A Comparative Study Between Low and High-Energy Milling Processes for the Production of HD PrFeCoBNb Sintered Magnets

摘要

Roller-ball milling (RBM) or planetary ball milling (PBM) have been used together with the hydrogen decrepitation (HD) process to produce sintered permanent magnets based on a mixture of Pr_(16)Fe_(76)B_8 and Pr_(14.00)Fe_(63.90)Co_(16.00)B_(6.00)Nb_(0.10) magnetic alloys. Five distinct compositions have been studied comparing low- and high-energy milling. Magnets with a particular composition and prepared using these two routes exhibited similar magnetic properties. Modifications have been carried out in the procedure of the HD stage for PBM in order to guarantee a high degree of crystallographic alignment. Pr_(15.00)Fe(69.95)Co_(8.00)B_(7.00)Nb_(0.05) magnets showed the best maximum energy product for both processing routes (～ 247 kJm~(-3) ). A significant reduction in the milling time (93%) has been achieved with high-energy processing, the greatest advantage over the low-energy route.