Copper-boron nitride interaction in hot-pressed ceramics

Abstract

Ceramics were prepared by hot pressing of chemical mixtures of turbostratic boron nitride with copper. A positive effect of copper on boron nitride crystallization and densification has been found. Preferred orientation of boron nitride grains has been revealed in such ceramics, being opposite to general experience: the c-axis of boron nitride crystallites was arranged preferably within a plane perpendicular to the direction of uniaxial pressure. Such an arrangement is interpreted as a result of the uniaxial compression of the boron nitride grains extensively growing within the c crystallographic axis.

The effect of transition metals on the structure of h-BN intercalation compounds

“…A variety of intercalation compounds of hexagonal boron nitride (h-BN), which contains non-metallic guest molecules, was reported extensively [1]. On the other hand, there are several papers about the intercalation compounds of h-BN with copper [2,3] and silver [4].…”

“…Two methods [3] were used to obtain Cu-h-BN composites. The first one includes mechanical mixing and heating of h-BN with copper powder, while the second consists of the chemical treatment of the mixtures of boric oxides, urea and copper nitrate.…”

Investigations on NiAl composites fabricated by matrix coated single crystalline Al2O3-fibers with and without hBN interlayer

“…The texture development in the hBN-interlayer was caused by the radial pressure that was exerted on the coated fibers during diffusion bonding [20]. Under radial pressure, the c-axis of hBN tended to preferably arrange parallel to the direction of the pressure [21], i.e., the basal Table 1; (c)(d)(e)(f) The element mapping in the marked region in (a) planes of hBN would preferably orient themselves parallel to the interface. A similar texture was also observed in a previous study [22].…”

Stability and electronic structure of potassium-intercalated hexagonal boron nitride from density functional calculations

“…11 In this case, the bottom of conduction band at the ⌫ point also possesses NFE character and is distributed in the interlayer spacing. Although experimental results indicate that some chemical elements are indeed intercalated into h-BN, [13][14][15] the fundamental properties of the compounds remain unclear. Based on the analogy with GICs, the hybrid structure of h-BN and atoms that are intercalated into the interlayer spacing may also exhibit interesting electronic properties because the lower unoccupied electronic structure of h-BN is similar to that of graphite.…”