| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
100 Years and Still Cracking: A Griffith Fracture Symposium
|
| Presentation Title |
The Maximum Limit of Compressive Strength and Hardness of Nanocrystalline MgAl2O<Sub>4 Spinel |
| Author(s) |
Jessica M. Maita, Jacob R. Davis, James Wollmershauser, Edward Gorzkowski, Boris Feigelson, Seok-Woo Lee |
| On-Site Speaker (Planned) |
Jessica M. Maita |
| Abstract Scope |
Transparent materials are used extensively due to their ability to transmit light and provide physical protection from external chemical and mechanical interactions. Transparent nanocrystalline MgAl2O<Sub>4 has been sintered with grain sizes ranging from 3.7 to 80 nm, the smallest currently reported. Nanoindentation and micropillar compression are performed to elucidate the effect of grain size on plasticity and fracture. We found that both the maximum hardness in nanoindentation and the maximum fracture strength in micropillar compression appear at 10.5 nm grain size. High-resolution transmission electron microscopy and molecular dynamics simulations revealed that grain boundaries play an important role in the determination of the critical grain size regardless of different deformation modes; as fracture initiators in uniaxial compression and plasticity barriers/carriers in nanoindentation. These results provide a better understanding of the mechanical behavior and help improve the design of transparent armor with superior protection capability. |
| Proceedings Inclusion? |
Planned: |