Fabrication and Properties of Machinable AlN-BN Ceramic Nanocomposites
The AlN/h-BN nanocomposite powders were synthesized through the reaction of AlN powder, boric acid (H3BO3) and urea (CO(NH2)2) in a nitrogen atmosphere, and the machinable AlN/BN ceramic nanocomposite s were fabricated by hot-pressing in N2 atmosphere. The existing and distribution of h-BN phase are revealed by X-ray diffraction (XRD), TEM and SEM. For the existing of weak interface between h-BN and AlN grains, the machinability of AlN/BN composites is improved obviously. For the finer microstructures, the mechanical properties and the machinability of the composites with micrometer sized AlN coated with nano-sized BN are better than the AlN/h-BN composite of mechanical mixing type.
T. Ohji, T. Sekino and K. Niihara
H. Y. Jin, W. Wang, J. Q. Gao, G. J. Qiao, Z. H. Jin, "Fabrication and Properties of Machinable AlN-BN Ceramic Nanocomposites", Key Engineering Materials, Vols. 317-318, pp. 637-640, 2006