Production by planetary ball milling and phase transition of Fe-Nd-Nb nanocrystalline alloys

The main aim of the present work is to study the synthesis and phase transition of Fe77Nd10Nb7B4Cu1Ag1 magnetic nanostructured materials under high temperature conditions. Fe77Nd10Nb7B4Cu1Ag1 alloy powders were prepared by high energy ball milling using milling times of up to 50 h. The as milled alloys consist of an iron based nanocrystalline solid solution with an average grain size of 12.5 nm (after 50 h milling time). The evolution of grain size during the ball milling process and investigations under external temperatures up to 875 degrees C were evaluated using synchrotron radiation X-ray diffraction and alpha-Fe ->gamma-Fe phase transition (onset transition temperature T-x1=825 degrees C), and the formation of Fe17Nd2B compound (onset temperature T-x2=875 degrees C) was observed. The X-ray experiments were performed at the B2 instrument beamline at DESY/HASYLAB, Hamburg, Germany.