Strains induced by magnetic field and phase transformation in Ni50.5Mn26.2Ga23.4 ferromagnetic shape memory alloy

In recent years, a lot of investigations have been focused on ferromagnetic shape memory alloys (FSMAS), such as Ni2MnGa, FePd, CoNi and FeNiCoTi [1–4], due to their large magnetic-field induced strain (MFIS) and high response frequency. Of the above alloys Ni Mn Ga alloy is the only known Heusler alloy ex-hibiting thermal martensitic phase transformation. It is reported up to now that a maximum 6 % of MFIS has been obtained in Ni49.8Mn28.5Ga21.7 single crystal by applying a constant 2 MPa compression stress [5]. However, few results have been reported about the tem-perature dependence of MFIS in NiMnGa alloy. The purpose of the present paper is to measure the MFIS along the [110] direction of Ni50.5Mn26.2Ga23.4 single crystal at different temperatures. It is interesting to fin