Highly deformable ceramic composites for ceramic forging and high temperature applications

Introduction

Despite their incredible durability, ceramics used are hampered by two limitations: they are difficult to manufacture compared with continuous manufacturing of metals and polymers, and they are brittle, even at relatively high temperatures. Both these limitations stem from their low fracture toughness and the absence of plastic deformation mechanisms.

Project Goals

One of the goals of my ERC SSTEEL was to find a way to toughen ceramic composites by introducing strain hardening mechanisms at the nanometric scale. We succeeded and produced a ceramic composite that shows plastic deformation of at least 14% and toughness two orders of magnitude higher, in terms of energy release rate, than conventional structural ceramics at temperatures around 1000°C.

Applications

These temperatures are close to the ones used to hot forge steel and thus open two new application avenues for these deformable ceramics:

1. Enabling ceramics forging, using preform to produce complex shapes in a quick and simple way.
2. Using this high toughness to produce structural ceramics for high-temperature applications, in burners or even engines.

Proof-of-Concept Project Objectives

The goal of this Proof-of-Concept project is three-fold:

1. To work on the ceramic composition to lower the temperature needed for deformation or improve their high-temperature mechanical resistance.
2. To develop the forging of ceramics beyond the initial results to showcase the capabilities to future clients.
3. To start testing the continuous processing of these composites.

Conclusion

Succeeding in these goals holds promises for cheaper and faster manufacturing of complex-shaped ceramic parts, opening a wealth of potential applications previously limited to metals or polymers, as well as developing more ductile high-temperature structures.