Relationship between matrix porosity and flexural strength of short fiber reinforced all-oxide ceramic matrix composites

Title data

Wagner, Lukas ; Puchas, Georg ; Schafföner, Stefan:
Relationship between matrix porosity and flexural strength of short fiber reinforced all-oxide ceramic matrix composites.
In: Journal of the European Ceramic Society. Vol. 46 (2026) Issue 5 . - 118020.
ISSN 0955-2219
DOI: https://doi.org/10.1016/j.jeurceramsoc.2025.118020

Project information

Abstract in another language

This study analyzes the influence of porosity on Nextel™ 610/Al2O3-ZrO2 short-fiber-reinforced composites for the first time. Its goal was the comparison of a short-fiber-reinforced all-oxide ceramic matrix composite (SF-Ox/Ox) with a fabric-reinforced material. Since the matrix system and the processing were the same for both materials, differences can be related to the use of short-fibers instead of fabrics. Zirconium-n-butoxide was infiltrated to decrease the porosity from 46 % to 32 %, which increased the bending strength and the Young’s modulus from 85 ± 19 MPa to 120 ± 23 MPa and 40 ± 10 GPa to 82 ± 12 GPa, respectively. The strain decreased with decreasing porosity from 0.25 ± 0.05 % to 0.16 ± 0.03 %. The damage-tolerant behavior was maintained for all samples, which was never shown for SF-Ox/Ox in such a porosity range. The less anisotropic alignment of the short-fibers is therefore advantageous for crack-deflection. This offers the possibility to obtain damage-tolerance while having a denser matrix system.