Preparation and Properties of SiC-W₂B₅/C Composites

Area of Science:

• Materials Science
• Composite Materials
• Ceramics

Background:

• Advanced composites require enhanced mechanical properties and thermal stability.
• Optimizing the interface and microstructure is crucial for improving composite performance.

Purpose of the Study:

• To develop a novel processing route for SiC-W₂B₅/C composites.
• To investigate the effect of SiC content on the microstructure and mechanical properties.
• To understand the sintering mechanism and its influence on interface bonding and graphitization.

Main Methods:

• Reaction hot-pressing was employed to synthesize SiC-W₂B₅/C composites.
• Systematic variation of SiC content (5 to 30 vol%) was performed.
• Mechanical properties (flexural strength, fracture toughness, Vickers hardness) and microstructure were characterized.

Main Results:

• Composite density increased from 96.1% to 99.2% with rising SiC content.
• Exceptional mechanical properties were achieved: flexural strength of 292.3 MPa, fracture toughness of 6.12 MPa·m^1/2, and hardness of 3.32 GPa for the W15S30 composite.
• A Si-B-C transition phase formed, enhancing interface bonding and promoting graphitization from 59.2% to 66.2%.

Conclusions:

• Reaction hot-pressing is an effective method for producing high-density SiC-W₂B₅/C composites.
• Increased SiC content significantly improves mechanical properties and graphitization degree.
• The formation of a Si-B-C transition phase plays a key role in enhancing interfacial bonding and material performance.