Fraunhofer Institute for Ceramic Technologies and Systems IKTSCosts and improves performance gelcasting is an approach of liquid shaping where a few percents of a polymerizeable binder are added to the ceramic slurry. If a high solid loading is achieved at a low viscosity of the slurry, geometrically stable bodies are obtained with low shrinkage by pressureless casting at room temperature, consolidation by polymerization (< 80°C) and drying.
Advantages
- Free shaping
- Casting with low shrinkage (-> "near net shaping") reduces costs compared with pressing/"green" finishing
- Advantageous application to advanced raw materials (< 0.2 µm) and to coarser powders
- Reduces required sintering temperatures (250 °C compared with uniaxial pressing of 0,2 µm Al2O3-powder) -> sintering fine-grained microstructures
- Extreme homogeneity of powder compaction and low frequency of flaws give doubled strength and Weibull modulus (> 30) of pressureless sintered bodies (without phase transformation/anisotropic grains)
 Improved strength by gelcasting (Al2O3) |
 Reduced sintering temperature of gelcast alumina |
Products and services offered
- Development of processing for advanced ceramic products (sizes < 1 mm through round 100 mm)
- Development of approaches that reduce the costs of ceramic manufacturing when inexpensive (coarser) powders are to be used
- Investigation of alternative binder approaches (-> patent situation, -> environment, -> industrial safety)