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The effect of hydrostatic pressure on the martensitic transformation and magnetocaloric properties of MnNi0.88GeV0.12 alloy is studied in detail. X‐ray diffraction at room temperature shows that the alloy has a single hexagonal Ni2In‐type structure. The phase transition temperature moves to the low‐temperature region with the increase in hydrostatic pressure. Under the external magnetic field of 15 kOe, the hydrostatic pressure driving rates dTM/dP and dTA/dP are 60.25 and 65.25 K GPa−1, respectively, which indicate that the applied pressure expands the working temperature range of magnetic refrigeration. A magnetic entropy change ΔS of −4.8 J kg−1 K−1 is obtained in the external magnetic field of 15 kOe under ambient pressure. The peak value of |ΔS| is increased to 5.6 J kg−1 K−1 under hydrostatic pressure, which is closely related to the structural change of the alloy. [ABSTRACT FROM AUTHOR]

The elastocaloric effect and magnetic performance of Ni50Mn31.5Ti18Cu0.5 shape memory alloy were studied. The analysis of magnetic transformation shows that the transformation temperature of the alloy is close to room temperature. A large unloading rate can make the alloy showing smaller hysteresis and lower plastic deformation, and improve the superplasticity of the alloy. With the increase in loading stress, the cooling effect of the alloy is better. When the loading stress is 600 MPa, the ΔT of the alloy reaches 9 K. The alloy has good cycle stability during 100 cycles. Hence, the refrigeration performance of Ni50Mn31.5Ti18Cu0.5 alloy can be compared with many Ni-Mn-based alloys, which indicates that it is a promising elastocaloric refrigeration material. [ABSTRACT FROM AUTHOR]