Shape memory effect in melt spun Fe-15Mn-5Si-9Cr-5Ni alloys

P.LA ROCA; J.A.MALARRÍA; P. OCHIN; A .DRUKER

Montpellier

Congreso; European congress and exhibitions on advanced material and processes (EUROMAT-2011)); 2011

At room temperature, Fe-15Mn-5Si-9Cr-5Ni alloys are normally austenitic and the application of a stress induces a reversible martensitic transformation causing a shape memory effect (SME). However, when the material is obtained by a melt spinning technique, the rapid solidification stabilizes a high temperature ferritic phase. The goals of this work were to find the appropriate heat treatment in order to recover the equilibrium austenitic phase, characterize the ribbon form of this material and evaluate its shape memory behavior. We found that annealing at 1050ºC for 60 min, under an argon protective atmosphere, followed by a water quenching stabilizes the austenite to room temperature. The yield stress, measured by tensile tests, is 200MPa, well below that of conventionally rolled sheet of the same alloy. This difference results from the ribbon material´s microstructure and texture. The results from the shape memory tests demonstrate that the ribbons are capable of recovering enough of their shape for certain applications.