Calcined aluminium oxide with different particle size and α-Al2O3 content
Alumina in abrasive and friction materials
- Alumina is used in the production of abrasives and friction materials due to the high hardness and strength of its crystals.
- Higher is the α-Al2O3 content and higher is the hardness and the effectiveness on friction.
- This effect increases with increasing particle size and angular shape but an excessive amount can negatively affect the wear, expecially of the disc.
- Fine particles help to polish and clean the metallic counterface enhancing wear and friction stability.
- In a friction material is very important to optimize the relative quantity of alumina grades in order to find the best compromise between high level of friction and low wear.