A01

Currently, the achievable coercivities in permanent magnet materials do not surpass 20 % of their intrinsic limits imposed by the respective anisotropy fields. To address this, we focus in A01 on realizing maximum hysteresis in permanent magnets by new strategies for magnetic hardening. A novel top-down approach that exploits phase decomposition reactions leading to nanocomposite microstructures with domain wall pinning sites (“perfect defects”) in Nd₂Fe₁₄B will be demonstrated for the first time. In a perspective, we pursue an additional strategy where exchange coupling between a ferromagnetic matrix and antiferromagnetic precipitates results in a large coercivity. This is developed based on the concept of exploiting the relatively high exchange energy, as compared to the anisotropy energy.