Microstructure and Properties of Micro/Nano-Scale (TiB₂ + TiC)/Al Composites Prepared by Ti-B₄C Reactive Sintering...

Area of Science:

• Materials Science
• Metallurgy
• Nanotechnology

Background:

• Aluminum (Al) matrix composites offer tunable properties for various applications.
• Incorporating ceramic reinforcements like Titanium Diboride (TiB2) and Titanium Carbide (TiC) can significantly enhance mechanical performance.
• Fabrication methods influence microstructure and final composite properties.

Purpose of the Study:

• To fabricate micro/nano-scale (TiB2 + TiC)/Al composites.
• To investigate the effect of varying TiB2 and TiC reinforcement content (0-30 wt.%) on the microstructure and mechanical properties.
• To determine the optimal composite composition for enhanced strength, ductility, and wear resistance.

Main Methods:

• Reactive sintering of Ti-B4C powder mixtures.
• Spark Plasma Sintering (SPS) for consolidation.
• Microstructural analysis using techniques like SEM and TEM (implied).
• Mechanical testing including Vickers hardness, compressive strength, and wear tests.

Main Results:

• A complete reaction between Ti and B4C at 1400 °C produced bimodal TiB2-TiC reinforcements.
• Significant grain refinement of the Al matrix was observed with increasing reinforcement content.
• Vickers hardness and compressive yield strength increased with reinforcement content.
• Optimal properties were achieved at 20 wt.% (TiB2 + TiC)/Al composite, exhibiting high strength (914.6 MPa), ductility (~73.2%), and low wear rates.

Conclusions:

• The combination of reactive sintering and SPS is effective for producing high-performance (TiB2 + TiC)/Al composites.
• Micro/nano-scale TiB2 and TiC reinforcements enhance Al matrix properties through grain refinement, dispersion strengthening, and improved load-bearing capacity.
• The 20 wt.% composite demonstrates excellent comprehensive mechanical performance and wear resistance, making it suitable for demanding applications.