Magnetocaloric and cooling properties of the intermetallic compound AlFe2B2 in an AMR cycle system

摘要

In this work, we report a detailed theoretical study dealing with the magnetic and thermal features of the intermetallic compound AlFe2B2 close to room temperature. The magnetocaloric properties in terms of both adiabatic temperature (Delta T-ad) and magnetic entropy (Delta S-mag) changes were determined using the Monte Carlo approach, while the thermodynamic performances were simulated according to the active magnetic refrigeration (AMR) model. Under a magnetic field changing from 0 to 5 T, the Delta S-mag and Delta T-ad reach maximum values of 7.75 J/kg K and 3.74 K close to 290 K, respectively, being in good agreement with previously reported experimental values. In contrast, the calculated relative cooling power (RCP) was found (480 J/kg) to largely exceed the reported experimental value in early works. On the other hand, the implementation of AlFe2B2 as a refrigerant in a 1T-AMR device would enable to generate a maximum no-load temperature span of about 10 K and a maximum cooling power of 50 W for a low operating frequency of 0.5 Hz. These findings unveil that the relatively cheaper AlFe(2)B(2)compound and its derivatives could be a promising alternative to the rare earth-based alloys in magnetic refrigeration.