Abstract:
Since the discovery of the magnetic property of NiMnGa Heusler system, Ni-Mn-based Heusler alloys have attracted because of their capability on technological applications. For instance, they are tunable with their compositions, temperature, magnetic field, etc. These alloys could have martensitic and magnetic transformations around room temperature which makes them a strong candidate especially refrigeration technologies. We present the first-order martensitic transformation, magnetic, and structural properties in selected NiMnX11(X = In, Sn) Heusler alloys. These compositional tuning of the X element became more prominent in thermomagnetization measurements. While NiMnIn11 alloy has martensite start temperature, austenite finish temperature, and Curie temperature at 277, 289, and 310 K, respectively, these temperatures are at 300, 321, and 320 K for NiMnSn11 alloy. All of the martensitic transformations and Curie temperatures have obtained near room temperature. The XRD data of alloys were refined and gave typical structure properties of non-stoichiometric Ni-Mn Heusler as a mixture of L1(0) tetragonal martensite and L2(1)-type cubic austenite.
