Adiabatic Temperature Changes at Structural and Magnetic Phase Transitions in Ni45Mn43CoSn11 at High Magnetic Fields

The adiabatic temperature change (ATad) in Ni 45 Mn 43 CoSn 11 has been measured by a direct method in magnetic field changes up to 14 T. Large reversible magnetocaloric effects resulting in AT ad of about = -11 and 5 K have been observed for magnetic field changes of 14 T at the magnetostructural (T A ~ 260 K) and magnetic transitions (T C ~ 320 K), respectively. The impact of the thermomagnetic history on AT ad at high magnetic fields has been reported. The significant observed changes in the relaxation time of AT ad , depending on the type of the phase transitions, magnetization, and demagnetization cycle are discussed.