Magnetic entropy change in La(Fe0.98Co0.02)11.7Al1.3

Magnetization of compound La(Fe 0.98 Co 0.02 ) 11.7 Al 1.3 was measured carefully as functions of temperature and applied field around its Curie temperature of ~198 K. Magnetic entropy change |Δ S |, allowing estimation of the magnetocaloric effect (MCE), was determined based on thermodynamic Maxwell's relation. The achieved magnitude of |Δ S | reaches 10.6 J kg -1 K -1 under a field of 5 T. The considerable entropy change is believed to be due to the high magnetization and the sharp change in magnetization at T C . It is found that the magnetic phase transition is completely reversible in temperature, indicating a nature of second-order phase transition.