Effects of n-Al2O3 and µ-TiCN on Microstructure and Mechanical Properties of Al2O3 Composite Ceramics Manufactured by Material Extrusion and Photo-Polymerization Combined Process

Abstract

Alumina (Al2O3) composite ceramics with different composition ratio and particle-size distribution were fabricated by the material extrusion and photo-polymerization combined process (MEX-PPM) based on additive-manufacturing (AM) technology in our previous work. These particles were nanosized Al2O3 (n-Al2O3), micron-sized TiCN (µ-TiCN) and Al2O3. Effects of n-Al2O3 and µ-TiCN on Al2O3 composite ceramics were investigated by characterizing the volume density, EDS spectrum, mechanical properties and microstructure of the prepared samples. It was found that n-Al2O3 had a significant effect on the hardness of Al2O3 composite ceramics, µ-TiCN, with excellent performance in density, flexural strength and fracture toughness. The Al2O3 composite ceramics with optimum contents of 10 wt % n-Al2O3 and 30 wt % µ-TiCN showed good microstructure and mechanical properties. Their porosity and volume density were at 4.073% and 4.177 g/cm3, respectively. Their hardness, flexural strength and fracture toughness were at 16.592 GPa, 592.875 MPa and 6.308 MPa/mm2. The flexural strength of the ceramics was significantly higher than that of Al2O3 ceramics prepared by SLA in document (178.84 ± 17.66 MPa), which had great potential in high-pressure strength structure.