Physicochemical properties of Al2O3 powder produced by explosive synthesis

Explosive compaction and low-temperature sintering of alumina nanopowders

“…This fact can be explained as follows. The phase composition of the initial powder is presented by (δ + θ)-modifications of Al 2 O 3 whose stabilization during the synthesis is performed due to embedding of a small number of nitrogen admixture atoms into the crystal lattice of alumina [22,25]. Explosive compaction involves partial stabilization of the material in the α-Al 2 O 3 phase, which is confirmed by results of the X-ray phase analysis (see below).…”

“…The powders had a white color, the particles had a spherical shape, the particle-size distribution was logarithmically normal, the mean numerical particle size was d 0.5 = 0.077 μm, and the dispersion was 1.68. The properties of these powders were studied in detail in [21,22]. As the reference substance, we used a P172SB submicron powder of alumina (d 0.5 = 0.5 μm) produced by the "Pechiney" company in France.…”

Detonation Synthesis of Ultrafine Alumina

“…Bukaemskii et al [5] reported the particle size distribution for one of the synthesized powder samples, which had three maxima corresponding to ultrafine spherical particles with a number-average size of 70 nm; dense, near-spherical particles ranging in size from 1 to 50 µ m; and a coarser fraction consisting of cellular aggregates, hollow spherical particles, and their fragments. The polydispersivity of the powder was interpreted under the assumption that aluminum combustion may occur in different regimes.…”

“…Detonation synthesis is carried out in a hermetically sealed chamber filled with oxygen-containing gases (initial pressure p 0 ). The explosive is placed in the center of a cardboard assembly consisting of two coaxial cylinders and is surrounded by a layer of PAP-1 aluminum powder (flaky particles with average dimensions of 10.6 × 7.2 × 1 µ m and volume-average size of 4.3 µ m [5]). Explosion is initiated from the upper face of the cylinder [3,6].…”

“…Detonation synthesis and properties of ultrafine alumina have been the subject of extensive studies [1,[3][4][5][6][7][8][9][10]. Detonation synthesis is carried out in a hermetically sealed chamber filled with oxygen-containing gases (initial pressure p 0 ).…”