Near room-temperature magnetostructural transition and low field large magnetocaloric effect in (MnNiSi)0.66(Fe2Ge)0.34 system.

The strong coupling of the spin and lattice subsystem exactly across the room-temperature region is observed in (MnNiSi)0.66(Fe2Ge)0.34 alloy which leads to a substantial change in magnetocaloric parameters. Substitution of Fe2Ge (Ni2In-type hexagonal symmetry) compound helps to distort the low temperature ferromagnetic phase and stabilize the high temperature paramagnetic phase near the room-temperature region. A large value of isothermal magnetic entropy change (ΔSM) of -13.67 J/kg-K at 300 K and relative cooling power (RCP) of 169.5 J/kg is observed for the (MnNiSi)0.66(Fe2Ge)0.34 alloy for a low magnetic field change of 30 kOe. Near room-temperature MST temperature and obtained large value of isothermal magnetic entropy change with large relative cooling power make the investigated (MnNiSi)0.66(Fe2Ge)0.34 alloy suitable for room-temperature solid state cooling applications. [ABSTRACT FROM AUTHOR]