Martensitic Transformations of Ni–Mn–X Heusler Alloys with X = Ga, In and Sn
Martensitic transformations of rapidly quenched and less rapidly cooled Heusler alloys of type Ni–Mn–X with X = Ga, In and Sn are investigated by ab initio calculations. For the rapidly cooled alloys, we obtain the magnetocaloric properties near the magnetocaloric transition. For the less rapidly quenched alloys these magnetocaloric properties start to change considerably. This shows that none of the Heulser alloys is in thermal equilibrium. Instead, each alloy transforms during temper-annealing into a dual-phase composite alloy. The two phases are identified to be cubic Ni–Mn–X and tetragonal NiMn.
KeywordsMagnetocaloric effect Heusler alloys First order phase transitions Segregation
We acknowledge support by the DFG priority program 1599 “ferroic cooling”. Calculations were carried out on the magnitude supercomputer (DFG grant INST 20876/208-1) at the CCSS at University of Duisburg-Essen.
- 9.Kouvel JD, Hartelius CC (1912) J Appl Phys 32:1343Google Scholar
- 19.Aseguinoaza JR, Colub V, Saluk OY, Muntifering B, Knowlton WB, Müllner P, Barandiaran JM, Cernenko VA (2016) Acta Mater 111:163Google Scholar
- 27.Kainuma R, Geijima F, Sutou Y, Ohnuma I, Aoko K, Ishida K (2000) JIM 41:943Google Scholar