Chikara Ishizaka

Large particle size Sm2Fe17Nx compounds by hydrogen treatment

Large particle size Sm2Fe17Nx with a low oxygen content has been produced by treating Sm2Fe17 with hydrogen before nitrogenation. Large Sm2Fe17Nx particles of more than 2 mm include nearly 3.0‐wt. % nitrogen and a magnetization level of 140 emu/g. The hydrogen decrepitation behavior was not observed for this alloy and the size of samples were not changed after hydrogen treatment and nitrogenation. It is thought that hydrogen absorption and desorption increase the gas‐solid reaction area significantly. The oxygen content of these particles is less than 200 ppm because the fine pulverization step was skipped. The relation between the nitrogen content and magnetization of Sm2Fe17Nx will be presented.

Maqnetic Properties And Phase Transfer Of SmFe/sub 2/And SmFe/sub 3/ Intermetallic comp ounds By Nitrogenation.

Magnetic properties and phase transfer of SmFe/sub 2/ and SmFe/sub 3/ compounds before and after nitrogenation are examined. It is found that SmFe/sub 2/ and SmFe/sub 3/ specimens show ferromagnetic properties with saturation magnetization of around 60 and 80 emu/g and Curie temperature of 425 degrees C and 410 degrees C, respectively. After nitrogenation, these compounds are thought to be decomposed into SmN and alpha Fe, considering X-ray diffraction and thermomagnetic analysis. It is assumed that the produced soft magnetic phase would deteriorate the magnetic properties of Sm rich Sm/sub 2/Fe/sub 17/N/sub x/ type magnets. >