| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Powder Materials Processing and Fundamental Understanding
|
| Presentation Title |
Bulk Manufacturing of Metal Core Oxide Shell (MCOS) Nano-Capsules Using Iron Nanopowders |
| Author(s) |
Kavindan Balakrishnan, Krishnan S. Raja, Indrajit Charit, Josephine Selvaraj, Vaidyanathan Subramanian |
| On-Site Speaker (Planned) |
Krishnan S. Raja |
| Abstract Scope |
Oxidation of nanoparticles is different from that of bulk materials. The formation of thicker oxide films (in the micrometer range) is controlled by the Nernst-Eistein relation. The formation of thin oxide layers (smaller than 20 nm) is influenced by the electric field across the space charge layer. The nanoparticles' surface energy and radius of curvature (Gibbs-Thomson effect) affect the oxidation kinetics. This study aimed to optimize the oxidation parameters to achieve oxide layer thicknesses in the range of 10 – 20 nm. Commercially available iron nanoparticles in the size range of 40-80 nm were oxidized at 145 – 200 °C for different durations to evaluate the oxidation kinetics. The oxidation parameters were dependent on the mass of the iron particles. A logarithmic rate law was observed at low-temperature oxidation. At longer times, the initial magnetite oxide transformed to maghemite, and Kirkendall voids were observed at the core-shell interface. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Composites, Nanotechnology, Iron and Steel |