Magnetic and microstructure studies of boron-enriched (Nd0.95La0.05)(11)Fe-76.5-xCoxTi2B10.5(x=0-15) melt-spun ribbons

The magnetic properties and microstructures of rare earth lean and boron-ri ch (Nd0.95La0.05)(11) Fe76.5-xCoxTi2B10.5 (x = 0 - 15) melt-spun ribbons ha ve been investigated, Two magnetic phases, namely alpha -Fe and R2Fe14B, we re found, by thermal magnetic analysis (TMA), in all the ribbons studied. H igh intrinsic coercivity (iHc) and maximum energy product [(BH)max] values in the range of 14-18.7 kOe and 13.9-18.3 MGOe, respectively, have been ach ieved in these nanocomposites. Among compositions studied, the Co-substitut ions, x less than or equal to 10, were found to be effective in increasing the Br and (BH)max, while keeping a high value of inc, It was evidenced fro m transmission electron microscopy that the homogeneity, fine grain size, a nd high volume fraction of the R2Fe14B phase led to an increase in the iHc and maximum energy product of nanocomposites studied. The optimum magnetic properties of Br = 9.4 kc, inc = 16.1 kOe and (BH)max = 18.3 MGOe have been obtained on (Nd0.95La0.05)(11) Febal.Co10Ti2B10.5 ribbons after an optimum treatment.