Lightweight and Strong Ceramic Network with Exceptional Damage Tolerance

Lightweight materials such as porous ceramics have attracted increasing attention for applications in energy conservation, aerospace and automobile industries. However, porous ceramics are usually weak and brittle; in particular, tiny defects could cause catastrophic failure, which affects their reliability and limits the potential use greatly. Here we report a SiC/SiO2 nanowire network constructed from numerous well-bonded SiC nanowires coated by a biphasic structure consisting of amorphous SiO2 and nanocrystal SiC. The as-obtained SiC/ SiO2 nanowire network is lightweight (360 +/- 10 mg cm-3), mechanically strong (compressive strength of 16 MPa), and damage-tolerant. The high strength of the network is attributed to the biphasic mixed structure of the binding coating which can restrict the deformation of nanowires upon compression. The lightweight and strong SiC/SiO2 nanowire network shows potential for engineering applications in harsh environments.

Automated summary

Lightweight porous ceramics have gained attention for their potential applications in energy conservation, aerospace, and automobile industries. However, their weakness and brittleness pose challenges, as tiny defects can lead to catastrophic failure and limit their reliability. In this study, we present a SiC/SiO2 nanowire network with a biphasic structure that exhibits lightweight properties, high mechanical strength, and damage tolerance. The network's strength is attributed to the mixed structure of the binding coating, which restricts nanowire deformation under compression. This lightweight and strong SiC/SiO2 nanowire network holds promise for engineering applications in harsh environments.