Development of the Bonded Magnets Mixed with Different Magnetic Powders

Abstract

Rare-earth magnets composed of two or more kinds of magnetic powders have some excellent properties, because some disadvantages of one kind of magnetic powders are compensated by the other. Temperature properties are improved by the interparticle interaction in the Sm₂Co₁₇+Sm₂Fe₁₇N_x resin bonded magnets. Mechanical strength of Sm₂Co₁₇+ HDDR-processed Nd₂Fe₁₄B bonded magnets is higher than that of HDDR-processed Nd₂Fe₁₄B bonded magnets. In the Sm₂Fe₁₇N_x+ Nd₂Fe₁₄B bonded magnets, high energy product is achieved. With proper adjustment of the preparation conditions, the magnetic properties of the Sm₂Fe₁₇N_x+ Nd₂Fe₁₄B bonded magnet are Br=1.08T, H_cj=967kA/m, (BH)max=200kJ/m³. The temperature coefficients of Br and Hcj in this magnet are -0.07%/°C and -0.51 %/°C.