Fabrication of Fine AlN Particles by Pulverizing with Very Small ZrO₂ Beads

Abstract

Nano‐sized aluminum nitride (AlN) powders can enhance the sinterability of AlN ceramics. The present work examined the pulverization and dispersion of AlN powder using ZrO2 beads of 0.1 mm in diameter as grinding medium in order to obtain nano‐sized powder for low‐temperature sintering. An attracting feature of the bead grinding is that the rotor creates centrifugal and shearing forces, which lead to efficient pulverization that exceeds the conventional grinding limit. The AlN powder with agglomerates and average particle size of 0.38 μm was broken up into more homogeneous particles with a narrow particle size distribution after 90 min of grinding. Qualitative examinations of the powder by transmission electron microscopy and BET indicated that the particle size was 50–100 nm and specific surface area was 70 m2/g.

Multi-layer electrode with nano-Li4Ti5O12 aggregates sandwiched between carbon nanotube and graphene networks for high power Li-ion batteries

“…The sequential steps include a series of (1) air-spray deposition of GNSs as an intermediate buffer layer on a stainless steel current collector and (2) electrostatic spraying of the colloidal nano-Li 4 Ti 5 O 12 powder pulverized by high energy micro-bead milling (Supplementary Fig. S1)38. The close-packed particle structure of the Li 4 Ti 5 O 12 aggregates was obtained through the evaporation of the ethanol solvent with a low boiling point (78.37°C) and the solidification after the fission droplet process as illustrated in the inset image (bottom right).…”

Enhancement of Densification and Thermal Conductivity in AlN Ceramics by Addition of Nano‐Sized Particles

“…A commercially available AlN raw powder (MAN‐2, O: 0.35 mass%; C: 0.04 mass%; specific surface area: 1.9 m 2 /g; primary particle size: 0.9 μm; Mitsui Chemicals, Tokyo, Japan) was used. The nano‐sized AlN powder was synthesized in a super‐fine grinding mill using ZrO 2 beads as the medium, 10 and its average particle size and specific surface area were <100 nm and 70 m 2 /g, respectively. The micrograph of the nano‐sized powders is shown in Fig.…”

“…and Panchula and Ying 9 demonstrated that the AlN ceramics could reach >98% of their theoretical densities by pressureless sintering at 1700°C using nano‐sized powders. Our earlier work showed that nano‐sized AlN powders, which were synthesized in a super‐fine grinding mill using ZrO 2 beads as milling medium from the as‐received AlN powders, 10 achieved a higher sinterability, 11,12 compared with the commercially available powders. In the present work, we substituted a certain fraction of the rare‐earth and/or alkaline‐earth oxides with nano‐sized AlN powders and investigated the effect of the nano‐sized powder on the densification and the thermal conductivity of the AlN ceramics sintered at a low temperature.…”

Effects of the processing parameters in the synthesis of BaTiO3 nanoparticle by using the co-precipitation method

“…Bead mills are known to be a useful way to grind and disperse agglomerates of ultra-fine or nano-sized particles. Several studies have reported that agglomerated ceramic powders can be well dispersed into nano-sized particles by bead milling [11][12][13].…”