Extended Data Fig. 9: Mechanical properties, STEM characterizations and dynamic evolution of NPs of the superlattice steels with different Al contents and density of NPs.
a, Nanoindentation hardness evolution of the superlattice steels with different density of NPs as a function of radiation damage at 500 °C. The value without NPs is plotted by yellow dashed line and the line width indicates the corresponding error bar. Detailed description of the NPs in the superlattice steels with different NP density is provided in Supplementary Table S3. b, Nanoindentation hardness evolution of the superlattice steels and solution-annealed steel subjected to ion irradiation at 500 °C. c-e, STEM characterization of the 2Al superlattice steel with lower NPs density before and after ion irradiation; c, As-prepared. d, 84 dpa, 500 °C. e, 840 dpa, 500 °C. No NPs were observed in the ion-irradiated samples. f, Atomic resolved cross-sectional HAADF-STEM image of the steel with low NP density (that is, the 2Al steel) after 840 dpa ion irradiation at 500 °C. The inset is the corresponding FFT image showing weak spots of B2 structure. g, Inverse FFT image showing the B2 reordered regions (several are circled). h, Vickers hardness versus aging time revealing nanoprecipitation kinetics of the superlattice steels with different Al contents.The error bars are the standard deviation of the mean.
