Preparation and characterization of high-strength and thermal shock resistance ZrO2-based ceramic scaffolds via material extrusion

In this study, a method for fabricating ZrO₂-based ceramic scaffolds via material extrusion technique was proposed. 3 mol% Y₂O₃ stabilized ZrO₂ is used as raw material and phenolic resin as the binder. Ceramic scaffolds were fabricated by systematically regulating the rheological properties of ceramic slurry and printing parameters. By collaboratively optimizing the sintering process parameters, the microstructure of the ceramic scaffold was significantly refined and the mechanical properties were greatly improved. The results show that when the filling rate is 50 % and the sintering temperature is 1400 °C, the ceramic scaffold exhibits excellent comprehensive performance: the bulk density reaches 1.25 g·cm⁻³ and the bending strength is 136.45 MPa. In addition, this ceramic scaffold exhibits remarkable thermal shock stability. The residual bending strength ratio typically exceeded 80% after thermal shock testing. It is noteworthy that a distinct whisker-like structure was observed on the sample surface after thermal shock. This study provides theoretical support and technical reserves for the application of high-performance ceramic scaffolds in high-temperature extreme environments such as aerospace.