Production of thick high-performance sintered neodymium magnets by grain boundary diffusion treatment with dysprosium-nickel-aluminum alloy

摘要

A novel grain boundary diffusion (GBD) treatment with a Dy-Ni-Al eutectic alloy powder allowed Dy to penetrate into sintered plates of Nd-Fe-B magnet as thick as 5 mm. The coercivity of the magnet was increased from a value of 1160 kA/m (14.5 kOe) to 1760 kA/m (22 kOe). This was achieved without any marked decrease in remanance and with a high squareness.