The magnetic and magnetocaloric properties of Al-rich Al0.85+xSi0.15Fe2B2 compounds prepared by drop-casting

Owing to the relative abundance of its constituent elements and large magnetocaloric properties observed near room temperature, the AlFe2B2 system has attracted much attention recently. Here, we have studied the magnetic and magnetocaloric properties of Al0.85+xSi0.15Fe2B2 (x = 0.2, 0.4) prepared by drop-casting followed by annealing and acid treatment. The second order ferromagnetic phase transitions were observed near room temperature (similar to 298-305 K) and peak magnetic entropy changes (-delta S-M) of more than -6 J kg(-1) K-1 were observed for a field change of 5 T. The results are discussed in terms of the impurity phases formed in the compounds due to excess aluminum.