Low temperature magnetic properties of a Ni50Mn34In16 ball-milled metamagnetic shape memory alloy

[EN] The effect of the atomic disorder induced by ball-milling on the structure and the magnetic properties has been analyzed in a Ni50Mn34In16 metamagnetic shape memory alloy. The as-milled samples displayed an amorphous structure which crystallizes to a disordered B2 structure on annealing. On further annealing, several recovery processes leading to the austenitic L21 structure and the subsequent martensitic transformation are observed. As a result of the recovery processes, the magnetic order drastically varies concurrent with the long-range atomic order. In particular, the magnetism evolves from a frustrated magnetic state compatible with a canonical spin-glass, observed in the amorphous structure, to the well-developed ferromagnetic state.This work has been carried out with the financial support of the Spanish “Ministerio de Economía y Competitividad” and FEDER funding, projects no. MAT2012-37923 and MAT2015-65165-C2-R. I. Unzueta acknowledges financial support from the Basque Government Grant nos. IT-443-10 and PRE_2014_214