Investigation of the inverse magnetocaloric effect with the fraction method.

In this study, we examine Ni49Nb1Mn36In14 (nom. at.%) magnetic shape memory alloy (MSMA) to illustrate the inverse magnetocaloric effect using the fraction method. The magnetic entropy change, ∆S_mag, was calculated with both, the fraction method and the thermomagnetic Maxwell relation. Our results demonstrate that there exists a large magnetization difference between field-cooling and field-heating histories in Ni49Nb1Mn36In14 (nom. at.%) MSMA, which can be attributed to the pinning of lattice entropy and magnetic entropy, as it is well-known that the temperature and applied magnetic fields have an opposing effect on the total entropy change. In addition, we describe the inverse magnetocaloric effect and the contradictory roles on the total entropy change between the two stimuli via the fraction method.