The anisotropic hardening response in a 12Cr-ODS ferritic steel was investigated before and after irradiation with 2.8 MeV Fe²⁺ at room temperature up to displacement damages of 0.5 and 15 dpa. For post irradiation examination, techniques of nano-indentation and orientation imaging microscopy were jointly applied to link crystal orientation with nano-hardness. Results showed that the averaged hardness of normal direction-transverse direction (TD-ND) specimen is less than that of rolling direction-transverse direction (RD-TD) specimen irrespective of the dose of irradiation damage. However, the amount of irradiation-induced hardening is observed to be weaker in TD-ND specimen relative to RD-TD specimen. These anisotropic phenomena are considered to be mainly attributed to the elongated grain structure with a very high grain aspect ratio of the present steel, in which smaller-sized grains are exhibited in TD-ND plane nevertheless fairly coarse grains are in RD-TD plane. In addition, the orientation dependent hardness and irradiation-induced hardening were confirmed. Specifically, the hardness of [001]-oriented grain is lower than that of [111]-oriented grain with and without irradiation. With the presence of irradiation, it was found that the extent of hardening is more obvious at [001]-oriented grain than [111]-oriented grain, which is attributed to a more activated primary {110}<111> slip beneath the indenter when tested at [100]-oriented grain compared with [111]-oriented grain.

在2.8 MeV Fe ²⁺辐照之前和之后，研究了12Cr-ODS铁素体钢中的各向异性硬化响应。在室温下，位移损失为0.5和15 dpa。对于辐照后检查，纳米压痕和取向成像显微镜技术被联合应用以将晶体取向与纳米硬度联系起来。结果表明，与照射损伤的剂量无关，法向-横向（TD-ND）试样的平均硬度小于轧制-横向（RD-TD）试样的平均硬度。但是，相对于RD-TD样品，在TD-ND样品中观察到辐射诱导的硬化量较弱。这些各向异性现象被认为主要归因于本发明钢的具有非常高的晶粒纵横比的细长晶粒结构，其中较小尺寸的晶粒在TD-ND平面上显示，而相当粗大的晶粒在RD-TD平面上。另外，证实了取向依赖性硬度和辐射诱导的硬化。具体地，在有和没有辐照的情况下，[001]取向晶粒的硬度低于[111]取向晶粒的硬度。在存在辐射的情况下，发现在[001]取向的晶粒上的硬化程度比[111]取向的晶粒更明显，这归因于压头下方的主要{110} <111>滑移激活在[100]取向晶粒与[111]取向晶粒进行测试时。