| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Biological Materials Science
|
| Presentation Title |
Nanostructural and Nanomechanical Mapping of Sea Urchin Tooth |
| Author(s) |
Riley McCarry, Alyssa Stark, Gang Feng |
| On-Site Speaker (Planned) |
Riley McCarry |
| Abstract Scope |
Sea urchin tooth (SUT) is composed of calcite crystals and organic molecules as unique hierarchical nanocomposite, which keeps sharpening during use. To understand the self-sharping behavior, a comprehensive understanding is needed. In this study, the SUT’s longitudinal section has been characterized for the first time using confocal Raman microscopy for nanostructural mappings (Ca and Mg) and nanoindentation for nanomechanical mappings (modulus E and hardness H). The E and H correlate well with the Mg concentration in calcite, and the stone region contains much higher Mg concentration and is ~30% stiffer and ~30% harder than the surrounding regions. Moreover, E, H, Mg and Ca distributions show two hierarchical levels of periodicity: (1) a large one (~10 micron), matching that of plates, and (2) a small one (~ 1 micron). Indentation-induced cracking is also studied to find the intrinsic preferential cracking path. This provides important insights on SUT’s self-sharpening mechanism. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Biomaterials, Mechanical Properties, Other |