Application of Transmission Electron Microscopy in Investigations of Structural Anisotropy of NdFeB Magnets

Rapid quenched powdered ribbons Nd_13.6Co_6.6Ga_0.6B_5.5Fe_73.7 (at. %) were hot pressed at 700° C. Next, the alloys were subjected to die-upset process through heating to 600, 750 and 1000° C and forged at a rate of έ = 1x10^-3 s^-1 to the stage of deformation equal to ε = 60%. Directional grain growth occurs in the material during this treatment, which is beneficial due to the anisotropic magnetic properties obtained in such materials. Detailed analysis performed using transmission electron microscopy shows the tendency of micro structural changes in the magnet resulting from the application of different temperatures of the processes.