ANISOTROPY AND MAGNETIC-ORDERING IN THE NEW PHASE ND3(FETI)29

Recently, a new rare-earth iron-rich phase 3:29 has been found to be stabilized using Ti. The Curie temperature T(C) = 413 K is considerably higher than in the related Nd2Fe17 compound. The easy magnetization direction lies in the basal plane of the monoclinic structure at room temperature. A magnetic anomaly has been detected at T(SR) = 233 K in the thermal dependence of the AC initial susceptibility, which has been related to a spin reorientation transition from an easy-plane phase towards an easy cone at low temperatures. Thermal expansion measurements clearly show an extra magnetic contribution at T(C), a weak anomaly being also perceptible at T(SR). The anisotropy field measurements using the SPD technique have confirmed the existence of these two magnetic phases.