About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
American Ceramic Society Journal Awards Symposium
|
| Presentation Title |
Fracture Anisotropy in Tantalum Carbide Ceramics |
| Author(s) |
Sajjad Hossain, Alyssa Stubbers, Gregory Thompson, Christopher R. Weinberger |
| On-Site Speaker (Planned) |
Christopher R. Weinberger |
| Abstract Scope |
Tantalum carbides exhibit unique fracture properties across a wide range of stoichiometries. While stoichiometric TaC exhibit modest toughness and fracture on the cube planes, Ta2C exhibits higher toughness and the tantalum carbide zeta phase can show fracture toughness around 15 MPa-m1/2. To understand how different mechanisms contribute to fracture toughness across the chemistry space, we utilize both density functional theory calculations and targeted microcantilever experiments. The DFT simulations demonstrates that the toughness of these compounds depends on types of cleavage plane orientation and carbon content. Notably, the results demonstrate that the lower symmetry compounds should have many low cleavage planes, suggesting that classical microstructural toughening may not be the sole reason for the enhanced toughness of the zeta phase ceramics. Our microcantilever experiments show good agreement with the DFT simulations when plasticity is suppressed and clearly show that plasticity and microstructural toughening are operative in these ceramics in the bulk. |