Concurrent effect of improving pseudoelasticity and shape memory effect on the recovery stress of FeMnSi based SMA

To investigate the impact of various maximum recovery temperatures on the recovery stress and strain,the recently developed Fe-based shape memory alloy with various thermomechanical and heattreatment conditions was taken into consideration. Based on the competition of favorable grainrefinement, there is a trade-off between pseudoelasticity and the shape memory effect. It was found thatimproving PE sacrifices SME in grain refined specimens, and recovery stress tends to go up with PEimprovement. For As-received aged samples due the non-uniform distribution of precipitates, thestrained specimen tends to reverse back from austenite to martensite during cooling of stress recoverytests.

Keywords:

Shape memory alloys , Fe-Mn-Si , Pseudoelasticity , Stress recovery , Strain recovery