Mullite composite ceramics are promising materials for modern high-temperature metallurgical applications owing to their high density, elevated melting point, and minimum thermal expansion coefficient. However, their practical utility is often limited by insufficient high-temperature strength and inadequate thermal shock resistance. To address these issues, this study fabricates mullite composite ceramics with varying nano-ZrO 2 contents using a ceramics method, aiming to elucidate the role of nano-ZrO 2 in promoting the tailoring of microstructural architecture, as well as the underlying mechanisms governing high-temperature performance. The results indicate that the nano-ZrO 2 promotes the formation of a plate-like calcium hexaluminate (CA 6 ) network with a high aspect ratio through heterogeneous nucleation with solute-driven growth, and the median pore diameter decreasing from 7.91 μm to 2.83 μm and the pore volume distribution in the 2–15 μm from 5.37 to 177.16 µm 3 to 5.45–32.67 µm 3 . Consequently, the evolution the hot modulus of rupture (HMOR) and the residual cold modulus of rupture (CMOR) after thermal shock increase by 95.0% and 62.1%, respectively, while the slag erosion resistance index decreases by 48.8%. The properties enhancement of ceramics can be due to the formation of plate-like CA 6 network with a high aspect ratio and the pore structure This work provides a technologically viable strategy for the development of advanced high-temperature ceramics with enhanced reliability and extended service life.
陈平安 et al. (Sat,) studied this question.