Study on martensitic transformation, magnetic and compressive properties of spray casting Ni-Mn-Ga alloys

Abstract

The influence of spray casting technique on martensitic transformation temperature, magnetic properties and compressive properties of Ni50Mn25+xGa25-x (x = 0, 1.25, 2.5, 3.75 and 5) alloys was investigated. With the increase in Mn content, martensitic transformation temperature of the spray casting samples is increased, but slightly lower than that of the corresponding as-cast ones. The saturation magnetization test shows the opposite tendency and proves the spray casting technique can effectively enhance the magnetic properties. Compression experiments showed that the spray casting process did not change the fracture strain, but lead to the greatly increase in the compressive strength and improve the brittleness of the Ni-Mn-Ga alloys. This study may offer a new processing technique for developing high performance ferromagnetic shape memory alloys.