Low-temperature and flexible strategy to in-situ fabricate ZrSiO₄-based ceramic composites via doping and tuning solid-state reaction

Synthetic zircon (ZrSiO₄) ceramics are typically fabricated at elevated temperatures (over 1500 ℃), which would lead to high manufacturing cost. Meanwhile, reports about preparing ZrSiO₄-based ceramic composites via controlling the solid-state reaction between zirconia (ZrO₂) and silica (SiO₂) are limited. In this work, we proposed a low-temperature strategy to flexibly design and fabricate ZrSiO₄-based ceramic composites via doping and tuning the solid-state reaction. Two ceramic composites and ZrSiO₄ ceramics were in-situ prepared by reactive fast hot pressing (FHP) at approximately 1250 ℃ based on the proposed strategy, i.e., a ZrSiO₄–SiO₂ dual-phase composite with bicontinuous interpenetrating and hierarchical microstructures, a ZrSiO₄–ZrO₂ dual-phase composite with a microstructure of ZrO₂ submicron- and nano-particles embedded in a micron ZrSiO₄ matrix, and ZrSiO₄ ceramics with a small amount of residual ZrO₂ nanoparticles. The results showed that the phase compositions, microstructure configurations, mechanical properties, and wear resistance of the materials can be flexibly regulated by the proposed strategy. Hence, ZrSiO₄-based ceramic composites with different properties can be easily fabricated based on different application scenarios. These findings would offer useful guidance for researchers to flexibly fabricate ZrSiO₄-based ceramic composites at low temperatures and tailor their microstructures and properties through doping and tuning the solid-state reaction.