Magnetocaloric properties of La0.9Pr0.1Fe11.2Co0.7Si1.1 compound through direct measurements under cyclic magnetic fields up to 30 Hz

Direct measurements of the adiabatic temperature change (ΔTad) in cyclic magnetic fields with a frequency of up to 30 Hz in the La0.9Pr0.1Fe11.2Co0.7Si1.1 alloy were carried out. For this alloy, the magnetocaloric effect (MCE) under magnetic field change of 1.8 T is 2.8 K and the temperature hysteresis does not exceed 0.5 K. Under magnetic field change of 0.62 T with frequencies of up to 20 Hz, the MCE shows a weak frequency dependence (less than 5%), while under magnetic field change of 1.2 T the frequency dependence is clear pronounced. Long-term exposure to a low frequency cyclic magnetic field does not result in a change in the MCE value, while at frequencies more than 10 Hz noticeable degradation of the MCE is observed. The results of the study show that the upper limit of the operation of magnetic refrigerators can reach several tens of Hz.