| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Alloy Phase Transformations at Elevated Temperatures
|
| Presentation Title |
Study of Thermal Decomposition of γ’-Fe4N Using Molecular Dynamics Simulation |
| Author(s) |
Jianxin Zhu, Jian-Ping Wang |
| On-Site Speaker (Planned) |
Jianxin Zhu |
| Abstract Scope |
Recent research demonstrated experimentally through thermally quenching using γ’-Fe4N as precursor to synthesize α”-Fe16N2 in bulk format, a promising environment- friendly rare-earth-free permanent magnet with ultra-high saturation magnetization. In this research, we investigated γ’-Fe4N thin film thermal decomposition and potential localized fcc-bct phase transition using Molecular Dynamics (MD) simulation. As the nitrogen content is higher in γ’-Fe4N (5.9 wt.%) than that in α’-Fe8N or α"-Fe16N2 (3 wt.%), Localized Nitrogen "depletion” needs to occur during thermal decomposition to form possible bct Fe-N solid solution and/or α’ phase. Nitrogen bond forming and Nitrogen diffusion are the two pathways in reduction of Nitrogen in γ’-Fe4N. “Nitrogen-rich” and “Fe-rich” grain-boundary models are introduced to study these reduction mechanisms. We applied MEAM Fe-N force field, simulated Nitrogen bond form/breaking and local Nitrogen displacement analysis in the thermostat-controlled heating/quenching simulation. XRD and formation energy calculation are used to detect the potential phase transition. |