}{3}〈111〉$ Frank loops. Defect saturation is reached at only 0.1dpa. In contrast, at 460 °C and 500 °C proton bombardment induces the formation of a mixture of $\frac{a_0}{3}〈111〉$ Frank loops and perfect $\frac{a_0}{2}〈110〉$ loops. These perfect loops evolve into dislocation lines that form a dense network. This transition coincides with the saturation in the dislocation loop size and number density at 0.8dpa (460 °C) and 0.2dpa (500 °C), respectively. The presence of a high density of dislocation loops and lines at those two temperatures causes a vacancy supersaturation in the matrix, leading to the formation of voids and stacking fault tetrahedra.

我们已经在20Cr-25Ni Nb稳定的不锈钢中用作质子辐照引起的晶格缺陷演变的原位监测，该不锈钢在先进的气冷反应堆中用作燃料包壳材料。在420°C时，损坏的微观结构主要表现为黑点和断层。$\frac{{\mathrm{一个}}_0}{3}〈111〉$弗兰克循环。缺陷饱和度仅为0.1dpa。相反，在460°C和500°C时，质子轰击会导致$\frac{{\mathrm{一个}}_0}{3}〈111〉$ 弗兰克循环和完美 $\frac{{\mathrm{一个}}_0}{\mathrm{2个}}〈110〉$循环。这些完美的循环演变成位错线，形成密集的网络。这种转变与位错环的大小和数密度的饱和相一致，分别为0.8dpa（460°C）和0.2dpa（500°C）。在这两个温度下高密度的位错环和位错的存在会导致基体中出现空位过饱和，从而导致形成空隙和堆积断层四面体。