![Submicrometer Aluminium oxide tool ceramic (average grain size 0.56 µm). schneidsubgr](/en/departments/structural_ceramics/nonoxide_ceramics/materials_synthesis_development/bearings_wear-resistant_components/jcr:content/contentPar/sectioncomponent/sectionParsys/textblockwithpics/imageComponent1/image.img.jpg/1565085030817/schneidsubgr-tcm185-32377.jpg)
![Decreasing the grain size gives pure, chemically and thermally stable α-Al2O3 (corundum) with a similarly high hardness as Al2O3/TiC composites. verschleißteile1](/en/departments/structural_ceramics/nonoxide_ceramics/materials_synthesis_development/bearings_wear-resistant_components/jcr:content/contentPar/sectioncomponent/sectionParsys/textblockwithpics/imageComponent2/image.img.jpg/1565085030817/verschleissteile1tcm185-37509.jpg)
![Minimum wear of new sub-µm corundum ceramics in different environments. verschleissteile2](/en/departments/structural_ceramics/nonoxide_ceramics/materials_synthesis_development/bearings_wear-resistant_components/jcr:content/contentPar/sectioncomponent/sectionParsys/textblockwithpics/imageComponent3/image.img.jpg/1565085030817/verschleissteile2tcm185-33014.jpg)
Sub-µm and nanotechnologies for components associating highest hardness and wear resistance with an extreme thermal and chemical stability
Known components made of hardmetals, Si3N4 or TiC-reinforced composites exhibit a limited stability in agressive environments because of metallic, glassy or oxidizing constituents, Zirconia ceramics are less hard and their microstructure and strength critically depend on the temperature. The new sub-µm corundum ceramics (Fig. 1) avoid these shortcomings, and their hardness surpasses all grades addressed above.
Advantages
- Extremely high hardness (Fig. 2)
- Significantly improved wear resistance (Fig. 3)
- Reduced aging in aqueous media compared with advanced commercial grades of sintered corundum (Fig. 4)
- High strength (600-850 MPa), nearly constant up to about 1000 °C
- High chemical stability in acids, bases, and agressive gases.
Subcritical crack velocity of sub-µm Al2O3 ceramics in water and in air compared with conventional grades: evidence of an outstanding high reliability of the new sub-µm ceramics in aqueous media.
Products and services offered
- Development of high-purity ceramics on the basis of corundum (α-Al2O3) with sub-µm/nano microstructures for wear resistant components
- Alternative development with commercial or with nanoscale raw materials
- Technological investigations for upscaling supporting the development of new products; screening of raw materials and shaping approaches
- Investigations of the technical performance in various applications