Magnetocaloric Effect of Fe(Rh1−xPdx) Alloys

Magnetocaloric effects of Fe 49 (Rh 1-x Pd x ) 51 alloys with x = 0.0, 0.01, 0.03, 0.06, 0.07, 0.08, and 0.09, were investigated using resistivity, magnetization, specific heat, and direct measurement of the adiabatic temperature change AT. Magnetization measurements yielded experimental values of the isothermal magnetic-entropy change AS for all the samples. The critical temperature of the anitiferromagnetic-ferromagnetic transition was found to depend largely on the substitution concentrations of Pd. A broad peak in AS, up to 1.7 J·mol -1 K -1 and some 90 K broad around room temperature, was observed with a field change of ΔB = 0 to 7 T for Fe 49 (Rh 0.97 Pd 0.03 ) 51 . The specific heat data of Fe 49 (Rh 0.97 Pd 0.03 ) 51 made it possible to estimate the AT values for various external fields. This estimated value of AT compares well with the value measured directly using a thermocouple.

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