|About this Abstract
||Materials Science & Technology 2020
||Processing and Performance of Materials Using Microwaves, Electric and Magnetic Fields, Ultrasound, Lasers, and Mechanical Work – Rustum Roy Symposium
||Deforming Polycrystalline Ceramics by Dislocation Based Plastic Deformation
||Lukas Porz, Michael Scherer, Wolfgang Rheinheimer, Atsutomo Nakamura, Jürgen Rödel
|On-Site Speaker (Planned)
Dislocation-based plastic deformation of polycrystalline ceramics, which is possible at high temperatures, both gives the opportunity to shape ceramics and to introduce dislocations to tune their functional properties. Deformation is, however, much less known for ceramic polycrystals than compared to single crystals. For many materials it is still unclear to which extent this is even possible.
Using polycrystalline SrTiO3 as model material, we demonstrate that deformation of several percent is achievable. By analyzing the samples and determining dislocation densities with high voltage electron microscopy, the process can be clearly linked to dislocation movement. A detailed discussion of the mechanical behavior at elevated temperature is presented including stress-strain curves at different temperatures and different strain rates. Hence, a parameter range in which plastic deformation is possible is benchmarked. Obtained dislocation densities are also discussed in the context of tuning functional properties such as electric and thermal conductivity.