Influence of the demagnetizing field on the determination of the magnetocaloric effect from magnetization curves

The influence of the demagnetizing factor (N) on the magnetic entropy change (ΔSM) curves is studied for materials with a second order phase transition. For this purpose, a soft magnetic amorphous ribbon is measured for different orientations of the magnetic field with respect to the plane of the sample. For temperatures below the Curie temperature (TC), the increase in N causes a decrease in ΔSM, while for temperatures above TC no change in the shape of the curves has been found for the different orientations, as expected. In order to eliminate this influence of N and compare the ΔSM(T) curves for samples with different shapes, the recently proposed universal curve for the magnetocaloric effect can be used.