Fabrication of high-performance Al 2 O 3 -ZrO 2 composite by a novel approach that integrates stereolithography-based 3D printing and liquid precursor infiltration

Abstract In this research, we creatively integrate the traditional methods of liquid precursor infiltration plus in-situ precipitation with stereolithography-based 3D printing for the fabrication of Al 2 O 3 -ZrO 2 ceramics to ensure the homogeneous distribution of ZrO 2 particle in the alumina matrix. Our characterization results shows that this combination leads to the materials with significantly better performance. The Al 2 O 3 specimen is soaked in a Zr 4+ ion solution to induce infiltration, in-situ precipitation and then sintered. X-ray diffraction analysis of the thus-treated sample indicated that Al 2 O 3 was the primary phase and t-ZrO 2 was the secondary phase. Microstructural and EDS analysis showed that the ZrO 2 particles were homogeneously distributed in the Al 2 O 3 matrix, leading to inhibited grain growth. The samples soaked in solutions for different Zr 4+ concentrations and sintered both at 1450 °C and 1550 °C showed improved mechanical properties as compared to those of pure alumina. Futhermore, the sample infiltrated using the solution with a concentration of 1.5 mol/L and sintered at 1450 °C showed similar fracture toughness (4.97 MPa m 1/2 ) with the sample sintered at 1550 °C (5.06 MPa m 1/2 ) but much better hardness (20.95 Gpa) than the sample sintered at 1550 °C (19.71 GPa). Therefore, this method could not only enhance the mechanical properties via introducing the second phase, but also lowers the sintering temperature by at least 100 °C, which would be beneficial for energy conservation and leads to significant advances in the 3D printing of ceramic components.