2-PHASE MICROSTRUCTURE IN PR-(FE, CO, NI)-B SINTERED MAGNETS

A search was carried out for a two-phase sintered magnet comprising Pr 2TM14B and PrTM, where TM stands for Fe, Co and Ni. Specimens were pre pared by a powder metallurgical method using alloys with compositions Pr17(Fe0.6Co0.3Ni0.1)83-xBx (x=4, 5 and 6). X-Ray diffraction and scan ning electron microscopy-energy-dispersive X-ray studies have revealed that two-phase magnets are realized for Pr17(Fe0.6CO0.3Ni0.1)78B5. Th e microstructures of these sintered magnets are characterized by Pr2TM 14B grains surrounded by an intergRanular Ni-rich PRTM phase whose thi ckness is less than about 3 mum.