|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Materials Science for High-Performance Permanent Magnets
||Grain Boundary Diffusion of Co, Cu and Nb as Function of Temperature in NdFeB
||Gino Hrkac, Thomas Schrefl, Johann Fischbacher, Thomas Ostler, Richard Evans, Sam Westmoreland, Michael Winklhofer, Roy Chantrell, Gergely Zimanyi
|On-Site Speaker (Planned)
We perform molecular-dynamics simulations to understand the impact of Co,Cu and Nb diffusion on the NdFeB-phase at different temperatures 300-600K. It is shown that for large Co-concentrations a disruptive behavior of Co in the NdFeB-matrix can be observed. This distortions are found to lead to periodic displacement, indicating that a strain is acting on the whole crystal and produces a profiling effect. Temperature studies show doping materials such as Co, Nb, and Cu diffuse easier into a Fe-rich boundary phase than into a Nd-rich. By doing that the doping materials produce sharp distortion profiles, 5-10Angstrom. Quantitative analysis shows that smaller infiltration-profiles produce sharp transition phases, e.g. Cu, hence improving anisotropy profile. Further we show that all dopants and especially Cu tends to accumulate at the interface between two phases as function of temperature. In conclusion, Cu and Co can be used to reduce strain effects at the interface.