Aluminium Oxide, calcined & fused

We offer both calcined as well as fused Aluminium Oxides (Al₂O₃).

Calcined Aluminium Oxides are among the most commonly used abrasives in the friction materials industry and come in two varieties, alpha and gamma oxides. 

While alpha oxides have a high hardness of 8-9 Mohs they are still not overly aggressive towards the brake disc unless a high-calcined grade is chosen. In general, the higher the grade of calcination, the harder and more crystal-like the material.

Gamma oxides on the other hand have a lower hardness of 6-7 Mohs and tend to be less used, mostly for special applications in NAO type friction-formulations only.

We also carry a variety of special grades with very fine particle sizes that have shown to lower disc wear while maintaining friction level, such as NO265. This grade is also recommended to solve metal pick up issues.

Fused Aluminium Oxides, sometimes also referred to as corundum, are widely used raw materials in the abrasives and refractories industry.

Depending on the mix ratio of the base materials, the resulting material is referred to as brown or white fused alumina because of the respective colour.

Its main properties are a high hardness of typically 9 Mohs as well as abrasiveness and temperature stability. It is more often used in heavy duty friction applications where a high load friction coefficient is the major concern.