Stress-induced and thermoelastic properties of Ni-Fe-Al melt-spun ribbon

Abstract

Lattice parameters, elastic modulus, internal friction, superelasticity, and shape memory effect are studied in the vicinity of martensitic transformation (MT) exhibited by the Ni₅₅Fe₂₀Al₂₅ melt-spun ribbon. In comparison to the melt-spun ribbons of other ferromagnetic shape memory alloys, Ni-Fe-Al ribbon has abnormally low elastic modulus, a record-breaking strength (>350 MPa), and large recoverable strain (up to 5%) due to both the superelastic and ordinary shape memory effects. The critical stress versus temperature phase diagram consists of two straight lines, indicating the formation of different stress-induced martensitic phases. The structural and thermodynamic results proved to be self-consistent.