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The reversibility of the giant magnetocaloric effect (MCE) through the magnetic field–induced magnetostructural transformation in Ni–Mn–In‐based alloys is a key issue towards the potential magnetic refrigeration applications. In this work, Co and Cu are simultaneously doped to tune the reversible magnetocaloric properties associated with the magnetostructural transformation. Owing to the integration of large magnetization difference ΔM, suitable transformation entropy ΔStr, and narrow thermal hysteresis ΔThys in a Ni46Co3Mn35Cu2In14 alloy, the reversible field–induced inverse martensitic transformation is realized in a wide temperature range of 30 K under the field of 5T, yielding a maximum reversible magnetic entropy change ΔSMmax of 16.4 J kg−1 K−1. Moreover, under a low field change of 1.5T, a large reversible adiabatic temperature variation ΔTad of 2.5 K is also obtained, representing the highest value so far under the low field change of 1.5T in Ni–Mn‐based alloys. It is demonstrated that multi‐component alloying by combining the effects of appropriate substitutional elements is an effective way to develop high‐performance magnetocaloric materials.

We demonstrate the temperature dependent elastocaloric effect in a Ni44.9Co4.9Mn36.9In13.3 polycrystalline alloy with a strong ⟨001⟩A preferred orientation. It is found that the adiabatic temperature changes induced by the compressive stress increase with the increase in testing temperature. The giant adiabatic temperature change up to 14.7 K is achieved on loading at 390 K, which is much higher than that around room temperature. Such a temperature enhanced effect is attributed to the reduced magnetic contribution to the transformation entropy through narrowing the temperature interval between magnetic transition and martensitic transformation controlled by the mechanical stress.

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