| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
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| Symposium
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Functional Defects in Electroceramic Materials
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| Presentation Title |
Ceramics Are Brittle. Can Dislocations Change That? |
| Author(s) |
Lukas Porz, Arne Klomp, Xufei Fang, Ning Li, Can Yildirim, Carsten Detlefs, Enrico Bruder, Marion Höfling, Wolfgang Rheinheimer, Eric Patterson, Peng Gao, Karsten Durst, Atsutomo Nakamura, Karsten Albe, Hugh Simons, Jürgen Rödel |
| On-Site Speaker (Planned) |
Lukas Porz |
| Abstract Scope |
While the effect of dislocations on functional properties is increasingly appreciated, dislocations have barely been considered for toughening ceramics. Despite outstanding deformability of a range of ceramic single crystals (e.g., LiF, MgO or SrTiO3) at room temperature, an effect of dislocations on fracture toughness was rarely observed. Why?
Here, we show that introducing a high dislocation density can allow local plasticity which is key for desirable mechanical properties. With local deformation enabled, stress concentrations around flaws or indents can be mitigated by plastic flow. In effect, crack nucleation and propagation are substantially reduced [1].
In consequence, dislocations can be a new avenue to combat short cracks and increase device reliability. Conventionally sintered samples, however, are not suitable as this process renders ceramics dislocation-free.1)Porz et al., Materials Horizons, 2021 (DOI:10.1039/d0mh02033h) |