Local profile dependence of coercivity in (MM 0.3 Nd 0.7 )-Fe-B sintered magnets

摘要: Abstract Two magnets with the same nominal composition of (MM 0.3 Nd 0.7 )-Fe-B (Marked as A) and [(La 0.27 Ce 0.53 Pr 0.03 0.17 ) ]-Fe-B B) were prepared using traditional powder metallurgical process, respectively. In order to point out difference between two magnets, magnetic properties, microstructure domain both investigated. Both have elements, but different raw materials misch-metal (MM) La/Ce/Pr/Nd pure metal, which induces properties. The magnet A B r 13.1 kGs, H cj 7.6 kOe, (BH) max 37.8 MGOe 13.4 kGs, 5.8 kOe, 34.5 MGOe are obtained. Although similar , has higher coercivity than that B. According refined results characteristic X-ray diffraction peaks, there is a hard main phase anisotropy field ( in opposite case happens on SEM images demonstrate more continuous RE-rich smaller grain size compared B, contributes enhancing coercivity. addition, phases [Nd 0.82 (La, Ce) 0.18 0.75 0.25 detected by EDX calculation, observed domains again. Compared 2:14:1 contain less phases, also leads due among 2 Fe 14 La phases. Therefore, it concluded MM substitution could exhibit better properties (La )-metal substitution. Furthermore, applications beneficial fabricate (MM, Nd)-Fe-B permanent lower cost.