Full magnetization process of 3d−4f hard magnetic materials in ultrahigh magnetic fields (an example: RFe11Ti)

The prospects of using the free-powder high-field magnetization method for a quantitative study of inter-sublattice exchange interaction in 3d−4f hard magnetic materials are analyzed. Such analysis is stimulated by the availability of pulsed magnetic fields ∼103 T generated by implosion. Particular attention is paid to effects due to magnetic anisotropy, essential for these materials. The 3d−4f ferrimagnets where both sublattices contribute positively to the easy-axis anisotropy are shown to be suitable objects of study by the free-powder method, because (i) anomalies in their low-temperature magnetizatization curves are sharp and (ii) anisotropic effects can be allowed for without quantitative knowledge of the anisotropy constants. Moreover, these “good” hard magnetic materials can be brought into metamagnetic regime by diluting the rare earth sublattice with nonmagnetic yttrium; then, regardless of the anisotropy constants, the magnetization curve at low temperatures has just one steplike anomaly, the t...