Zirconia Ceramics
Zirconia grinding media features high density (specific gravity of alumina beads: approx. 3.6 g/cm³; specific gravity of zirconia beads: approx. 6.0 g/cm³), high strength and toughness. Therefore, it delivers outstanding wear resistance and extremely high grinding efficiency while preventing material contamination. It is especially suitable for wet grinding and dispersion processes and has been widely adopted in industries including ceramics, magnetic materials, coatings, inks, pharmaceuticals and food. Typical applications include premium automotive paints, mobile phone coatings, inkjet inks and high-end cosmetics.
With its high specific gravity (alumina beads ~3.6 g/cm³, zirconia beads ~6.0 g/cm³), great toughness and excellent wear resistance, zirconia grinding beads have gradually become the most widely used grinding media on the market. In powder engineering, besides serving as grinding media, zirconia is also an important material for sand mill components. Sand mills are well-known equipment for grinding operations. A high-performance sand mill must offer high grinding efficiency, stable equipment performance and consistent product quality. To achieve these merits, its components need to meet two key requirements: first, good wear resistance, meaning low wear rate during grinding and no severe contamination to ground materials; second, sufficient hardness to guarantee high grinding efficiency.
Among ceramic components, zirconia has a broad scope of application and represents the most mature ceramic material for sand mill parts. Among the four well-established advanced ceramic materials: zirconia, alumina, silicon carbide and silicon nitride, zirconia possesses the best toughness. Its advantages are particularly prominent when used as rotors in high-speed rotating sand mills. During high-speed operation, the contact and abrasion between rotors and materials tend to generate cracks on ceramic parts, which may eventually lead to fracture. Only zirconia ceramics can provide the required toughness for such demanding working conditions. The adoption of zirconia ceramic rotors satisfies the production and application requirements of high-purity ultrafine powders free from ferromagnetic contamination.