White fused alumina: high hardness and transparence

White fused alumina is an industrial product. It is melted of high qualitiy aluminium oxide in an electric arc. White fused alumina consists of about 99 % α-aluminium oxide. The outstanding property of white fused alumina is a high hardness and transparency. Only diamonds are tougher. This high hardness is a challenge for every grinding technology. Our micronized white fused alumina flours SEPASIL are characterized by a narrow grain size distribution. Another refining step is the surface-treatment with silanes or silane-based substances which can be adjusted to the respective application.



• depending on processing: the grain shape is round or splintered
• high hardness of 9 (Mohs)
• density of 3.95 g/cm³
• chemically inert
• high chemical resistance
• narrow grain size distribution
• transparent performance in many binding systems

Key applications

• abrasion-resistant wood and decorative coatings
• laminates
• casting resin systems and high voltage isolators

High performance fillers based on white fused alumina: