The structure and magnetocaloric effect of Mn38Fe22Al40Bx alloys

The structural properties and magnetocaloric effect of Mn₃₈Fe₂₂Al₄₀B_x alloys are investigated in this study. The alloys are prepared by arc melting and heat treated at 1000 K for 7 days under an argon gas atmosphere. X-ray diffractometry and vibrating sample magnetometry are used for crystal structure and magnetization measurements, respectively. Observations show that boron addition into the Mn₃₈Fe₂₂Al₄₀ alloy enhances the saturation magnetic moment and therefore increases the magnetic entropy change. Results also show that the Curie temperature increases when boron atoms enter the interstitial positions but decreases when boron atoms occupy the substitution positions.