Magnetism of a sigma-phase Fe60V40 alloy: Magnetic susceptibilities and magnetocaloric effect studies

Magnetic properties of a sigma-phase Fe60V40 intermetallic compound were studied by means of ac and dc magnetic susceptibility and magnetocaloric effect measurements. The compound is a soft magnet yet it was found to behave like a re-entrant spin-glass system. The magnetic ordering temperature was found to be T-C approximate to 170 K, while the spin-freezing temperature was similar to 164 K. Its relative shift per decade of ac frequency was 0.002, a value smaller than that typical of canonical spin-glasses. Magnetic entropy change, Delta S, in the vicinity of TC was determined for magnetic field, H, ranging between 5 and 50 kOe. Analysis of Delta S in terms of the power law yielded the critical exponent, n, vs. temperature with the minimum value of 0.75 at TC, while from the analysis of a relative shift of the maximum value of DS with the field a critical exponent Delta = 1.7 was obtained. Based on scaling laws relationships values of other two exponents viz. beta = 0.6 and gamma = 1 were determined. (C) 2017 Elsevier B.V. All rights reserved.