Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms
In this study, we propose a novel approach to increase the fracture toughness of Al2O3 ceramics by incorporating core–shell structural composite whiskers as secondary phases. In particular, Al2O3 composite ceramics reinforced with TiC-coated SiC whiskers (SiCw@TiC) were successfully fabricated throu...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
| Language: | English |
| Published: |
Sciopen
2025
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| Online Access: | https://www.sciopen.com/article/10.26599/JAC.2025.9221093 http://hdl.handle.net/20.500.11937/98024 |
| _version_ | 1848766350126743552 |
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| author | Li, W. Pang, H. Zhang, Z. Cheng, L. Wang, Y. Zhang, X. Mu, J. Dong, Yu Wang, Y. Zhang, X. |
| author_facet | Li, W. Pang, H. Zhang, Z. Cheng, L. Wang, Y. Zhang, X. Mu, J. Dong, Yu Wang, Y. Zhang, X. |
| author_sort | Li, W. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | In this study, we propose a novel approach to increase the fracture toughness of Al2O3 ceramics by incorporating core–shell structural composite whiskers as secondary phases. In particular, Al2O3 composite ceramics reinforced with TiC-coated SiC whiskers (SiCw@TiC) were successfully fabricated through a combination of molten salt synthesis and spark plasma sintering (SPS). The SiCw@TiC whiskers feature a SiCw core and a TiC shell layer (~85 nm thick) composed of nano-sized TiC grains. Remarkably, the core–shell structure is preserved within the Al2O3 matrix after sintering, forming a unique composite toughening phase. The interfacial regions surrounding the whiskers exhibit a complex geometric configuration and multi-dimensional heterogeneities, including variations in phase composition (Al2O3/SiC/TiC), grain size (micron-/nano-scale), and thermal expansion coefficient (3.8×10−6–7.4×10−6/K), which collectively generate a sophisticated stress field. This intricate microstructure enables the SiCw@TiC whiskers to dissipate crack propagation energy through multiple mechanisms, significantly improving the fracture toughness of the Al2O3 matrix. The resulting Al2O3–SiCw@TiC composite ceramics demonstrate exceptional mechanical properties, with a relative density of 99.16%±0.48%, Vickers hardness of 21.38±0.93 GPa, flexural strength of 693±49 MPa, and fracture toughness of 7.15±0.47 MPa·m1/2. This work establishes a paradigm for structural ceramic toughening through engineered core–shell architectures. |
| first_indexed | 2025-11-14T11:49:45Z |
| format | Journal Article |
| id | curtin-20.500.11937-98024 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:49:45Z |
| publishDate | 2025 |
| publisher | Sciopen |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-980242025-07-23T02:11:50Z Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms Li, W. Pang, H. Zhang, Z. Cheng, L. Wang, Y. Zhang, X. Mu, J. Dong, Yu Wang, Y. Zhang, X. Al2O3 composite ceramics TiC-coated SiC (SiCw@TiC) core−shell structural whiskers Molten salt synthesis Mechanical properties Toughening mechanism In this study, we propose a novel approach to increase the fracture toughness of Al2O3 ceramics by incorporating core–shell structural composite whiskers as secondary phases. In particular, Al2O3 composite ceramics reinforced with TiC-coated SiC whiskers (SiCw@TiC) were successfully fabricated through a combination of molten salt synthesis and spark plasma sintering (SPS). The SiCw@TiC whiskers feature a SiCw core and a TiC shell layer (~85 nm thick) composed of nano-sized TiC grains. Remarkably, the core–shell structure is preserved within the Al2O3 matrix after sintering, forming a unique composite toughening phase. The interfacial regions surrounding the whiskers exhibit a complex geometric configuration and multi-dimensional heterogeneities, including variations in phase composition (Al2O3/SiC/TiC), grain size (micron-/nano-scale), and thermal expansion coefficient (3.8×10−6–7.4×10−6/K), which collectively generate a sophisticated stress field. This intricate microstructure enables the SiCw@TiC whiskers to dissipate crack propagation energy through multiple mechanisms, significantly improving the fracture toughness of the Al2O3 matrix. The resulting Al2O3–SiCw@TiC composite ceramics demonstrate exceptional mechanical properties, with a relative density of 99.16%±0.48%, Vickers hardness of 21.38±0.93 GPa, flexural strength of 693±49 MPa, and fracture toughness of 7.15±0.47 MPa·m1/2. This work establishes a paradigm for structural ceramic toughening through engineered core–shell architectures. 2025 Journal Article http://hdl.handle.net/20.500.11937/98024 10.26599/JAC.2025.9221093 English https://www.sciopen.com/article/10.26599/JAC.2025.9221093 http://creativecommons.org/licenses/by/4.0/ Sciopen fulltext |
| spellingShingle | Al2O3 composite ceramics TiC-coated SiC (SiCw@TiC) core−shell structural whiskers Molten salt synthesis Mechanical properties Toughening mechanism Li, W. Pang, H. Zhang, Z. Cheng, L. Wang, Y. Zhang, X. Mu, J. Dong, Yu Wang, Y. Zhang, X. Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms |
| title | Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms |
| title_full | Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms |
| title_fullStr | Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms |
| title_full_unstemmed | Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms |
| title_short | Core–shell SiCw@TiC composite whisker-reinforced Al2O3 ceramics: Preparation, properties, and toughening mechanisms |
| title_sort | core–shell sicw@tic composite whisker-reinforced al2o3 ceramics: preparation, properties, and toughening mechanisms |
| topic | Al2O3 composite ceramics TiC-coated SiC (SiCw@TiC) core−shell structural whiskers Molten salt synthesis Mechanical properties Toughening mechanism |
| url | https://www.sciopen.com/article/10.26599/JAC.2025.9221093 http://hdl.handle.net/20.500.11937/98024 |