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Thermally driven grain coarsening is a commonly encountered issue in nanocrystalline ceramics, particularly in high‐temperature environments. The intergranular glass film (IGF) constitutes a crucial component of most ceramics and plays a pivotal role in the process of grain coarsening. In this study, it is proposed to impede grain coarsening by constructing a chemically complex IGF comprising multiple dopants with distinct ionic radii. Ternary dopants encompassing Al3+, Y3+, and La3+ ions are simultaneously incorporated into a ZrO2–SiO2 nanocomposite. To fabricate the nanocomposite, an amorphous precursor powder with uniformly dispersed dopants is prepared using a chemical coprecipitation method, followed by rapid hot pressing to obtain a dense bulk sample. The distribution behavior of ternary dopants at IGFs between adjacent ZrO2 nanocrystallites (NCs) is carefully examined. It is revealed that the ternary dopants coexist at the IGFs. Moreover, Si4+ ions exhibit preferential enrichment at the IGFs. Remarkably, the presence of chemically complex IGFs significantly enhances the resistance to grain coarsening in ZrO2 NCs up to 1000 °C. In these findings, valuable insights are offered for designing and fabricating nanocomposites with exceptional resistance against grain coarsening. [ABSTRACT FROM AUTHOR]

Ceramics can be traditionally classified as structural and functional ones. However, the miniaturization and multi‐functionalization of various devices require ceramics to have both structural and functional properties. In this work, we aimed to develop structure‐function integrated ZrO2–SiO2 nanocrystalline glass–ceramics (NCGCs) by in situ formation of homogenously distributed amorphous carbon. By reducing the calcination temperature of carbon‐containing powder, organic carbon groups were partially retained in the powder and they transformed to amorphous carbon in the sintered NCGCs. At micrometer scale, the carbon was homogenously distributed in the NCGCs, avoiding the commonly encountered agglomeration problem of carbon fillers. The effects of carbon on the microstructure, mechanical properties, wear resistance, and dielectric properties of the NCGCs were investigated. Results showed that the in situ formed amorphous carbon was homogenously distributed in the ZrO2 nanocrystallites. Meanwhile, the amorphous carbon strongly bonded with the ZrO2–SiO2 NCGCs. Only a small amount of carbon was combusted even after annealing at 1000°C for 3 h. The formation of amorphous carbon led to an improvement of nanohardness and wear resistance of the NCGCs, while slightly reducing Young's modulus and flexural strength. The electromagnetic wave transmission performances were improved due to the formation of amorphous carbon. The current study paves a new way for developing structure‐function integrated glass–ceramics through in situ formation of carbon. The prepared structure‐function integrated ZrO2–SiO2 NCGCs have great potential to be used as radome and antenna windows of aerospace aircrafts that work in harsh environment. [ABSTRACT FROM AUTHOR]