How extrinsic is the coercivity in NdFeB bonded magnets?.

Abstract

The influence of the densification step, performed by uniaxial pressing at room temperature, on the coercivity μ0Hc of NdFeB bonded magnets has been analyzed. The mass density does not play any role on μ0Hc of non-cured magnets prepared by the mentioned method. Due to the brittle and intergranular character of the Nd2Fe14B-based phase fracture, the nano-sized grains are not affected or the modification is negligible, which maintains μ0Hc unchanged. After curing, the intrinsic coercivity of the magnets is reduced as a function of the compaction pressure increase