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Updated: May 21, 2025
13:58
Probing C84-embedded Si Substrate Using Scanning Probe Microscopy and Molecular Dynamics
Published on: September 28, 2016
11.7K
Strong and Tough Porous Silicon Carbide Ceramics
De Lu1, Lei Zhuang1, Yuhang Yang1
1State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
ACS Nano
|May 7, 2025
Summary
Researchers developed strong and tough porous silicon carbide (SiC) ceramics using cross-linked SiC nanowire networks. This innovative approach significantly enhances mechanical properties for demanding structural applications.
Area of Science:
- Materials Science
- Ceramic Engineering
Background:
- Porous silicon carbide (SiC) ceramics show potential for severe condition structural use.
- Limited mechanical strength and fracture toughness hinder their widespread application.
Purpose of the Study:
- To develop strong and tough porous SiC ceramics.
- To enhance mechanical performance through SiC nanowire reinforcement.
Main Methods:
- Utilized hot-pressing to increase SiC nanowire network cross-linking.
- Employed chemical vapor infiltration for pyrolytic carbon (PyC) nanolayer coating.
- Introduced a SiC matrix via precursor infiltration and pyrolysis.
Main Results:
- Achieved impressive mechanical properties at 43% porosity.
- Reported flexural strength of 187 MPa and compressive strength of 215 MPa.
- Demonstrated fracture toughness of 3.4 MPa·m1/2 and energy absorption of 19.2 MJ·m-3.
Conclusions:
- Highly cross-linked SiC nanowire networks enhance strength and toughness.
- Multiple strengthening and toughening mechanisms were facilitated by the nanowire networks.
- This strategy offers a versatile method for improving porous ceramic performance.
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