BaFe/sub 12-x-x'/M/sub x/ M'/sub x'/O/sub 19/ particles grown by a modified flux method (M: Co/Zn, M': Mn/Sn/Sb)

Magnetic properties of Sn–Mg substituted strontium hexaferrite nanoparticles synthesized via coprecipitation method

“…The small difference between the results could be due to agglomeration of particles in PSA. Again, the measurements showed that the mean particle size of hexaferrite was decreased by increasing the Sn-Mg content and it was in agreement with other researches [22].…”

Permanent magnets based on R-Fe-B and R-Fe-C alloys

“…Coercive fields at 150 • C versus annealing temperature (1 h annealing time) for (NdDy) 15 (Fe, Co, Mo, Al) 77 B 8 magnets (Eckert et al 1993). Tokuhara et al 1989, Withey et al 1989, Zhou G F et al 1989, Kim K Y et al 1991, Chen Z M et al 1993. The dependence of the coercive field on the post-sintering thermal treatment was attributed by Eckert et al (1987) to structural changes of intergrain boundary region and the surface region of Nd 2 Fe 14 B grains.…”

“…An additional Nd-Fe-O intergranular phase has a strong effect on coercivity and their temperature dependence (Chen Z M et al 1993, Besenicar et al 1992. The MgO, Al 2 O 3 , Cr 2 O 3 , ZnO and CaO enhance the coercivity and MgO and ZnO improve the thermal stability.…”

“…The MgO, Al 2 O 3 , Cr 2 O 3 , ZnO and CaO enhance the coercivity and MgO and ZnO improve the thermal stability. An intergranular phase with a composition close to 70Nd-22O-5Fe-(1-3 M), M = Mg, Zn, Al, Mn, Zr, Ca appears in the oxide-doped magnets, due to a reaction between the oxide additives and the intergranular phases (Chen Z M et al 1993(Chen Z M et al , 1995(Chen Z M et al , 1996. Thus, a small amount of oxygen in the intergranular regions seems to be helpful in…”