Multi-directional freeze casting of porous ceramics with bone-inspired microstructure
Porous ceramics are favored in a multitude of applications, such as filters, catalyst supports, and tissue engineering scaffolds. However, conventional fabrication techniques find it particularly challenging to preserve sufficient mechanical strength in highly porous ceramics. Although unidirectiona...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2022-12-01
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| Series: | Materials & Design |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0264127522009662 |
| _version_ | 1828090245905645568 |
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| author | Xinyu Dong Beng Wah Chua Tao Li Wei Zhai |
| author_facet | Xinyu Dong Beng Wah Chua Tao Li Wei Zhai |
| author_sort | Xinyu Dong |
| collection | DOAJ |
| description | Porous ceramics are favored in a multitude of applications, such as filters, catalyst supports, and tissue engineering scaffolds. However, conventional fabrication techniques find it particularly challenging to preserve sufficient mechanical strength in highly porous ceramics. Although unidirectional freeze casting can fabricate porous ceramics with high strength vertically, the strength in other directions is inadequate due to a lack of lateral structural control. Herein, inspired by the cancellous bone, we propose a novel multi-directional freeze casting technique to prepare highly mechanically efficient porous ceramics. A multi-directional temperature field is ingeniously designed to mimic the stress-responsive growth pattern of the cancellous bone. To further the lateral structural control, ceramic fibers are incorporated to form mineral bridging. In this process, alumina-mullite composite ceramics are prepared with hierarchical structures, including micro-level multi-oriented struts, sub-micro-level interlamellar bridges and nano-level eutectic phases. They endow the ceramics with high porosity (∼75%) and high strength in all 3D spatial directions (8.4–20.1 MPa), while effectively preventing the catastrophic brittle failure. Therefore, the mechanically enhanced porous ceramics demonstrate the remarkable controllability of multi-directional freeze casting in hierarchical structures. Also, our work opens up a new horizon for fabricating highly mechanically efficient porous materials, including hierarchically structured biomimetic ceramics. |
| first_indexed | 2024-04-11T05:53:51Z |
| format | Article |
| id | doaj.art-021a078a5e1c4e9189348804656227c4 |
| institution | Directory Open Access Journal |
| issn | 0264-1275 |
| language | English |
| last_indexed | 2024-04-11T05:53:51Z |
| publishDate | 2022-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Materials & Design |
| spelling | doaj.art-021a078a5e1c4e9189348804656227c42022-12-22T04:41:57ZengElsevierMaterials & Design0264-12752022-12-01224111344Multi-directional freeze casting of porous ceramics with bone-inspired microstructureXinyu Dong0Beng Wah Chua1Tao Li2Wei Zhai3Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, 117575 Singapore, SingaporeSingapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A*STAR), 138634 Singapore, SingaporeSingapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A*STAR), 138634 Singapore, SingaporeDepartment of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, 117575 Singapore, Singapore; Corresponding author.Porous ceramics are favored in a multitude of applications, such as filters, catalyst supports, and tissue engineering scaffolds. However, conventional fabrication techniques find it particularly challenging to preserve sufficient mechanical strength in highly porous ceramics. Although unidirectional freeze casting can fabricate porous ceramics with high strength vertically, the strength in other directions is inadequate due to a lack of lateral structural control. Herein, inspired by the cancellous bone, we propose a novel multi-directional freeze casting technique to prepare highly mechanically efficient porous ceramics. A multi-directional temperature field is ingeniously designed to mimic the stress-responsive growth pattern of the cancellous bone. To further the lateral structural control, ceramic fibers are incorporated to form mineral bridging. In this process, alumina-mullite composite ceramics are prepared with hierarchical structures, including micro-level multi-oriented struts, sub-micro-level interlamellar bridges and nano-level eutectic phases. They endow the ceramics with high porosity (∼75%) and high strength in all 3D spatial directions (8.4–20.1 MPa), while effectively preventing the catastrophic brittle failure. Therefore, the mechanically enhanced porous ceramics demonstrate the remarkable controllability of multi-directional freeze casting in hierarchical structures. Also, our work opens up a new horizon for fabricating highly mechanically efficient porous materials, including hierarchically structured biomimetic ceramics.http://www.sciencedirect.com/science/article/pii/S0264127522009662Freeze castingBioinspired materialsPorous ceramicsMechanical properties |
| spellingShingle | Xinyu Dong Beng Wah Chua Tao Li Wei Zhai Multi-directional freeze casting of porous ceramics with bone-inspired microstructure Materials & Design Freeze casting Bioinspired materials Porous ceramics Mechanical properties |
| title | Multi-directional freeze casting of porous ceramics with bone-inspired microstructure |
| title_full | Multi-directional freeze casting of porous ceramics with bone-inspired microstructure |
| title_fullStr | Multi-directional freeze casting of porous ceramics with bone-inspired microstructure |
| title_full_unstemmed | Multi-directional freeze casting of porous ceramics with bone-inspired microstructure |
| title_short | Multi-directional freeze casting of porous ceramics with bone-inspired microstructure |
| title_sort | multi directional freeze casting of porous ceramics with bone inspired microstructure |
| topic | Freeze casting Bioinspired materials Porous ceramics Mechanical properties |
| url | http://www.sciencedirect.com/science/article/pii/S0264127522009662 |
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