Microstructural, phase transformation and magnetic properties of Ni–Mn–Ga alloy fabricated by spark plasma sintering

The microstructural, phase transformation and magnetic properties of Ni–Mn–Ga alloy fabricated using the spark plasma sintering method have been investigated. The results show that both the as-sintered and annealed sintered specimens exhibit typical martensitic transformation behaviours. The martensite of the sintered specimen after annealing exhibits a ferromagnetic nature. Moreover, study of the fracture surface indicates that the transgranular fracture contributes to the higher ductility of sintered Ni–Mn–Ga alloy. In addition, the transformation strain in sintered Ni–Mn–Ga alloy is studied for the first time.