Diamond-Silicon Carbide Composite And Method For Preparation Thereof

Patent · 06 September 2005

OSTI ID:880042

Qian, Jiang ^[1]; Zhao, Yusheng ^[1]

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1. Los Alamos, NM

Fully dense, diamond-silicon carbide composites are prepared from ball-milled microcrystalline diamond/amorphous silicon powder mixture. The ball-milled powder is sintered (P=5-8 GPa, T=1400K-2300K) to form composites having high fracture toughness. A composite made at 5 GPa/1673K had a measured fracture toughness of 12 MPa.multidot.m.sup.1/2. By contrast, liquid infiltration of silicon into diamond powder at 5 GPa/1673K produces a composite with higher hardness but lower fracture toughness. X-ray diffraction patterns and Raman spectra indicate that amorphous silicon is partially transformed into nanocrystalline silicon at 5 GPa/873K, and nanocrystalline silicon carbide forms at higher temperatures.

• Research Organization: Los Alamos National Laboratory
• DOE Contract Number: W-7405-ENG-36
• Assignee: The Regents of the University of California (Los Alamos, NM)
• Patent Number(s): US 6939506
• Application Number: 10/448672
• OSTI ID: 880042
• Country of Publication: United States
• Language: English