Rare earth intermetallic compounds are widely studied for their magnetocaloric properties. These are usually prepared by electric arc-melting. By melt-spinning the arc-melted ingot, polycrystalline samples with micron- or sub-micron sized grains could be formed. These melt-spun ribbons exhibit magnetocaloric properties similar to their arc-melted analogues [1]. In the present work, structural and magnetic properties of rare earth dialuminide intermetallic compounds are studied in their melt-spun form. The compounds RAl2 (R = Gd, Er) are prepared by arc-melting and melt-spinning. These compounds crystallize in cubic structure (Fd-3m). While nanosized grains are observed in both the melt-spun samples, these were relatively bigger in the melt-spun ErAl2 sample. A sluggish paramagnetic to ferromagnetic transition occurs at a Curie temperature (TC) of 136 K in the melt-spun GdAl2. This value is about 30 K smaller than the ferromagnetic transition temperature of the arc-melted GdAl2. It is found that melt-spinning process results in broadening of the peak in the isothermal magnetic entropy change vs temperature plot of melt-spun GdAl2 without compromising on the magnetocaloric effect. However, the coarse-grained melt-spun ErAl2 exhibits more or less similar behaviour as that of the bulk, arc-melted ErAl2.

References
1. J. Lyubina, R. Schafer, N. Martin, L. Schultz and O. Gutfleisch, Adv. Mater. 22 (2010) 3735
2. Mitali Madhusmita Prusty, J. Arout Chelvane and R. Nirmala, Mater. Res. Express 7 (2020) 064001