Coercivity dependency of sintered NdFeB magnets on Al content and the alloying route

A significant effect on the intrinsic coercivity (iH/sub c/) of sintered magnets was observed while comparing two methods of doping Al into NdFeB alloy at the preparation stage. Adding 0.25% Al by weight via FeB resulted in a 20% increase of iH/sub c/ over doping pure Al. It is believed that changes in the sintered microstructure are responsible for the observed effect.<
>