MECERDIS · Mechanics-tailored Functional Ceramics via Dislocations

Advanced functional ceramics play an indispensable role in our modern society and they are typically engineered by point defects or interfaces. The potential of dislocations (one-dimensional atomic distortions) in functional ceramics has been greatly underestimated until most recently. Exciting proofs-of-concept have been demonstrated for dislocation-tuned functionality such as electrical conductivity, superconductivity, and ferroelectric properties, revealing a new horizon of dislocation technology in ceramics for a wide range of next-generation applications from sensors, actuators to energy converters.However, it is widely known that ceramics are hard (difficult to deform) and brittle (easy to fracture), making it a great challenge to tailor dislocations in ceramics. This pressing bottleneck hinders the dislocation-tuned functionality and the true realization of dislocation technology. To break through this bottleneck, MECERDIS employs mechanics-guided design coupled with external fields (thermal, light illumination, electric field) to manipulate the 3 most fundamental factors of dislocation mechanics: nucleation, multiplication, and motion. These external fields greatly impact the charged dislocation cores in ceramics and open new routes for mechanical tuning. With these novel approaches, MECERDIS aims to generate, control, and stabilize dislocations in large plastic volumes up to mm-size with high density up to 10^15/m^2 to allow large-scale preparation for functionality assessment. Another essential benefit is, dislocations are an effective tool to combat the brittleness of ceramics by improving the damage tolerance and fracture toughness.MECERDIS will not only fulfil the key prerequisite of dislocation-tuned functionality but also secure the mechanical integrity and operational stability of future dislocation-based devices. With its success, MECERDIS will define a new paradigm of engineering functional ceramics using mechanics and dislocations.