High-field magnetic properties in Nd–Fe intermetallic compound

Abstract On the basis of the molecular field theory, an improved two-sublattice model is applied to analyze the magnetic properties in Nd 2 Fe 17 H x ( x =0, 3 and 4.9) under high magnetic fields. As is known, two types of magnetic ions exist in Nd–Fe intermetallic compound. Here, the exchange interactions of Nd–Nd, Nd–Fe and Fe–Fe are taken into account. And, as to the ferromagnetic compounds, we define the effective exchange field H ex = νχ eff H e , where ν the molecular field coefficient, χ eff the effective magnetic susceptibility, and H e the external magnetic field. Meanwhile, the field-dependence characteristics of magnetization at different temperatures are discussed. Also, the parameters α A and α B , associated with v and χ eff , are defined, and the field-dependence, temperature-dependence characteristics are analyzed. Additionally, it is confirmed that the hydrogen content shows great influence on the magnetic properties in Nd 2 Fe 17 H x compound.