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Poor antioxidant and thermal-shock capacities of C/C composites thermal barrier coating (TBC) caused by cracking and shedding of coatings has been a major obstacle blocking the development of C/C composites. Herein, in-situ growth of whisker reinforced silicon carbide transition layer and inter-embedding mechanism of multi-gradient coatings were brought into the design of TBC to enhance the antioxidant and thermal-shock capacities. A three-layer gradient coating SiC-SiCw/ZrB2-SiC/ZrSiO4-aluminosilicate glass (ZAG) from inside to outside, in which ZrB2-SiC/ZAG serve as oxygen barrier layers with self-healing ability and SiC-SiCw provides thermal stress buffering and bonding against cracking and shedding of coatings, is designed. The ZAG mainly forms a dense oxygen blocking frontier with self-healing ability through fluidized glass, while the ZrB2-SiC can react actively with infiltrated oxygen in a way of self-sacrifice, preventing oxygen erosion to C/C matrix and SiC-SiCw transition layer. As a result, the collaborative work among layers endows this coating with excellent high temperature service performance. This work provides a new insight for the design of excellent TBC.

Herein, electron beam irradiation (EBI) was employed to in situ construct Ag-based micro/nanostructures. The composition of AgX@Ag (X = Cl−, Br−, etc.) composites and the size/morphology of silver nanoparticles (Ag-NPs) were tuned by adjusting the electron beam current density (EBCD) and the feeding dose of electrons. A hypothesis of gas–solid fluid-bed composed of atomic gas and nanocrystals is suggested to discuss the nanoparticle constructions with EBI. The low/medium EBCD creates a fixed fluid-bed for AgX@Ag-NPs and piled-pore architecture of Ag-NPs (PPAAg-NPs), while a high EBCD sets up a stirred fluid-bed for monodispersed Ag-NPs. Hopefully, this strategy would promote nanotechnology.