Functional Ceramics – Future Strategies for Modifying Properties and Enabling Fast Sintering

The functional properties of ceramics are usually tailored by designing point defects and interfaces. Dislocations as heavily charged nanoscale one-dimensional line defects are so far underrepresented means to tune functionality. However, the opportunity to tune ceramics beyond what can be achieved by chemical doping is of significant interest. Mechanically introduced dislocations possess the ability to modify the functional properties extensively. For example, the conductivity of electronic and ionic oxide ceramic conductors can be enhanced by multiple orders of magnitude. Further affected properties include ferroelectricity and photoelectric responses. The impact of dislocations on the ceramics depends on a convolution of dislocation character, core properties, possibly existing space charges, and mesoscopic structure. This is difficult to control as ceramics are usually not plastically deformable. It is thus essential to combine the understanding of mesoscopic dislocation structure and its behavior at elevated temperatures. This makes dislocations in ceramics an exciting interdisciplinary research field.

Another topic of high interest remains the fast sintering of functional ceramics. With blacklight sintering, a new method was introduced, allowing fast and energy-efficient sintering of multiple ceramics and complex ceramic structures. This means that light with a short wavelength densifies a ceramic within seconds. Investigating the underlying mechanisms and evaluating industrial-scale applications will be an important future endeavor.