The microstructure, martensitic transformation (MT) and shape memory effect (SME) of the dual-phase Ni58Mn25Ga17−xGdx (x = 0, 0.1, 0.2, 0.5, 1) alloys have been investigated. The results show that the refined the grain size and adjust the distribution of γ phase by added rare earth Gd in the Ni58Mn25Ga17−xGdx alloys. With increasing Gd content, the MT temperatures of Ni58Mn25Ga17−xGdx alloys first gradually decrease and then increase with the increasing content of Gd, reaching their minimum values when the content of Gd is 0.5 at.-%. In addition, the Ni58Mn25Ga16.9Gd0.1 has a SME of 5.1% owing to the favourable γ phase distribution, which is mainly attributable to the γ phase grain refined and weaken resistance of reverse MT.
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