A history of development of permanent magnets
Technical University of Darmstadt wave a longstanding experience on production and characterization of permanent magnets. Some major research topics are: Hot-deformation, recycling, grain boundary diffusion process, Rare-earth free magnets, coercivity and anisotropy mechanism, and advanced multi-scale modeling.
Magnetic imaging using techniques like Kerr microscopy and magnetic force microscopy (MFM) can probe the magnetic characteristics of grains and domains of a permanent magnet at the micron-scale.