The toughening mechanism and mechanical properties of graphene-reinforced zirconia ceramics by microwave sintering

ABSTRACT

The graphene/ZrO₂ composites were fabricated by impregnating graphene dispersion into the ZrO₂ ceramic matrix and sintered by microwave, and the microstructure and mechanical properties were investigated. The results showed that the graphene was well dispersed in the ceramic matrix and refined the grain size. The fracture toughness reached 8.62 MPa m^1/2, confirmed by single-edge notched beam, which was 42% higher than that of the pure ZrO₂. Also, the toughening mechanisms were investigated by micro-hardness testing and showed that a combination of crack deflection, micro-crack and crack bridging increased the fracture toughness.

KEYWORDS:

• Graphene
• zirconia
• microwave sintering
• mechanical properties
• composites

Acknowledgments

We thank Mr Wanhong Tian for sintering the samples and Mr Bo Lu for testing Raman spectroscopy of the graphene/ZrO₂ samples.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Shanghai Chigong Ceramic Technology & Science Co., LTD [No. D.71-0100-16-027].