Structure, magnetic properties and magnetocaloric effect of La1+xFe10,5-xCoSi1,5 ribbons

Abstract

In this work, the authors investigated the influences of La-concentration and annealing process on structure, magnetic properties and magnetocaloric effect of La_1+xFe_10.5-xCoSi_1.5 (x = 0, 0.5, 1 and 1.5) ribbons prepared by melt-spinning method with tangential velocity of copper wheel of 20 m/s. The ribbons were subsequently annealed at different temperatures (from 1223 K to 1323K) for 1 hour. The results showed that the structure and magnetic properties of the alloy remarkably depended on the concentration of La and annealing process. With increasing La-concentration, the glass forming ability (GFA) of the alloy was increased. Curie temperature of the alloy reduced with increasing La-concentration. The magnetic entropy change (DSM) of the alloy achieved around room temperature was larger than 1 J.kg-1.K-1 (under magnetic change DH = 12 kOe).