Perfect sub-µm micostructures reduce the wear of grinding balls in volume, particle size, and impurity content
Known grinding balls with low and sub-µm wear consist, e.g. of ZrO2 (detrimental in Al2O3 substrates for microelectronics or in alumina with high permeability for microwaves), balls of 85 % Al2O3 introduce silica impurities. Commercial high-purity Al2O3 grinding balls exhibit increased and coarser wear. The corundum balls developed here by IKTS Dresden avoid these disadvantages and enable highly pure ceramic processing for special use.
- Highest purity > 99.9 % α-Al2O3.
- Minimum wear (1/4 of the typical wear of 85 % Al2O3 balls) due to sub-µm grain size < 0.5 µm at high relative density > 99.9%.
- High hardness HV10 > 2000.
- Small average particle size of wear (0.6 µm).
- Use in fast attrition mills enabled by high specific fracture stress (750 – 1000 MPa in compression).
- License on know how. Upscaling. Contributions to the development of an industrial production of new grinding balls.
- Supply of new wear resistant corundum balls.
- Investigations of the performance in technical applications.
|Grade of grinding balls||Wear rate* [%/h]|
|New product from IKTS||0.025|
|commercial 85% Al2O3||0.09|
* Wear of new sub-µm alumina grinding balls in an attrition mill (water, 1000 rev/min) in comparison with commercial grades.