Facile fabrication of lightweight hollow core-shell SiC@SiO2 fibers for high-temperature thermal insulation

Abstract

The development of new multi-functional high-temperature insulation materials is of crucial significance for promoting energy conservation and emission reduction and improving energy utilization efficiency. Silicon carbide (SiC) materials possess good thermal and chemical stability and are promising high-temperature insulation materials. However, the thermal and mechanical properties of intrinsic SiC materials must be further improved to fulfil the practical requirements. Microstructure control and component optimization are the main strategies for enhancing the thermal and mechanical properties of SiC materials. Therefore, studies for simultaneously synergizing the structure control and component optimization and simplifying the preparation process are of considerable significance. In this study, hollow core–shell SiC@SiO₂ fibers (HCSFs) were prepared via simple chemical vapour infiltration and high-temperature heat treatment, which enabled the facile construction of multiple structures and dual components. The HCSFs exhibit a light weight (36 mg/cm³), low thermal conductivity (0.032 W/(m·K)) and high operating temperature (1000 °C) as well as good mechanical properties (flexibility and tensile strength).