Abstract :
The magnetocaloric effect (MCE) in a magnetic SmNi sample was evaluated from magnetization and heat capacity measurements. The MCE phenomena in the vicinity of magnetic phase transitions in terms of magnetic entropy change, Δ S M , and adiabatic temperature change, Δ T a d , are reported. Isothermal magnetization σ ( H ) T = const measurements at several temperatures around the transition T c = 43 K were carried out and used for Δ S M versus T calculations. A similar dependence of the magnetic entropy change − Δ S M = ( S H − S 0 ) was evaluated from heat capacity C p ( T ) measurements under zero field and 5 T. The SmNi system provides magnetic refrigerants that induce an adiabatic cooling of about Δ T a d ≈ 1.2 K during the magnetization process with a field of 5 T in the temperature range of 35–45 K. The temperature dependence of C p ( T ) is analyzed in terms of the magnetic and the lattice contributions.
