Substitution effects on the magnetic phase transition and magnetocaloric effects in nanolaminated AlFe2B2 alloys

Substitution effects of V, Ti and C in AlFe 2−x V x B 2 ( x ≤ 0.15), AlFe 2−y Ti y B 2 ( y ≤ 0.15) and AlFe 2 B 2− z C z ( z ≤ 0.2) alloys have been investigated. The main phase of these alloys is crystallized in the orthorhombic Cmmm-type structure. The Curie temperature ( T c ) of these compounds can be tuned from 278 K to be around 300 K depending on the substitution amount. No thermal and magnetic hysteresis can be observed, suggesting the magnetic transition of these alloys is the second-order nature. For a field change of 7 T, the maximum of entropy change (−ΔS max ) of 4.0 J Kg −1  K −1 , 4.2 J Kg −1  K −1 and 3.9 J Kg −1  K −1 has obtained in AlFe 1.9 V 0.1 B 2 , AlFe 1.9 Ti 0.1 B 2 and AlFe 2 B 1.9 C 0.1 alloys. Tunable T c and wide temperature span in AlFe 2 B 2 phase suggest that AlFe 2 B 2 -base alloys have a potential application as a refrigerant in magnetic refrigeration.