快堆属于第四代先进核反应堆，其燃耗将提升至200GWd/tU左右，因此堆内包壳将面临更加苛刻的高温和高剂量快中子辐照工作环境。15-15Ti奥氏体不锈钢因具有优良的高温蠕变抗性和良好的抗辐照及抗腐蚀性能，成为了快堆包壳的首选材料。在辐照环境中，材料会发生肿胀、相变和硬化等现象，其耐蚀性也会发生改变，性能下降，进而影响到反应堆的运行安全。本研究利用蒙卡程序模拟的方法对辐照过程进行了预测和分析，并采用能量为300keV的Xe离子和Fe离子分别对两种国产15-15Ti奥氏体不锈钢CN-15-15Ti-1和CN-15-15Ti-2进行了辐照实验，并通过扫描电镜、X射线衍射、纳米压痕和极化曲线等实验方法对样品辐照前后的表面形貌、微观结构、力学性能以及耐蚀性等进行了研究、比较和评价。模拟计算结果表明，入射离子能量较低时，辐照过程的能量损失以核碰撞为主。样品的辐照损伤值随辐照剂量的增加而增大，Xe离子辐照产生的损伤峰值更大，同时Fe离子辐照产生的损伤分布更深。另外，入射离子在材料内分布的峰值比辐照损伤分布的峰值更深。实验研究表明，样品的表面形貌在辐照前后没有出现SEM可观察到的明显变化。样品表面只有单一的奥氏体结构，Xe离子和Fe离子辐照都没有使样品产生新的相结构。Xe离子辐照后，样品表面的晶格常数随辐照剂量增加而变大，其中CN-15-15Ti-1样品的现象更明显。Fe离子辐照后，样品晶粒尺寸相比辐照前略有增大，但辐照剂量增加对其影响不明显。样品表面的微观硬度随着辐照剂量增加而增长，在相同辐照剂量条件下，Xe离子辐照对材料表面硬化的影响比Fe离子大。CN-15-15Ti-1样品的在辐照后硬度平均值更大，而CN-15-15Ti-2样品的硬化现象在高剂量辐照条件下更显著。离子辐照对样品的耐蚀性具有双重影响，因此样品的腐蚀性能变化并不是单调的。整体而言，样品在辐照后耐蚀性会有所下降，但仍可认为两种样品具有较好的耐蚀性。

Fast reactor is one of the Generation IV reactors, whose target burnup is expected to achieve approximately 200GWd/tU. Therefore, fuel claddings suffer from even severer conditions, that is, higher temperature and larger dose of fast neutron radiation. 15-15Ti austenitic stainless steels are considered recently as candidate structural materials for fuel claddings in fast reactors, owing to their high temperature strength capability coupled with reasonable radiation resistance. Under irradiation condition, materials are prone to swelling, phase transformation, hardening as well as altered corrosion resistance. These deteriorated properties thereby affect the safety of nuclear reactors. The work is aimed to evaluate the radiation properties of two kinds of domestic austenitic stainless steel, CN-15-15Ti-1 and CN-15-15Ti-2. The damage profiles and other statistics were calculated and predicted using one Monte Carlo program. Microstructural evolution and changes to the mechanical properties were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and nano-indentation after 300kev Xe-ion and Fe-ion beam respective irradiation at room temperature.According to the calculation results, when the ion energy is low, the energy loss is dominated by nuclear collision during the irradiation process. And the displacement damage grows with the increasing of ion dose. The maximum damage induced by Xe-ion beam is larger, while the depth of damage induced by Fe-ion beam is deeper. The surface of both CN-15-15Ti-1 and CN-15-15Ti-2 specimen changed little after ion irradiation. XRD analysis revealed that the specimen remained the austenitic microstructure and underwent no obvious phase transformation due to ion irradiation. The lattice parameter values increased gradually leading to the lattice distortion after Xe-ion irradiation, which happened to CN-15-15Ti-1 specimen more significantly. And the grain size grew slightly after Fe-ion irradiation, though irrelevant to the ion dose.Moreover, nano-indentation results indicated clearly that the hardness increments of the irradiated specimen compared to that of the unirradiated specimen. Xe-ion irradiation contributed to hardening more greatly than Fe-ion did. The average hardness of CN-15-15Ti-1 specimen after irradiation was even larger while that of CN-15-15Ti-2 specimen increased more sharply under high dose. The microstructural evolution can be responsible for the hardening after ion irradiation. Ion irradiation has a two-sided effect on the corrosion resistance of the specimen, therefore, the corrosion resistance changes corresponding to the two reversed effects. Overall, the corrosion resistance of the specimen decreased after both ions irradiation. Generally, the corrosion resistance keeps good for both kinds of 15-15Ti austenitic stainless steels.