Effect of boron on the structural and magnetic properties of Co₂FeSi_1-xB_x Heusler alloys

The partial substitution of Si with B on the structural and magnetic properties of Co₂FeSi_1-xBx (x = 0-0.5) alloys was systematically investigated. X-ray and microstructural investigations show the presence of second phase at the grain boundaries which increases with increasing boron content. From thermal analysis studies, it was observed that L2₁-B2 ordering temperature remain constant whereas the melting point decreases with increase in boron addition and merges with ordering temperature at x = 0.5. The increase in T_C for the alloys x ≥ 0.25 was attributed to the increase in second phase due to boron.