In situ TEM study of phase transformations in nonstoichiometric geisler alloy Ni$_{46}$Mn$_{41}$In$_{13}$

This paper presents a study of the metamagnetostructural transition of the martensitic type in the Ni$_{46}$Mn$_{41}$In$_{13}$ alloy with magnetic shape memory and inverse magnetocaloric effect. The characteristic temperatures of the direct transition starting $M_s$ = 253 K and its finishing $M_f$ = 164 K, as well as the reverse temperatures $A_s$ = 203 K and $A_f$ = 236 K, respectively, were determined by differential scanning calorimetry. The characteristic peculiarities of the transition: a decrease of the $M_s$ and the presence of a residual austenite phase, as well as pre-martensitic states, were studied using transmission electron microscopy. The estimated the thickness of alloy was 50 nm, when martensitic transition suppressed.