XLV. Magneto-thermal effects in ferromagnetics

Abstract

A theoretical treatment is presented of experimental results on the adiabatic temperature changes accompanying the magnetization of ferromagneties in low and moderate fields. The relevant thermodynamic relations are derived, in particular those relating the adiabatic change of temperature with field and the change of magnetization with temperature at constant field. Consideration is given to the various elementary processes by which change of magnetization occurs, namely, change of intrinsic magnetization, rotation of the domain magnetization vector in the anisotropic crystalline field, in its pure form and as modified by strains, and the reversible and irreversible movement of domain boundaries. The thermal changes associated with these processes are considered and the atomic interpretation of the effects is discussed.