Title :
Improved hot workability and magnetic properties in NdFeCoGaB hot deformed magnets
Author :
Kirchner, A. ; Hinz, D. ; Panchanathan, V. ; Gutfleisch, O. ; Müller, K.H. ; Schultz, L.
Author_Institution :
Inst. of Metallic Mater., IFW Dresden, Germany
fDate :
9/1/2000 12:00:00 AM
Abstract :
The hot workability and the magnetic properties of die-upset and backward extruded melt-spun magnets with the composition of Nd14.2 Fe80.8B5 (MQP-A), and Nd13.6Fe 73.6Co6.6Ga0.6B5.6 (MQU-F) have been investigated. Magnets of MQU-F powder show an improved hot workability and better magnetic properties compared to the ternary alloy. Remanence, coercivity and energy product of die-upset MQU-F magnets were found to be Bτ=1.3 T, μ0jHc=1.7 T, and (BH)max=326 kJm-3, respectively. SEM and TEM investigations revealed a smaller average grain size in MQU-F magnets, which has a positive effect on the hot workability and magnetic properties. Radially oriented ring magnets were produced from both alloys and characterized magnetically. The temperature coefficients of ring magnets were determined to be β=(dHc/dT)=-0.6%/°C and α=(dBτ/dT)=-0.09%/°C. A higher deformation speed can be used for the production of MQU-F magnets, which should make the process more economic
Keywords :
boron alloys; cobalt alloys; coercive force; ferromagnetic materials; gallium alloys; grain size; hot working; iron alloys; neodymium alloys; permanent magnets; remanence; Nd13.6Fe73.6Co6.6Ga0.6 B5.6; Nd14.2Fe80.8B5; NdFeCoGaB hot deformed magnets; SEM; TEM; backward extruded melt-spun magnets; coercivity; die-upset; energy product; higher deformation speed; hot workability; magnetic properties; remanence; temperature coefficients; Coercive force; Grain size; Iron; Magnetic properties; Magnets; Neodymium; Powders; Remanence; Temperature; Workability;
Journal_Title :
Magnetics, IEEE Transactions on
