(a–d) SiC/SiC composite clads: (a,c) DEMO-NITE SiC/SiC fracture surface and tubes; (b,d) CEA “sandwich” SiC/SiC cross-section and tube. (e) STEM image of a (Zr,Ti)₂AlC MAX phase grain next to a ZrC “impurity” grain. The magnified inset is a STEM image of the (Zr,Ti)₂AlC/ZrC interface. (f) Neutron-irradiated Ti₃SiC₂ (∼735 °C, 3.4 dpa): defect-denuded zones are established next to grain boundaries (GBs) acting as potent defect “sinks”. The magnified inset shows more damage in the “impurity” TiC grain than in Ti₃SiC₂. (g) TEM images of a nano-impacted, ion-irradiated (150 dpa) Al₂O₃ coating: the crack-like features are filled with vitreous matter. (h) GESA Al surface-alloyed 316 L steel exposed to liquid LBE (10 000 h, 600 °C, C _O ≈ 10⁻⁶ mass%). (i) GESA surface modification by an intense pulsed electron beam: volumetric heating → formation of a melt layer → restructured surface layer. (j) TEM image of a Fe-20Cr-5Al-0.5Ti-0.5Y₂O₃ alloy with nano-sized dispersoids. (k) Fe-14Cr ODS tube produced by CEA.