High-purity, fine-particle boron nitride powder synthesis at -75 to 750 degrees C.
Tuscaloosa, AL: U.S. Department of the Interior, Bureau of Mines, RI 9012, 1986 Jan; :1-9
Nonoxide ceramics with improved high-temperature properties could substitute for high-temperature alloys and reduce the nation's dependence on imports of Cr, CO, Ni, and Mn. To meet this objective, the Bureau of Mines conducted research to synthesize ultrafine reactive boron nitride (BN) powders. BN powders were prepared at temperatures ranging from -75 deg to 750 deg C. Low- temperature reactions (-75 deg to 200 deg C) between boron halides and N compounds led to formation of elemento-organic compounds that were thermally decomposed to ultrafine (approximately 100- to 150-a particle size) reactive BN powders. BN powders were also prepared through the reaction of a low-melting inorganic b compound (boric acid, borax) with an organic n compound (carbimide and thiocarbimide) in n2 and/or ammonia (NH3) atmospheres at temperatures between 500 deg and 750 deg C. This report is based upon work done under an agreement between the University of Alabama and the Bureau of Mines.
Powder-particles; Synthesis; Ceramics; Boron-nitrides
IH; Report of Investigations
NTIS Accession No.
Tuscaloosa, AL: U.S. Department of the Interior, Bureau of Mines, RI 9012