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

ABSTRACT

In the present work, mechanical spectroscopy measurements as a function of temperature and strain have been performed in (at.%) Ni₅₀Mn₃₇Sn_13-xTi_x (x=0, 0.5 and 2) ferromagnetic shape memory alloys in order both to study martensitic transition phenomenon and also to determine its temperature of appearance. For mechanical spectroscopy measurements, a five elements piezoelectric device recently developed has been used. In addition, other characterization techniques as, differential thermal analysis and superconducting quantum interference magnetic spectroscopy, were also used. Besides, relaxation processes near the martensitic transition temperature have been also observed.

Keywords
NiMnSn; ferromagnetic shape memory alloys; composite piezoelectric oscillator; short and brittle samples