Synthesis and microstructure evolution of β-Sialon fibers/barium aluminosilicate (BAS) glass-ceramic matrix composite with enhanced mechanical properties

Dense Sialon fibers/barium aluminosilicate (BAS) matrix self-reinforced composite was synthesized by one-step method without applying pressure before or during sintering process. In this work, BAS matrix and internal Sialon fibers were synthesized successfully by directly sintering precursor powders at 1400 degrees C for 4 h. The BAS is not only introduced as a structural matrix material, but also as an effective liquid phase sintering aid to attain full densification bulk sample. The results show that the diameter of fibers is about 100-200 nm, and the quantity of the fibers can be changed with different temperatures. The obtained Sialon fibers/BAS matrix composites exhibit better toughness due to fiber bridging, crack deflection, and pullout. The sample with 3.5 wt% carbon content has maximum value of flexural strength (74.5 +/- 3.5 MPa) and fracture toughness (3.2 +/- 0.20 MPa center dot m(1/2)). The growth of the Sialon fibers follows a vapor-liquid-solid (V-L-S) mechanism. These findings featured with a green and simple preparation process provide a facile strategy to design and fabricate the bulk ceramic matrix composites in complex shapes and different sizes.

Automated summary

The study synthesized dense Sialon fibers/barium aluminosilicate (BAS) matrix self-reinforced composite using a one-step method, resulting in a material with high toughness and flexural strength. The quantity and diameter of fibers can be adjusted by changing the temperature. The green and simple preparation process offers a convenient strategy for designing and fabricating ceramic matrix composites in complex shapes and sizes.