Magnetocaloric effect in melt-spun rare earth intermetallic compound ErAl2

Abstract

Laves phase rare earth intermetallic compound ErAl2 (Cubic, MgCu2-type) has been prepared by melt-spinning process. Analysis of powder X-ray diffraction data of melt-spun ErAl2 yields crystallite size of about 54 nm. Transmission electron microscopy image reveals particles of size ∼70 nm. The melt-spun ErAl2 orders ferromagnetically ∼10 K (TC) whereas the ferromagnetic ordering temperature is ∼14 K for the arc-melted ErAl2 compound. From the magnetization vs field data, isothermal magnetic entropy change (ΔSm) has been computed as a function of temperature near TC. The maximum ΔSm value in the melt-spun ErAl2 is ∼ −34 Jkg−1K−1 at 14 K for 70 kOe field change whereas the corresponding value in the arc-melted sample is ∼ −42 Jkg−1K−1 at 16 K. Thus, rapid solidification results in crystalline, coarse grained ErAl2 with submicron sized particles leading to only minor changes in the magnetic and magnetocaloric properties.