Novel water-based processing of graphene oxide and sub-micrometric alumina towards tougher and electrically-conductive structural ceramics
Balancing the mechanical and functional properties of graphene-reinforced ceramics can be a challenge because agglomeration of the reinforcement must be avoided to minimise microstructural defects and it is difficult to organise the constituents into meaningful structures. The water-based processing...
| Authors: | , , , , , , , , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2025 |
| Country: | España |
| Institution: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repository: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/391390 |
| Online Access: | http://hdl.handle.net/10261/391390 |
| Access Level: | Open access |
| Keyword: | Graphene Alumina Ceramic-based composites Freeze-casting Spark plasma sintering |
| Summary: | Balancing the mechanical and functional properties of graphene-reinforced ceramics can be a challenge because agglomeration of the reinforcement must be avoided to minimise microstructural defects and it is difficult to organise the constituents into meaningful structures. The water-based processing strategy that is demonstrated here illustrates the potential to fabricate layered alumina composites using a combination of freeze-casting, vacuum infiltration, and spark plasma sintering. Layers of alumina between 0.5 and 7 μm thick and consist of an average grain size of 0.7 ± 0.4 μm were separated by highly-oriented reduced graphene oxide. Mechanical and functional properties were investigated alongside a monolithic counterpart sintered at 1300 °C. The flexural strength and fracture toughness increased from 262 to 314 MPa and 3.5–5.4 MPa m1/2 respectively, whilst electrical conductivity rose by nine orders of magnitude to 10−1 S cm−1. |
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