Residual microstructure associated with impact craters in TiB2/2024Al composite
1School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Micron (Oxford, England : 1993)
|October 25, 2011
Summary
Hypervelocity impacts on titanium diboride/aluminum composites create new aluminum oxide phases and alter microstructures. These changes include stacking faults in titanium diboride particles and nanograin formation in the aluminum matrix.
Area of Science:
- Materials Science
- Nanotechnology
- Composite Materials
Background:
- Titanium diboride/aluminum (TiB(2)/Al) composites are advanced materials.
- Understanding their response to extreme conditions like hypervelocity impacts is crucial for applications.
Purpose of the Study:
- To investigate the residual microstructures in TiB(2)/Al composites after hypervelocity impact.
- To analyze the effects of impact on the TiB(2)-Al interface, TiB(2) particles, and Al matrix.
Main Methods:
- Transmission Electron Microscopy (TEM)
- High-Resolution Transmission Electron Microscopy (HRTEM)
Main Results:
- A novel Al(x)O(1-x) phase with face-centered cubic (fcc) structure was identified at the TiB(2)-Al interface.
- Stacking faults (10-20 nm width) formed on the (001) plane of TiB(2) particles.
- Nanograins (approximately 100 nm) formed in the Al matrix, and the S' phase transformed into S phase.
Conclusions:
- Hypervelocity impacts induce significant microstructural modifications in TiB(2)/Al composites.
- The formation of new phases and structural defects highlights the material's dynamic response to impact events.
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