Study of the martensitic transition in Ni-Nn-Sn-Ti ferromagnetic shape memory alloys

F. G. BONIFACICH; O. A. LAMBRI; J. I. PÉREZ-LANDAZÁBAL; V. RECARTE; D. GARGICEVICH; G. I. ZELADA; R. R. MOCELLINI; V. SÁNCHEZ-ALARCOS; A. MARENZANA; F. PLAZAOLA

Córdoba

Congreso; Congreso SAM-CONAMET-IBEROMAT 2016; 2016

Ferromagnetic shape memory alloys (FSMA) are a potential actuator material that exhibit large strain and high frequency response. FSMA pilot samples are usually small and brittle. In the present work, a novel piezoelectric device for measuring mechanical spectroscopy (MS) as a function of temperature and strain has been developed in order to study Ni50Mn37Sn11-xTix (x=0, 2) FSMA. Differential thermal analysis (DTA) and Superconducting Quantum Interference Device (SQUID) measurements were also carried out. The equipment involves five oscillating elements, a crystal driver, two spacer bars, the sample and the crystal gauge [1]. The new device here developed results an important solution for measuring mechanical spectroscopy, where the condition of match in frequency cannot be satisfied due to limitations in the production process.Polycrystalline ingots of Ni50Mn37Sn13 and Ni50Mn37Sn11Ti2 (at.%) were prepared from high-purity elements by arc melting under a protective Ar atmosphere. The ingots were re-melted several times and then homogenized in vacuum quartz ampoules at 1273 K for 4 h.