Spherical boron nitride particles and method for preparing them

Patent · Tue Nov 25 04:00:00 EST 2003

OSTI ID:1174595

Phillips, Jonathan; Gleiman, Seth S.; Chen, Chun-Ku

Spherical and polyhedral particles of boron nitride and method of preparing them. Spherical and polyhedral particles of boron nitride are produced from precursor particles of hexagonal phase boron nitride suspended in an aerosol gas. The aerosol is directed to a microwave plasma torch. The torch generates plasma at atmospheric pressure that includes nitrogen atoms. The presence of nitrogen atoms is critical in allowing boron nitride to melt at atmospheric pressure while avoiding or at least minimizing decomposition. The plasma includes a plasma hot zone, which is a portion of the plasma that has a temperature sufficiently high to melt hexagonal phase boron nitride. In the hot zone, the precursor particles melt to form molten particles that acquire spherical and polyhedral shapes. These molten particles exit the hot zone, cool, and solidify to form solid particles of boron nitride with spherical and polyhedral shapes. The molten particles can also collide and join to form larger molten particles that lead to larger spherical and polyhedral particles.

• Research Organization: The Regents of the University of California, Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-36
• Assignee: The Regents of the University of California (Los Alamos, NM)
• Patent Number(s): 6,652,822
• Application Number: 09/860,016
• OSTI ID: 1174595
• Country of Publication: United States
• Language: English

Related Subjects

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