Giant magnetocaloric effect for (Mn, Fe, V)2(P, Si) alloys with low hysteresis

The Fe₂P type Mn–Fe–P–Si alloys exhibit a giant magneto-elastic first-order transition, but the large hysteresis limits their performance. Crystal structure evolution and magnetocaloric performance were investigated by varying the Mn and Fe contents at a constant V substitution of 0.02 in Fe₂P-type (Mn_1.17-xFe...

Magnetocaloric effect in the (Mn,Fe)₂(P,Si) system: From bulk to nano

In the field of nanoscale magnetocaloric materials, novel concepts like micro-refrigerators, thermal switches, microfluidic pumps, energy harvesting devices and biomedical applications have been proposed. However, reports on nanoscale (Mn,Fe)₂(P,Si)-based materials, which are one of the most promising bulk materials for solid-state...

Étude des performances du cycle frigorifique régénératif de Brayton utilisant un nouveau matériau composite Mn-Fe-P-Si avec hystérésis thermique comme milieu de travail

MnFeP(As, Ge, Si) series compounds are three kinds of MnFe-based magnetocaloric materials, which have giant magnetocaloric effect. In this work, the experimental characteristic curves of new style Mn-Fe-P-Si materials, numbered as 1: Mn_1.32Fe_0.67P_0.52Si_0.49, 2: Mn_1.37Fe_0.63P...

Ultra-low Hysteresis in Giant Magnetocaloric Mn_1-xV_xFe_0.95(P,Si,B) Compounds

Large thermal hysteresis in the (Mn,Fe)2(P,Si) system hinders an efficient heat exchange and thus limits the magnetocaloric applications. Substitution of manganese by vanadium in the Mn1-x1Vx1Fe0.95P0.593Si0.33B0.077 and Mn1-x2Vx2Fe0.95P0.563Si0.36B0.077 compounds enable a significant reduction in the thermal hysteresis without losing the giant...

Tuning the magneto-elastic transition of (Mn,Fe,V)₂(P,Si) alloys to low magnetic field applications

The first-order magneto-elastic transition in the Mn–Fe–P–Si alloys can be tailored by vanadium substitution. Alloys with a suitable V substitution provide an excellent magnetocaloric effect with minor hysteresis in low magnetic fields up to 1.2 T. Mössbauer measurements show that the hyperfine field is reduced by V substitution. Neutron...

Combined effect of annealing temperature and vanadium substitution for mangetocaloric Mn_1.2-xV_xFe_0.75P_0.5Si_0.5 alloys

Approaching the border of the first order transition and second order transition is significant to optimize the giant magnetocaloric materials performance. The influence of vanadium substitution in the Mn_1.2-xV_xFe_0.75P_0.5Si_0.5 alloys is investigated for annealing temperatures of 1323,...

Reversible low-field magnetocaloric effect in Ni-Mn-In-based Heusler alloys

Ni-Mn-X (X = In, Sn, and Sb) based Heusler alloys show a strong potential for magnetic refrigeration owing to their large magnetocaloric effect (MCE) associated with first-order magnetostructural transition. However, the irreversibility of the MCE under low field change of 0–1 T directly hinders its application as an efficient magnetic coolant....

Positive muon spin rotation and relaxation measurements on the ferromagnetic superconductor UGe2 at ambient and high pressure

Results of a detailed investigation of the ferromagnetic superconductor UGe2 using positive muon spin rotation and relaxation techniques are presented. The pressure and temperature dependences of the frequencies and related spin-spin relaxation rates show that the transition from the weakly to the strongly polarized magnetic (WP-SP) phases is...