Separable behavior of magnetic heat capacity and thermal expansion in Ni, and their relation

The magnetic phase in Ni shows an endothermic peak in heat capacity and a positive peak of thermal expansion near magnetic phase transition. The relation between heat capacity and thermal expansion of the magnetic transition is not yet studied. In this study, we apply the new heat capacity model to explain the thermal properties in Ni with magnetic phase transition. The starting and ending temperatures of the magnetic transition are first accurately determined only with experimental heat capacity and thermal expansion. The heat capacity and thermal expansion of the magnetic transition, separated from the total heat capacity and thermal expansion by the perfected model, show a linear relation. The separable behavior and the linear relation of thermal properties in Ni are helpful to further understand the thermodynamic properties of multi-phase solids.