Effect of praseodymium addition on magnetostriction of Fe–Al alloys

Magnetostriction is essential for developing superior magnetic materials for vibration energy harvesting. In this study, rare-earth elements were added to Fe–Al melt-spun ribbons to increase magnetostriction. The crystal structure of the Fe81Al19 ribbon was estimated to be predominantly an A2-(Fe, Al) disordered phase based on XRD data and Rietveld analysis. In the Fe75Al18.75Pr6.25 and Fe75Al18.75Tb6.25 ribbons, not only the A2-(Fe, Al) phase but also the Pr2Fe17 phase and Tb2Fe17 phase were confirmed, respectively. The saturation magnetostrictive strain parallel to the magnetic field direction in Fe81Al19 ribbon shows 30 ppm. This value is consistent with the theoretical value of a {110} plane-oriented sample. While the parallel magnetostrictive strain at 0.35 T in the Fe75Al18.75Tb6.25 ribbon is 15 ppm, the Fe75Al18.75Pr6.25 ribbon is 26 ppm. This result suggests that the enhancement of magnetostriction by Pr addition may be greater compared to Tb. Consequently, adding Pr into Fe–Al alloys is an effective approach to improve magnetostrictive properties.