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In this work, using a scaling data method based on the mean-field theory (MFT), magnetization isotherms M (H, T) and magnetic entropy change − S M (T) curves have been simulated using MFT combined with the Bean-Rodbell model which verified the secondorder phase transition for Gd 3 Ni 2 and Gd 3 CoNi compounds. Under a low value of magnetic field H, M (T) and − S M (T) curves have been successfully simulated and some magnetocaloric properties have been evaluated using the phenomenological model.

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In this work, an overview of the Weiss molecular mean-field theory, the Bean-Rodbell model, and the Landau theory is presented, providing the theoretical background for simulating the magnetocaloric properties for La0.6Ca0.2Na0.2MnO3 manganite. Results showed that sample exhibits second order ferromagnetic (FM)paramagnetic (PM) magnetic phase transition and relatively higher values of magnetic entropy change (-∆SM). In application point of view, this material can be used in magnetic refrigeration technology. The theoretical values of -∆SM determined using each theory agree well with the experimental ones estimated from Maxwell relations. In other part, a good agreement in the spontaneous magnetization values, Mspont(T), estimated from (-∆SM vs. M 2 ) and (H/M vs. M 2 ) data was found. Also, the values of the critical exponent (β) found from both methods are close and check that the mean field model is adequate to study the MCE in La0.6Ca0.2Na0.2MnO3 sample.